UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-K

FOR ANNUAL AND TRANSITION REPORTS PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT

For the fiscal year ended December 31, 20032005

OR

For the transition period from                    to                    

Commission file number: 000-30110

SBA COMMUNICATIONS CORPORATION

(Exact name of Registrant as specified in its charter)

Registrant’s telephone number, including area code: (561) 995-7670

Securities registered pursuant to Section 12(b) of the Act:

NoneNONE

Securities registered pursuant to Section 12(g) of the Act:

Class A common stock, $.01 par value

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes  x No  ¨

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Exchange Act. Yes  ¨ No  x

Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yesx No¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of Registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.x¨

Indicate by check mark whether the Registrant is a large accelerated filer, an accelerated filer, or a non-accelerated filer. See definition of “accelerated filer and large accelerated filer” in Rule 12b-2 of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act Rule 12b-2).Act. Yesx  No¨

No  x

The aggregate market value of the voting stock held by non-affiliates of the Registrant was approximately $132.2$783.4 million as of June 30, 2003.

2005.

The number of shares outstanding of the Registrant’s common stock (as of March 10, 2004)6, 2006):

Class A common stock—56,017,207stock — 85,738,634 shares

Documents Incorporated By Reference

Portions of the Registrant’s definitive proxy statement for its 20042006 annual meeting of shareholders, which proxy statement will be filed no later than 120 days after the close of the Registrant’s fiscal year ended December 31, 2003,2005, are hereby incorporated by reference in Part III of this Annual Report on Form 10-K.

PART I

General

We are a leading independent owner and operator of over 3,000 wireless communications towerstowers. We currently operate in the easternEastern third of the United States. We generate revenues fromStates, where substantially all of our two primary businesses,towers are located. Our principal business line is our site leasing and site development.business. In our site leasing business, we lease antenna space to wireless service providers on towers and other structures that we own, or manage for or lease from others. The towers that we own have been constructed by us at the request of a carrier,wireless service provider, built or constructed based on our own initiative or acquired. We have built approximately 60% of our currently owned towers. As of December 31, 2003,2005, we owned 3,0933,304 towers of which 3,032 are in continuing operations. InOur second business line is our site development business, through which we offer wireless service providers assistance in developing and maintaining their own wireless service networks. Since our founding in 1989, we have participated in the development of more than 25,000 antenna sites in 49 of the 51 major wireless markets in the United States.

Site Leasing Services

Our primary focus is the leasing of antenna space on our multi-tenant towers to a variety of wireless service providers under long-term lease contracts. We believe that over the long term our site leasing revenues will continue to grow as wireless service providers lease additional antenna space on our towers due to increasing minutes of use and network coverage requirements. We lease antenna space on the towers we have constructed, the towers we have acquired, and the towers we lease, sublease and/or manage for third parties. Our site leasing revenue comes from a variety of wireless carrierservice provider tenants, including AT&T Wireless,Alltel, Cingular, Wireless,Sprint Nextel, Sprint PCS, T-Mobile and Verizon Wireless, and weWireless. We believe our current tower portfolio positions us to take advantage of wireless carriers’service providers’ antenna and equipment deployment.

As of December 31, 2005, we owned 3,304 towers, up from 3,060 as of December 31, 2004. We currently believe that tower portfolio growth is the best use of our capital resources to provide our shareholders long-term value. Consequently, we are currently pursuing a limited new build program and tower acquisition program. Pursuant to these new initiatives, we built 36 towers and acquired 208 towers during 2005. The towers under our new build program will be constructed either (1) under build-to-suit arrangements or (2) in locations chosen by us. Under our build-to-suit arrangements, we build towers for wireless service providers at locations that they have identified. We retain ownership of the tower and the exclusive right to co-locate additional tenants on the tower. In addition, we intend on building towers on locations chosen by us. Based on our knowledge of our customers’ needs, we seek to identify attractive locations for new towers and complete pre-construction procedures necessary to secure the site leasing business is characterized by stable and long-term recurring revenues, predictable operating costs and minimal capital expenditures. We expect to grow our cash flows by adding tenants to our towers at minimal incremental costs by using existing tower capacity or requiring carriers to bear the cost of tower modifications. Because our towers are strategically positioned and our customers typically do not re-locate, we have historically experienced low customer churn as a percentage of revenue. Our lease contracts typically have terms of five years or moreconcurrently with multiple term tenant renewal options and provide for annual rent escalators. We are focusing our leasing activities in the eastern third of the United States whereefforts. Our intent is that substantially all of our new builds will have at least one signed tenant lease on the day that it is completed and we expect that some will have multiple tenants. We currently intend to build 80 to 100 new towers are located. Additionally, dueduring 2006. With respect to acquisitions, we intend to pursue towers that meet or exceed our internal guidelines regarding current and future potential returns and the relatively young ageimpact of such acquisition on our leverage ratios. For each acquisition, we prepare various analyses that include (1) projections of a five-year internal rate of return, (2) review of available capacity for future lease up projections, and mix(3) summary of current and future tenant/technology mix.

The table below provides information regarding the development and status of our tower portfolio we expect future expenditures required to maintain these towers will be low.over the past five years.

The following chart shows the number of towers we built for our own account, the number of towers we acquired, the number of towers we reclassified or disposed of, the number of towers held for sale and the number of towers owned for the periods indicated, before discontinued operations treatment:

through licensed contractors, who may be our employees or independent contractors. Local regulations include city and other local ordinances, zoning restrictions and restrictive covenants imposed by community developers. These regulations vary greatly from jurisdiction to jurisdiction, but typically require tower and structure owners to obtain approval from local officials or community standards organizations, or certain other entities prior to tower or structure construction and establish regulations regarding maintenance and removal of towers or structures. In addition, many local zoning authorities require tower and structure owners to post bonds or cash collateral to secure their removal obligations. Local zoning authorities generally have been unreceptive to construction of new antenna towers and structures in their communities because of the height and visibility of the towers or structures, and have, in some instances, instituted moratoria.

Backlog

Our backlogBacklog related to our site leasing business consists of pending leases for antenna space on our towers varies from time to timelease agreements and reflects the relatively short-cycle of three to six months of the antenna space leasing process. Leasing backlogs vary widely within a fiscal quarter, and are generally lowest on the last day of a quarter as our customers strive to meet their own quarterly antenna site deployment goals.amendments, which have been signed but have not yet commenced. As of December 31, 20032005, we had136 122 new leases which had been executed with customers but which had not begun generating revenue. These leases contractually provided for approximately $2.6 million of annual revenue. By comparison, at December 31, 2004 we had 113 new leases and 154 amendments which had been executed with customers but which had not begun generating revenue. These leases contractually provided for approximately $2.8$2.5 million of annual revenues. As of December 31, 2002 we had150 new leases and 9 amendments which had been executed with customers but which had not begun generating revenue. These leases contractually provided for approximately $3.3 million of annual revenues.

Our backlog for site development services was approximately $80$48 million of contractually committed revenue as of December 31, 2005 as compared to approximately $62 million as of December 31, 2003 as compared to approximately $29 million as of December 31, 2002.2004. The increasedecrease in 20032005 is attributable to a 2003 contract received fromsigned with Sprint for site development work whichthat is expected to result in revenues of $70be completed by mid 2007. This contract represented approximately $26 million to $90 million over a two year period of which approximately $60 million is reflected in backlog as of December 31, 2003. We had no2005 and approximately $46 million in backlog for pending tower acquisitions as of December 31, 2003.2004.

Availability of Reports and Other Information

Our corporate website is www.sbasite.com. We make available, free of charge, access to our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, Proxy Statement on Schedule 14A and amendments to those materials filed or furnished pursuant to Section 13(a) or 15(d) of the Securities and Exchange Act of 1934 on our website under “Investor Relations - SEC Filings,” as soon as reasonably practicable after we file electronically such material with, or furnish it to, the United States Securities and Exchange Commission (the “Commission”). In addition, the Commission’s website is www.sec.gov. The Commission makes available on this website, free of charge, reports, proxy and information statements, and other information regarding issuers, such as us, that file electronically with the Commission. Additionally, our reports, proxy and information statements may be read and copied at the Commission’s public reference room at 100 F Street, NE, Washington, DC 20549. Information on our website or the Commission’s website is not part of this document.

Risks Related to Our Business

We may not be able to service our substantial indebtedness.

As indicated below, we have and will continue to have a significant amount of indebtedness relative to our equity.

Our ability to service our debt obligations will depend on our future operating performance. Our earnings were insufficient to cover our fixed charges for the year ended December 31, 2003 by $162 million and $184 million for the year ended December 31, 2002. Subsequent to December 31, 2003 we obtained a new senior credit facility. A portion of the proceeds from this facility were used to repay the then existing credit facility, to purchase 12% senior discount notes in the open market, to redeem all 12% senior discount notes outstanding on March 1, 2004, and to repurchase 10¼% senior notes in the open market. As adjusted for these transactions, we would require approximately $53.5 million of cash flow from operating activities (before net cash interest expenses) to discharge our cash interest and principal obligations for the year ending December 31, 2004. By comparison, for the year ended December 31, 2003, we generated $56.7 million of cash flow from operations (before net cash interest expenses). In order to manage our substantial amount of indebtedness, we may from time to time sell assets, issue equity, or

repurchase, restructure or refinance some or all of our debt.debt (all of which we have done at various times in the last two years). We may not be able to effectuate any of these alternative strategies on satisfactory terms in the future, if at all. The implementation of any of these alternative strategies may dilute our current shareholders or subject us to additional costs or restrictions on our ability to manage our business and as a result could have a material adverse effect on our financial condition and growth strategy.

We may not have sufficient liquidity or cash flow from operations to repay the remaining amount of our outstanding senior credit facility, our 10¼% senior notes and our 9¾9 ³/4% senior discount notes or our 8 ¹/2% senior notes upon their respective maturities in 2008, 2009 and 2011.maturities. Therefore, prior to the maturity of our outstanding debt

notes we may be required to refinance and/or restructure some or all of this debt. There can be no assuranceWe cannot assure you that we will be able to refinance or restructure this debt on acceptable terms or at all.all, and, in particular, we cannot assure you that interest rates will be favorable to us at the time of any such refinancing or restructuring. If we were unable to refinance, restructure or otherwise repay the principal amount of this debt upon its maturity, we may need to sell assets, cease operations and/or file for protection under the bankruptcy laws.

We may not have sufficient liquidity or cash flow from operations to repay the components of the mortgage loan that comprises part of the CMBS Transaction. Therefore, prior to the final repayment date for the components of the mortgage loan we may be required to refinance the mortgage loan or sell a portion or all of our interests in the 1,714 tower sites that. among other things, secure along with their operating cash flows the mortgage loan. Although, the mortgage loan is a limited recourse obligation of SBA Properties, Inc. and no holder of the mortgage loan will have recourse to SBA Communications, our operations would be adversely affected if SBA Properties is unable to repay the components of the mortgage loan. We cannot assure you that our assets would be sufficient to repay this indebtedness in full.

As of December 31, 2003, adjusted for the transactions discussed above,2005, we would have had approximately $21 million of additional borrowing capacityno borrowings under our $160.0 million senior credit facility of which $39.1 million was available (giving effect to leverage limitations contained in the indenture governing the 9 ³/4% senior discount notes) subject to maintenance covenants, borrowing base limitations and other conditions. Furthermore, we and our subsidiaries may be able to incur significant additional indebtedness in the future, subject to the restrictions contained in our debt instruments, some of which may be secured debt.

We are dependentmay not secure as many site leasing tenants as planned or our lease rates for new tenant leases may decline.

If tenant demand for tower space or our lease rates for new tenant leases decrease, we may not be able to successfully grow our site leasing business. This may have a material adverse effect on our strategy, revenue growth and our ability to satisfy our financial and other contractual obligations. Our plan for the financial stabilitygrowth of our site leasing business largely depends on our management’s expectations and assumptions concerning future tenant demand and potential lease rates for independently owned towers.

If our wireless service provider customers combine their operations to a significant degree, our growth, our revenue and any deterioration in their financial condition may reduce the demandour ability to service our indebtedness could be adversely affected.

Demand for our services may decline if there is significant consolidation among our wireless service provider customers as they may then reduce capital expenditures in the aggregate because many of their existing networks and expansion plans overlap. As a result of regulatory changes in January 2003 which removed prior restrictions on wireless service providers from owning more than 45 MHz of spectrum in any given geographical area, there have been significant consolidations of the large wireless service providers. Specifically, Cingular acquired AT&T Wireless in October 2004 and Sprint PCS and Nextel merged to form Sprint Nextel Corporation in August 2005. To the extent that our customers have consolidated or that other customers may consolidate in the future, they may not renew any duplicative leases that they have on our towers and/or may not lease as much space on our towers in the future. This would adversely affect our growth, strategy, revenuesour revenue and financial condition.

Our business depends on the financial stability of our customers. The economic slowdown and intense competition in the wireless and telecommunications industries over the past several years have impaired the financial condition of some of our customers, certain of which operate with substantial leverage and certain of which have filed or may file for bankruptcy. The financial uncertainties facing our customers could reduce demand for our communications sites, increase our bad debt expense and reduce prices on new customer contracts. This could affect our ability to satisfyservice our obligations.indebtedness.

As of December 31, 2005, Cingular and the former AT&T Wireless both had leases on 274 of our 3,304 towers. The contractual revenue generated by these leases on these towers at December 31, 2005 was approximately $13.6 million. Consequently, if Cingular were not to renew duplicate leases, we could lose 50% or more of such revenue. As of December 31, 2005, the average remaining contractual life of such duplicate leases was approximately 2.9 years. Our risk of revenue loss from the integration of Cingular and AT&T is not limited to leases on the same tower. We expect Cingular to terminate or not renew some leases on our towers where they have other antenna sites in close proximity. Such terminations or non-renewals could have a material adverse impact on our growth rate.

In addition,As of December 31, 2005, Sprint Nextel and affiliated entities had multiple leases on 421 of our 3,304 towers. The contractual revenue generated by these leases on these towers at December 31, 2005 was approximately $19.7 million. Consequently, if Sprint Nextel were not to renew duplicate leases, we could lose 50% or more of such revenue. As of December 31, 2005, the average remaining contractual life of such duplicate leases was approximately 3.5 years. Our risk of revenue loss from the integration of Sprint Nextel merger is not limited to leases on the same tower. We expect Sprint Nextel to terminate or not renew some leases on our towers where they have other antenna sites in close proximity. Such terminations or non-renewals could have a material adverse impact on our growth rate.

Similar consequences may be negatively impacted by our customers’ limited access to debt and equity capital. Recently when capital market conditions were difficult for the telecommunications industry,occur if wireless service providers conserved capitalengage in extensive sharing or roaming or resale arrangements as an alternative to leasing our antenna space. Wireless voice service providers frequently enter into roaming agreements with competitors allowing them to use another’s wireless communications facilities to accommodate customers who are out of range of their home provider’s services. Wireless voice service providers may view these roaming agreements as a superior alternative to leasing antenna space on communications sites owned or controlled by not spending as much as originally anticipated to finance expansion activities. This decrease adversely impacted demandus or others. The proliferation of these roaming agreements could have a material adverse effect on our revenue.

We depend on a relatively small number of customers for most of our services and consequentlyrevenue.

We derive a significant portion of our financial condition. Asrevenue from a result, we adjusted our business during 2002 and early 2003 to significantly reduce and subsequently suspend any material investment for new towers andsmall number of customers, particularly in our site development activities. Ifservices business. The loss of any significant customer could have a material adverse effect on our revenue.

The following is a list of significant customers are not able to accessand the capital markets inpercentage of our total revenues for the future, our growth strategy, revenues and financial condition may again be adversely affected.specified time periods derived from these customers:

We also have client concentrations with respect to revenues in each of our financial reporting segments:

Revenues from these clients are derived from numerous different site leasing contracts and site development contracts. Each site leasing contract relates to the lease of space at an individual tower site and is generally for an initial term of five years renewable for five five-year periods at the option of the tenant. Our site development customers engage us on a project-by-project basis, and a customer can generally terminate an assignment at any time without penalty. In addition, a customer’s need for site development services can decrease, and we may not be successful in establishing relationships with new customers. Furthermore, our existing customers may not continue to engage us for additional projects.

Our substantial indebtedness may negatively impact our ability to implement our business plan.

Our substantial indebtedness may negatively impact our ability to implement our business plan. For example, it could:

Risks associated with our plans to increase our tower portfolio could negatively impact our results of operations or our financial condition.

We currently intend to increase our tower portfolio through new builds and acquisitions. We intend to review all available acquisition opportunities (including some that are currently available) and some of these acquisitions could have the effect of materially increasing our tower portfolio. While we intend to fund a portion of the cash required to implement this plan from our cash flow from operating activities, we may finance some or all of the costs associated with these new builds and acquisitions. Furthermore, if we were to consummate any significant acquisition, we would be required to finance these acquisitions through additional indebtedness, which would increase our indebtedness and interest expense and could increase our leverage ratio, and/or issuances of equity, which could be dilutive to our shareholders. If we were unable to recognize the expected returns from these new towers, or if we did not recognize the expected returns in our anticipated time frames, the increase in debt levels without a proportionate increase in our revenues could negatively impact our results of operations and our financial condition.

Due to the long-term expectation of revenue from our tenant leases, we are dependent on the financial strength and creditworthiness of our customers.

Due to the long-term nature of our tenant leases, we, like others in the tower industry, are dependent on the continued financial strength of our tenants. The economic slowdown and intense competition in the wireless and telecommunications industries in 2001 through 2003 had impaired the financial condition of some of our customers, certain of which operate with substantial leverage. As a result, a number of our site leasing customers have filed for bankruptcy including almost all of our paging customers. Although these bankruptcies have not had a material adverse effect on our business or revenues, any future bankruptcies may have a material adverse effect on our business, revenues, and/or the collectability of our accounts receivable. In the future, the financial uncertainties facing our customers could reduce demand for our communications sites, increase our bad debt expense and reduce prices on new customer contracts. This could affect our ability to satisfy our obligations.

In addition, our anticipated growth could be negatively impacted if our customers’ access to debt and equity capital were limited. From 2001 through 2003, when capital market conditions were difficult for the telecommunications industry, wireless service providers conserved capital by not spending as much as originally anticipated to finance expansion activities. This decrease adversely impacted demand for our services and consequently our financial condition. If our customers are not able to access the capital markets in the future, our growth strategy, revenues and financial condition may again be adversely affected.

Our debt instruments contain restrictive covenants that could adversely affect our business.

Our senior credit facility and the indentures governing our outstanding notes each contain certain restrictive covenants. Among other things, these covenants restrictlimit our ability to:

If we fail to comply with these covenants, it could result in an event of default under one or all of these debt instruments. The acceleration of amounts due under one of our debt instruments would also cause a cross-default under our other debt instruments.

SBA Senior Finance Inc.II LLC (“SBA Senior Finance”Finance II”), which owns, directly or indirectly, all of the common stock and membership interests of the majority of our operating subsidiaries, is the borrower under our senior credit facility. The senior credit facility requires SBA Senior Finance II to maintain specified financial ratios, including ratios regarding SBA Senior Finance’sFinance II’s debt to annualized operating cash flow, debt service, cash interest expense and fixed charges for each quarter. In addition, the senior credit facility contains additional negative covenants that, among other things, restrictlimit our ability to commit to capital expenditures and build or acquire towers without anchor or acceptable tenants. Our ability to meet these financial ratios and tests and comply with these covenants can be affected by events beyond our control, and we may not be able to do so. A breach of any of these covenants, if not remedied within the specified period, could result in an event of default under the senior credit facility.

Upon the occurrence of any default, our senior credit facility lenders can prevent us from borrowing any additional amounts under the senior credit facility. In addition, upon the occurrence of any event of default, other than certain bankruptcy events, senior credit facility lenders, by a majority vote, can elect to declare all amounts of principal outstanding under the senior credit facility, together with all accrued interest, to be immediately due and payable. The acceleration of amounts due under our senior credit facility would cause a cross-default under our indentures, thereby permitting the acceleration of such indebtedness. If the indebtedness under the senior credit facility and/or indebtedness under our outstanding notes were to be accelerated, our current assets would not be sufficient to repay in full the indebtedness. If we were unable to repay amounts that become due under the senior credit facility, the senior credit facility lenders could proceed against the collateral granted to them to secure that indebtedness. Substantially all of our assets are pledged as securityAmounts borrowed under the senior credit facility.facility are secured by a first lien on substantially all of Senior Finance II’s assets and are guaranteed by SBA Communications and certain of its subsidiaries. In such an event of default, our assets may not be sufficient to satisfy our obligations under the notes.

Our $405.0 million mortgage loan relating to our CMBS Certificates contains a covenant requiring all cash flow in excess of amounts required to make debt service payments, to fund required reserves, to pay management fees and budgeted operating expenses and to make other payments required under the loan documents be deposited into a reserve account if the debt service coverage ratio falls to 1.30 times or lower, as of the end of any calendar quarter. Debt service coverage ratio is defined as the Net Cash Flow (as defined in the mortgage loan) divided by the amount of interest on the mortgage loan, servicing fees and trustee fees that SBA Properties, Inc. will be required to pay over the succeeding twelve months. If our wirelessthe debt service provider customers combine their operationscoverage ratio falls below 1.15 times as of the end of any calendar quarter, then an “amortization period” will commence and all funds on deposit in the reserve account will be applied to a significant degree, our growth, our revenue andprepay the mortgage loan. The funds in the reserve account will not be released to SBA Properties unless the debt service coverage ratio exceeds 1.30 times for two consecutive calendar quarters. Failure to maintain the debt service coverage ratio above 1.30 times would impact our ability to generate positivepay our indebtedness other than the mortgage loan and to operate our business.

The mortgage loan provides for customary remedies if an event of default occurs including foreclosure against all or part of the property pledged as security for the mortgage loan. The mortgage loan is secured by (1) mortgages, deeds of trust and deeds to secure debt on substantially all of the 1,714 collateralized tower sites and their operating cash flow could be adversely affected.

Demand for our services may decline if there is significant consolidation among our wireless service provider customers as they may then reduce capital expendituresflows, (2) a security interest in substantially all of SBA Properties’ personal property and fixtures and (3) SBA Properties’ rights under the aggregate because manymanagement agreement with SBA Network Management, Inc. (who manages all of their existing networks and expansion plans overlap. In January 2003, the spectrum cap, which previously prohibited wireless carriers from owning more than 45 MHz of spectrum in any given geographical area, expired. Some wireless carriers may be encouraged to consolidate with each other as a result of this regulatory change and as a means to strengthen their financial condition. Economic conditions have resulted in the consolidation of several wireless service providers and this trend is likely to continue. To the

extentSBA Properties’ sites). We cannot assure you that our customers consolidate, they may not renew any duplicative leases that they have on our towers and/or may not lease as many spaces on our towersassets would be sufficient to repay this indebtedness in the future. This would adversely affect our growth, our revenue and our ability to generate positive cash flow. In February 2004, Cingular Wireless and AT&T Wireless entered into an agreement by which Cingular would acquire AT&T in a transaction anticipated to close in late 2004 or 2005. As of December 31, 2003 Cingular and AT&T were both tenants on 287 of our 3,032 towers. The contractual revenue generated by both of these tenants on these 287 towers at December 31, 2003 was approximately $12 million. If, as a result of this transaction, Cingular were not to renew duplicate leases, we could lose up to 50% of such revenue. The average remaining contractual life of such duplicate leases was approximately 3 years.

Similar consequences may occur if wireless service providers engage in extensive sharing or roaming or resale arrangements as an alternative to leasing our antenna space. Wireless voice service providers frequently enter into roaming agreements with competitors allowing them to use another’s wireless communications facilities to accommodate customers who are out of range of their home provider’s services. Wireless voice service providers may view these roaming agreements as a superior alternative to leasing antenna space on communications sites owned or controlled by us or others. The proliferation of these roaming agreements could have a material adverse effect on our revenue.

We depend on a relatively small number of customers for most of our revenue.

We derive a significant portion of our revenue from a small number of customers, particularly in our site development services business. The loss of any significant customer could have a material adverse effect on our revenue.

The following is a list of significant customers and the percentage of our total revenues for the specified time periods derived from these customers:

We also have client concentrations with respect to revenues in each of our financial reporting segments:

Revenues from these clients are derived from numerous different site leasing contracts and site development contracts. Each site leasing contract relates to the lease of space at an individual tower site and is generally for an initial term of five years renewable for five five-year periods at the option of the tenant. Our site development customers engage us on a project-by-project basis, and a customer can generally terminate an assignment at any time without penalty. In addition, a customer’s need for site development services can decrease, and we may not be successful in establishing relationships with new customers. Furthermore, our existing customers may not continue to engage us for additional projects.

We may not secure as many site leasing tenants as planned or our lease rates may decline.

If tenant demand for tower space or our lease rates for new tenants decrease, we may not be able to successfully grow our site leasing business. This may have a material adverse effect on our strategy, revenue growth and our ability to satisfy our financial and other contractual obligations. Our plan for the growth of our site leasing business largely depends on our management’s expectations and assumptions concerning future tenant demand and potential lease rates for independently owned towers.

Due to the long-term expectations of revenue from our tenant leases, we are very sensitive to the creditworthiness of our tenants.

Due to the long-term nature of our tenant leases, we, like others in the tower industry, are dependent on the continued financial strength of our tenants. Wireless service providers often operate with substantial leverage, and financial problems for our customers could result in uncollected accounts receivable, the loss of customers and lower than anticipated lease revenues. During the past three years, a number of our site leasing customers have filed for bankruptcy including almost all of our paging customers. Although these bankruptcies have not had a material adverse effect on our business or revenues, any future bankruptcies may have a material adverse effect on our business, revenues, and/or the collectability of our accounts receivable.

full.

Our quarterly operating results for our site development services fluctuate and therefore should not be considered indicative of our long-term results.

The demand for our site development services fluctuates from quarter to quarter and should not be considered as indicative of long-term results. Numerous factors cause these fluctuations, including:

Although the demand for our site development services fluctuates, we incur significant fixed costs, such as maintaining a staff and office space in anticipation of future contracts. In addition, the timing of revenues is difficult to forecast because our sales cycle may be relatively long. Therefore, we may not be able to adjust our cost structure in a timely basis to adjust toaccommodate market slowdowns.

We are not profitable and expect to continue to incur losses.

We are not profitable. The following chart shows the net losses we incurred for the periods indicated:

Our losses are principally due to significant interest expense and depreciation and amortization in each of the periods presented above. WeFor the year ended December 31, 2005, we recorded an asset impairment chargecharges of $17.0$0.4 million and a charge associated with the write-off of deferred financing fees and loss on the extinguishment of debt of $29.3 million. For the year ended December 31, 2004, we recorded an asset impairment charge of $7.1 million and a charge associated with the write-off of deferred financing fees and loss on the extinguishment of debt of $41.2 million. We recorded an asset impairment charge of $13.0 million, a charge associated with the loss from write-off of deferred financing fees and extinguishment of debt of $24.2 million, and a restructuring charge of $2.5$2.1 million during the year ended December 31, 2003. Additionally, we recognized a loss, net of taxes, of approximately $7.7 million for the year ended December 31, 2003 in connection with discontinued operations. We recorded restructuring and other charges of $47.8 million, a $60.7 million charge related to the cumulative effect of a change in accounting principle related to the adoption of SFAS No. 142, and an asset impairment charge of $25.5 million in the year ended December 31, 2002. We recorded restructuring and other charges of $24.4 million in the year ended December 31, 2001.

In 2004, we expect to incur material additional charges for the write-off of deferred financing fees and extinguishment of debt associated with the senior credit facility refinancing, 10¼% senior note repurchases and 12% senior discount note repurchases and redemptions which occurred subsequent to December 31, 2003. Interest expense and depreciation charges will continue to be substantial in the future.

incur significant losses which may affect our ability to service our indebtedness.

Increasing competition in the tower industry may adversely affect us.

Our industry is highly competitive, particularly with respect to securing quality tower assets and adequate capital to support tower networks.competitive. Competitive pressures for tenants on their towers from theseour competitors could adversely affect our lease rates and services income. In addition, the loss of existing customers or the failure to attract new customers would lead to an accompanying adverse effect on our revenues, margins and financial condition. Increasing competition could also make the acquisition of quality tower assets more costly.costly, which could adversely affect our ability to successfully implement and/or maintain our tower acquisition program.

WeIn the site leasing business, we compete with:

Wireless service providers that own and operate their own tower networks and several of the other tower companies generally are substantially larger and have greater financial resources than we do. We believe that tower location and capacity, quality of service, density within a geographic market and, to a lesser extent, price historically have been and will continue to be the most significant competitive factors affecting the site leasing business.

The site development market includes participants from a varietyservices segment of market segments offering individual,our industry is also extremely competitive. There are numerous large and small companies that offer one or combinationsmore of competing services. We believe that a company’s experience, track record, local reputation, price and time for completion of a project have been and will continue to be the most significant competitive factors affecting theservices offered by our site development business. As a result of this competition, margins in this segment have decreased over the past few years. Many of our competitors have lower overhead expenses and therefore may be able to provide services at prices that we

consider unprofitable. If margins in this segment were to further decrease, our consolidated revenues and our site development segment operating profit could be adversely affected.

We may not be able to build and/or acquire as many towers as we anticipate.

We currently intend to build 80 to 100 new towers during 2006 and to consummate a number of tower acquisitions. However, our ability to build these new towers is dependent upon the availability of sufficient capital to fund construction, our ability to locate, and acquire at commercially reasonable prices, attractive locations for such towers and our ability to obtain the necessary zoning and permits.

Our ability to consummate tower acquisitions is also subject to risks. Specifically, these risks include (1) sufficient capital to fund such acquisitions, (2) our ability to identify those towers that would be attractive to our clients and accretive to our financial results, and (3) our ability to negotiate and consummate agreements to acquire such towers. Due to these risks, it may take longer to complete our new tower builds than anticipated, the costs of constructing or acquiring these towers may be higher than we expect or we may not be able to add as many towers as we had planned in 2006. If we are not able to increase our tower portfolio as anticipated, it could negatively impact our ability to achieve our financial goals.

The loss of the services of certain of our key personnel or a significant number of our employees may negatively affect our business.

Our success depends to a significant extent upon performance and active participation of our key personnel. We cannot guarantee that we will be successful in retaining the services of these key personnel. We have employment agreements with Jeffrey A. Stoops, our President and Chief Executive Officer, Kurt L. Bagwell, our Senior Vice President and Chief Operating Officer, and Thomas P. Hunt, our Senior Vice President and General Counsel. We do not have employment agreements with any of our other key personnel. If we were to lose any key personnel, we may not be able to find an appropriate replacement on a timely basis and our results of operations could be negatively affected. We do not currently have a permanent Chief Financial Officer, and if we are unable to timely hire one, our business may be negatively impacted. Further, the loss of a significant number of employees or our inability to hire a sufficient number of qualified employees could have a material adverse effect on our business.

New technologies and their use by carrierswireless service providers may have a material adverse effect on our growth rate and results of operations.

The emergence of new technologies could reduce the demand for space on our towers. For example, the developmentincreased use by wireless service providers of signal combining and related technologies and products that allow two or more wireless service providers to provide services on different transmission frequencies using the communications antenna and other facilities normally used by only one wireless service provider could reduce the demand for our tower space. Additionally, the use of productstechnologies that would permit multiple wireless carriers to use a single antenna, share networksenhance spectral capacity, such as beam forming or “smart antennae,” that can increase the range and capacity of an antenna could reduce the number of antennas neededadditional sites a wireless service provider needs to adequately serve a certain subscriber base and therefore reduce demand for our tower space. The development and growth of communications and other new technologies that do not require ground-based sites, such as the growth in delivery of video, voice and data services by satellites or other technologies, could also adversely affect the demand for our customers.tower space. In addition, the deployment of WiFi and WiMax technologies could impact the network needs of our existing customers providing wireless telephony services. This could have a material adverse effect on our growth rate and results of operations.

Delays or changes in the deployment or adoption of new technologies as well as lower consumer demand and slower consumer adoption rates than anticipated may have a material adverse effect on our growth rate.

There can be no assurances that 3G or other new wireless technologies will be deployed or adopted as rapidly as projected or that these new technologies will be implemented in the manner anticipated. The deployment of 3G has already experienced significant delays from the original projected timelines of the wireless and broadcast industries. Additionally, the demand by consumers and the adoption rate of consumers for these new technologies once deployed may be lower or slower than anticipated. These factors could have a material

adverse effect on our growth rate since growth opportunities and demand for our tower space as a result of such new technologies may not be realized at the times or to the extent anticipated.

Our costs could increase and our revenues could decrease due to perceived health risks from radio frequency (“RF”) energy.

The government imposes requirements and other guidelines on our towers relating to RF energy. Exposure to high levels of RF energy can cause negative health effects.

The potential connection between exposure to low levels of RF energy and certain negative health effects, including some forms of cancer, has been the subject of substantial study by the scientific community in recent years. According to the Federal Communications Commission (“FCC”),FCC, the results of these studies to date have been inconclusive. However, public perception of possible health risks associated with cellular and other wireless communications media could slow the growth of wireless companies, which could in turn slow our growth. In particular, negative public perception of, and regulations regarding, health risks could cause a decrease in the demand for wireless communications services. Moreover, if a connection between exposure to low levels of RF energy and possible negative health effects, including cancer, were demonstrated, we could be subject to numerous claims. If we were subject to claims relating to RF energy, even if such claims were not ultimately found to have merit, our financial condition wouldcould be materially and adversely affected.

Our business is subject to government regulations and changes in current or future regulations could harm our business.

We are subject to federal, state and local regulation of our business. In particular, both the Federal Communications Commission (“FCC”)FCC and the Federal Aviation Administration (“FAA”)FAA regulate the construction and maintenance of antenna towers and structures that support wireless communications and radio and television antennas. In addition, the FCC separately licenses and regulates wireless communications equipment and television and radio stations operating from such towers and structures. FAA and FCC regulations govern construction, lighting, painting and marking of towers and structures and may, depending on the characteristics of the tower or structure, require registration of the tower or structure. Certain proposals to construct new towers or structures or to modify existing towers or structures are reviewed by the FAA to ensure that the tower or structure will not present a hazard to air navigation.

Antenna tower owners and antenna structure owners may have an obligation to mark or paint towers or structures or install lighting to conform to FAA standards and to maintain such marking, painting and lighting. Antenna tower owners and antenna structure owners may also bear the responsibility of notifying the FAA of any lighting outages. Certain proposals to operate wireless communications and radio or television stations from antenna towers and structures are also reviewed by the FCC to ensure compliance with environmental impact requirements. Failure to comply with existing or future applicable requirements may lead to civil penalties or other liabilities and may subject us to significant indemnification liability to our customers against any such failure to comply. In addition, new regulations may impose additional costly burdens on us, which may affect our revenues and cause delays in our growth.

Local regulations, including municipal or local ordinances, zoning restrictions and restrictive covenants imposed by community developers, vary greatly, but typically require antenna tower owners and antenna structure owners to obtain approval from local officials or community standards organizations prior to tower or structure construction or modification. Local regulations can delay, prevent, or increase the cost of new construction, co-locations, or site upgrade projects, thereby limiting our ability to respond to customer demand. In addition, new regulations may be adopted that increase delays or result in additional costs to us. These factors could have a material adverse effect on our future growth and operations.

Our towers are subject to damage from natural disasters.

Our towers are subject to risks associated with natural disasters such as tornadoes and hurricanes. We maintain insurance to cover the estimated cost of replacing damaged towers, but these insurance policies are subject to loss limits and deductibles. We also maintain third party liability insurance, subject to deductibles, to protect us in the event of an accident involving a tower. A tower accident for which we are uninsured or

underinsured, or damage to a significant number of our towers, could require us to make significant capital expenditures and may have a material adverse effect on our operations or financial condition.

We could have liability under environmental laws that could have a material adverse effect on our business, financial condition and results of operations.

Our operations, like those of other companies engaged in similar businesses, are subject to the requirements of various federal, state, local and foreign environmental and occupational safety and health laws and regulations, including those relating to the management, use, storage, disposal, emission and remediation of, and exposure to, hazardous and non-hazardous substances, materials, and wastes. As owner, lessee or operator of numerous tower sites, we may be liable for substantial costs of remediating soil and groundwater contaminated by hazardous materials, without regard to whether we, as the owner, lessee or operator, knew of or were responsible for the contamination. We may be subject to potentially significant fines or penalties if we fail to comply with any of these requirements. The current cost of complying with these laws is not material to our financial condition or results of operations. However, the requirements of these laws and regulations are complex, change frequently, and could become more stringent in the future. It is possible that these requirements will change or that liabilities will arise in the future in a manner that could have a material adverse effect on our business, financial condition and results of operations.

Our dependence on our subsidiaries for cash flow may negatively affect our business.

We are a holding company with no business operations of our own. Our only significant asset is and is expected to be the outstanding capital stock of our subsidiaries. We conduct, and expect to conduct, all of our business operations through our subsidiaries. Accordingly, our ability to pay our obligations, including the principal and interest, premium, if any, and additional interest, if any, on our outstanding 10¼9 ³/4% senior discount notes and our 9¾8 ¹/2% senior discount notes, is dependent upon dividends and other distribution from our subsidiaries to us. Additionally, SBA Properties as the borrower under the CMBS Transaction must repay the components of the mortgage loan thereto. If SBA Properties’ cash flow is insufficient to cover such repayments, we may be required to refinance the mortgage loan or sell a portion or all of our interests in the 1,714 tower sites that among other things, secure along with their operating cash flows the mortgage loan. Other than the amounts required to make interest and principal payments on the notes and repayment of amounts under the CMBS Transaction, we currently expect that the earnings and cash flow of our subsidiaries will be retained and used by

them in their operations, including servicing their debt obligations. Our operating subsidiaries are separate and distinct legal entities and have no obligation, contingent or otherwise to pay the principal, interest and other amounts on the notes, or repay the components of the mortgage loan pursuant to the CMBS Transaction (other than SBA Properties, as the borrower, and SBA CMBS-1 Guarantor LLC and CMBS-1 Holdings, LLC, as guarantors), or make any funds available to us for payment. The ability of our operating subsidiaries to pay dividends or transfer assets to us may be restricted by applicable state law and contractual restrictions, including the terms of the senior credit facility.facility and the CMBS Certificates. Although the indentureindentures governing the notes will limit the ability of our operating subsidiaries to enter into consensual restrictions on their ability to pay dividends to us, these limitations are subject to a number of significant qualifications and exceptions.

As a company whose common stock is publicly traded, we are subject to the rules and regulations of federal, state and financial market exchange entities.

In response to recent laws enacted by Congress (most notably the Sarbanes-Oxley Act of 2002), some of these entities have recently issued new requirements and some are continuing to develop additional requirements (most notably, the requirements associated with Section 404 of the Sarbanes-Oxley Act). Our material internal control systems, processes and procedures will have to be in compliance with the new requirements and such compliance may require the commitment of significant financial and managerial resources and significant changes to such controls, systems, processes and procedures.None.

Availability of Reports and Other Information

Our corporate website iswww.sbasite.com. We make available, free of charge, access to our Annual Report on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, Proxy Statement on Schedule 14A and amendments to those materials filed or furnished pursuant to Section 13(a) or 15(d) of the Securities and Exchange Act of 1934 on our website under “Investor Relations—SEC Filings,” as soon as reasonably practicable after we file electronically such material with, or furnish it to, the United States Securities and Exchange Commission (the “Commission”). In addition, the Commission’s website iswww.sec.gov. The Commission makes available on this website, free of charge, reports, proxy and information statements, and other information regarding issuers, such as us, that file electronically with the Commission. Additionally, our reports, proxy and information statements may be read and copied at the Commission’s public reference room at 450 Fifth Street, NW, Washington, DC 20549. Information on our website or the Commission’s website is not part of this document.

We are headquartered in Boca Raton, Florida, where we currently lease approximately 73,000 square feet of space. We have entered into long-term leases for regional and certain site development office locations where we expect our activities to be longer-term. We open and close project offices from time to time in connection with our site development business,business. We believe our existing facilities are adequate for our current and officesplanned levels of operations and that additional office space suited for new tower build projects are generally leased for periods not to exceed 18 months.our needs is reasonably available in the markets within which we operate.

Our interests in towers are comprised of a variety of fee interests, leasehold interests created by long-term lease agreements, private easements, easements and licenses or rights-of-way granted by government entities. Of the 3,0323,304 towers in our portfolio, approximately 16%10% are located on parcels of land that we own and approximately 84%90% are located on parcels of land that have leasehold interests created by long-term lease agreements, private easements and easements, licenses or right-of-way granted by government entities. In rural areas, a wireless communications site typically consists of up to a 10,000 square foot tract, which supports towers, equipment shelters and guy wires to stabilize the structure. Less than 2,500 square feet is required for a monopole or self-supporting tower structure of the kind typically used in metropolitan areas for wireless communication tower sites. Land leases generally have an initial term of five years with five or more additional automatic renewal periods of five years, for a total of thirty years or more. In some instances, we have entered into 99 year ground leases.

ITEM 3.

LEGAL PROCEEDINGS

We are involved in various legal proceedings relating to claims arising in the ordinary course of business. We do not believe that the ultimate resolution of these matters will have a material adverse effect on our business, financial condition, results of operations or liquidity.

No matter was submitted to the vote of security holders during the fourth quarter of fiscal 2003.

2005.

PART II

The Class A common stock commenced trading under the symbol “SBAC” on The NasdaqNASDAQ National Market System (“Nasdaq”NASDAQ”) on June 16, 1999. The following table presents trading informationthe high and low bid price for the Class A common stock for the periods indicated on the Nasdaq:indicated: