Platinum Underwriters (PTP) 8-K Platinum Underwriters Holdings, LTD. Reports

Exhibit 99.1

Contact:	Lily Outerbridge
	Investor Relations
	(441) 298-0760

PLATINUM UNDERWRITERS HOLDINGS, LTD. REPORTS

FOURTH QUARTER AND YEAR ENDED DECEMBER 31, 2005

FINANCIAL RESULTS AND QUARTERLY DIVIDEND

HAMILTON, BERMUDA, FEBRUARY 26, 2006 —Platinum Underwriters Holdings, Ltd. (NYSE: PTP) today reported a net loss to common shareholders of $103.3 million, or $1.94 per basic common share, for the quarter ended December 31, 2005 and a net loss of $138.2 million, or $3.01 per basic common share, for the year ended December 31, 2005.

The results for the quarter ended December 31, 2005 include the estimated net after-tax negative impact of approximately $153.4 million from hurricane Wilma, adverse development of $30.9 million related to hurricanes Katrina and Rita, net favorable development of $12.0 million from prior years and net investment income of $37.2 million, an increase of 41.7% from the quarter ended December 31, 2004.

The results for the year ended December 31, 2005 include the aggregate estimated net after-tax negative impact of approximately $459.0 million from hurricanes Katrina, Rita and Wilma, net favorable development of $79.3 million from prior years and net investment income of $129.4 million, an increase of 53.1% from the year ended December 31, 2004.

Michael D. Price, Chief Executive Officer, commented: “2005 was the worst year on record for insured catastrophe losses and a challenging year for Platinum. Our share of these losses overshadowed the strong underwriting results in our non-catastrophe business.”

Mr. Price added, “Despite the unprecedented events of 2005, we were well-positioned for the January 1, 2006 renewal season and we competed successfully. Market conditions are good in many classes of business and we believe we have strong underwriting prospects for the remainder of the year.”

Results for the quarter ended December 31, 2005 were summarized as follows:

• Net loss was $103.3 million or $1.94 per basic common share.

• Net premiums written were $390.8 million and net premiums earned were $442.8 million.

• GAAP combined ratio was 131.9%.

• Net investment income, including interest on funds held, was $37.2 million.

1

Results for the quarter ended December 31, 2005 compared to the quarter ended December 31, 2004 were summarized as follows:

• Net loss of $103.3 million compared to net income of $49.9 million.

• Net premiums written decreased $4.1 million (or 1.0%) and net premiums earned increased $9.9 million (or 2.3%).

• GAAP combined ratio increased by 42.2 percentage points.

• Net investment income, which includes funds held, increased $11.0 million (or 41.7%).

Net premiums written for Platinum’s Property and Marine, Casualty and Finite Risk segments for the quarter ended December 31, 2005 were $121.7 million, $187.8 million and $81.3 million, respectively, representing 31.1%, 48.1% and 20.8%, respectively, of the total net premiums written. Combined ratios for these segments were 191.3%, 96.4% and 108.0%, respectively, for the quarter. Compared to the quarter ended December 31, 2004, net premiums written increased by $11.0 million (or 10.0%) for Platinum’s Property and Marine segment and $19.1 million (or 11.3%) for the Casualty segment. Net premiums written decreased by $34.2 million (or 29.6%) for the Finite Risk segment.

Results for the year ended December 31, 2005 were summarized as follows:

• Net loss was $138.2 million or $3.01 per basic common share.

• Net premiums written were $1.72 billion and net premiums earned were $1.71 billion.

• GAAP combined ratio was 114.5%.

• Net investment income, including interest on funds held, was $129.4 million.

Results for the year ended December 31, 2005 compared to the year ended December 31, 2004 were summarized as follows:

• Net loss of $138.2 million as compared to net income of $84.8 million.

• Net premiums written increased $71.7 million (or 4.4%) and net premiums earned increased by $266.8 million (or 18.4%).

• GAAP combined ratio increased by 17.8 percentage points.

• Net investment income, including interest on funds held, increased $44.9 million (or 53.1%).

Net premiums written for Platinum’s Property and Marine, Casualty and Finite Risk segments for the year ended December 31, 2005 were $575.1 million, $809.0 million and $333.6

million, respectively, representing 33.5%, 47.1% and 19.4%, respectively, of the total net premiums written. Combined ratios for these segments were 154.1%, 92.5% and 100.2%, respectively for the year. Compared to the year ended December 31, 2004, net premiums written increased by $70.6 million (or 14.0%) for Platinum’s Property and Marine segment and $131.6 million (or 19.4%) for the Casualty segment. Net premiums written decreased by $130.5 million (or 28.1%) for the Finite Risk segment.

Total assets were $5.15 billion as of December 31, 2005, an increase of $1.73 billion (or 50.6%) from $3.42 billion as of December 31, 2004. Cash and fixed maturity investments were $3.83 billion as of December 31, 2005, an increase of $1.37 billion (or 55.9%) from $2.46 billion as of December 31, 2004, due primarily to strong cash flow from operations and the receipt of the proceeds from the offerings of senior notes, common shares and mandatory convertible preferred shares issued during 2005.

Shareholders’ equity was $1.54 billion as of December 31, 2005, an increase of $407.2 million (or 35.9%) from $1.13 billion as of December 31, 2004. Book value per common share was $23.22 as of December 31, 2005 based on 59.1 million common shares outstanding, a decrease of $3.08 (or 11.7%) from $26.30 based on 43.1 million common shares outstanding as of December 31, 2004.

Quarterly Dividend

Platinum also announced that its Board of Directors has declared a quarterly dividend of $0.08 per common share, which is payable on March 31, 2006 to shareholders of record on March 2, 2006.

Financial Supplement

Platinum has posted a financial supplement on the Financial Reports page of the Investor Relations section of its website (Financial Supplement). The financial supplement provides additional detail regarding the financial performance of Platinum and its business segments.

Teleconference

Platinum will host a teleconference to discuss its financial results on Monday, February 27, 2006 at 9:00 a.m. Eastern Time. The call can be accessed by dialing 800-289-0493 (US callers) or 913-981-5510 (international callers) or in a listen-only mode via the Investor Relations section of Platinum’s website atwww.platinumre.com. Those who intend to access the teleconference should register at least ten minutes in advance to ensure access to the call.

The teleconference will be recorded and a replay will be available from 11:00 a.m. Eastern Time on Monday, February 27, 2006 until midnight Eastern Time on Monday March 6, 2006. To access the replay by telephone, dial 888-203-1112 (US callers) or 719-457-0820 (international callers) and specify passcode: 4636274. The teleconference will also be archived on the Investor Relations section of Platinum’s website atwww.platinumre.com for the same period of time.

Non-GAAP Financial Measures

In presenting the Company’s results, management has included and discussed certain schedules containing financial measures that are not calculated under standards or rules that comprise accounting principles generally accepted in the United States (GAAP). Such measures,

including segment underwriting income (or loss) and related underwriting ratios are referred to as non-GAAP. These non-GAAP measures may be defined or calculated differently by other companies. Management believes these measures, which are used to monitor the results of operations, allow for a more complete understanding of the underlying business. These measures should not be viewed as a substitute for those determined in accordance with GAAP. A reconciliation of such measures to the most comparable GAAP figures such as income before income tax expense and total shareholders’ equity is presented in the attached financial information in accordance with Regulation G.

About Platinum

Platinum Underwriters Holdings, Ltd. (NYSE: PTP) is a leading provider of property, casualty and finite risk reinsurance coverages, through reinsurance intermediaries, to a diverse clientele on a worldwide basis. Platinum operates through its principal subsidiaries in Bermuda, the United States and the United Kingdom. The Company has a financial strength rating of A (Excellent) from A.M. Best Company, Inc. For further information, please visit Platinum’s website atwww.platinumre.com.

Safe Harbor Statement Regarding Forwarding-Looking Statements

Management believes certain statements in this press release may constitute “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Forward-looking statements include all statements that do not relate solely to historical or current facts, and can be identified by the use of words such as “may,” “should,” “estimate,” “expect,” “anticipate,” “intend,” “believe,” “predict,” “potential,” or words of similar import. Forward-looking statements are necessarily based on estimates and assumptions that are inherently subject to significant business, economic and competitive uncertainties and risks, many of which are subject to change. These uncertainties and risks include, but are not limited to, conducting operations in a competitive environment; our ability to maintain our A.M. Best Company rating; significant weather-related or other natural or man-made disasters over which the Company has no control; the effectiveness of our loss limitation methods and pricing models; the adequacy of the Company’s liability for unpaid losses and loss adjustment expenses; the availability of retrocessional reinsurance on acceptable terms; our ability to maintain our business relationships with reinsurance brokers; general political and economic conditions, including the effects of civil unrest, war or a prolonged U.S. or global economic downturn or recession; the cyclicality of the property and casualty reinsurance business; market volatility and interest rate and currency exchange rate fluctuation; tax, regulatory or legal restrictions or limitations applicable to the Company or the property and casualty reinsurance business generally; and changes in the Company’s plans, strategies, objectives, expectations or intentions, which may happen at any time at the Company’s discretion. As a consequence, current plans, anticipated actions and future financial condition and results may differ from those expressed in any forward-looking statements made by or on behalf of the Company. Additionally, forward-looking statements speak only as of the date they are made, and we undertake no obligation to release publicly the results of any future revisions or updates we may make to forward-looking statements to reflect new information or circumstances after the date hereof or to reflect the occurrence of future events.

# # #

Platinum Underwriters Holdings, Ltd.
Consolidated Statements of Income and Comprehensive Income
For The Quarter and Year Ended December 31, 2005 and 2004 (Unaudited)
($ in thousands, except per share amounts)

	Three Months Ended						Twelve Months Ended
	December 31, 2005			December 31, 2004			December 31, 2005			December 31, 2004
Revenue
Net premiums earned	$	442,825		$	432,936		$	1,714,723		$	1,447,935
Net investment income		37,195			26,242			129,445			84,532
Net realized capital gains (losses)		(1,984	)		520			(3,046	)		1,955
Other income (expense)		(385	)		1,074			(586	)		3,211
Total revenue		477,651			460,772			1,840,536			1,537,633
Expenses
Losses and loss adjustment expenses		462,257			283,645			1,505,425			1,019,804
Acquisition expenses		107,100			94,935			403,135			327,821
Other underwriting expenses		14,467			10,053			55,669			53,137
Corporate expenses		3,792			2,844			14,158			13,196
Net foreign currency exchange (gains) losses		241			(399	)		2,111			(725	)
Interest expense		6,820			2,316			20,006			9,268
Loss on repurchase of debt		2,486			—			2,486			—
Total expenses		597,163			393,394			2,002,990			1,422,501
Income (loss) before income tax expense		(119,512	)		67,378			(162,454	)		115,132
Income tax expense (benefit)		(16,976	)		17,456			(24,967	)		30,349
Net income (loss)		(102,536	)		49,922			(137,487	)		84,783
Preferred dividends		737			—			737			—
Net income (loss) available to common shareholders	$	(103,273	)	$	49,922		$	(138,224	)	$	84,783
Basic
Weighted average shares outstanding		53,339			43,073			45,915			43,158
Basic earnings (loss) per share	$	(1.94	)	$	1.16		$	(3.01	)	$	1.96
Diluted
Weighted average shares outstanding		53,339			49,819			45,915			50,261
Diluted earnings (loss) per share	$	(1.94	)	$	1.03		$	(3.01	)	$	1.81
Comprehensive income (loss)
Net income (loss)	$	(102,536	)	$	49,922		$	(137,487	)	$	84,783
Other comprehensive income (loss), net of tax		(15,000	)		(4,193	)		(52,970	)		(6,522	)
Comprehensive income (loss)	$	(117,536	)	$	45,729		$	(190,457	)	$	78,261

Platinum Underwriters Holdings, Ltd.
Condensed Consolidated Balance Sheets
As of December 31, 2005 and 2004
($ in thousands, except per share data)

	December 31, 2005		December 31, 2004
Assets
Investments	$	3,000,889	$	2,246,971
Short term investments and cash and cash equivalents		829,539		209,897
Receivables		567,449		580,048
Accrued investment income		29,230		23,663
Reinsurance balances (prepaid and recoverable)		76,109		4,892
Deferred acquisition costs		130,800		136,038
Funds held		291,629		198,048
Other assets		228,730		22,438
Total assets	$	5,154,375	$	3,421,995
Liabilities
Unpaid losses and loss adjustment expenses	$	2,323,990	$	1,380,955
Unearned premiums		502,018		502,423
Debt obligations		292,840		137,500
Commissions payable		186,654		181,925
Other liabilities		308,624		86,189
Total liabilities		3,614,126		2,288,992
Total shareholders’ equity		1,540,249		1,133,003
Total liabilities and shareholders’ equity	$	5,154,375	$	3,421,995
Book value per common share	$	23.22	$	26.30

Platinum Underwriters Holdings, Ltd.
Segment Reporting
For the Three Months Ended December 31, 2005 and 2004 (Unaudited)
($ in thousands)

Three Months Ended December 31, 2005

	Property
	and Marine			Casualty			Finite Risk			Total
Segment underwriting results
Net premiums written	$	121,703			187,813			81,262		$	390,778
Net premiums earned		154,454			201,088			87,283			442,825
Losses and loss adjustment expenses		264,442			136,422			61,393			462,257
Acquisition expenses		24,546			51,135			31,419			107,100
Other underwriting expenses		6,479			6,511			1,477			14,467
Total underwriting expenses		295,467			194,068			94,289			583,824
Segment underwriting income (loss)	$	(141,013	)		7,020			(7,006	)		(140,999	)
Net investment income											37,195
Net realized capital losses											(1,984	)
Net foreign currency exchange losses											(241	)
Other expense											(385	)
Corporate expenses not allocated to segments											(3,792	)
Interest expense											(6,820	)
Loss on repurchase of debt											(2,486	)
Loss before income tax benefit										$	(119,512	)
GAAP underwriting ratios:
Losses and LAE		171.2	%		67.8	%		70.3	%		104.4	%
Acquisition expense		15.9	%		25.4	%		36.0	%		24.2	%
Other underwriting expense		4.2	%		3.2	%		1.7	%		3.3	%
Combined		191.3	%		96.4	%		108.0	%		131.9	%
Three Months Ended December 31, 2004
Segment underwriting results
Net premiums written	$	110,675			168,706			115,504		$	394,885
Net premiums earned		131,712			186,929			114,295			432,936
Losses and loss adjustment expenses		64,510			124,621			94,514			283,645
Acquisition expenses		18,869			45,884			30,182			94,935
Other underwriting expenses		6,547			3,107			399			10,053
Total underwriting expenses		89,926			173,612			125,095			388,633
Segment underwriting income (loss)	$	41,786			13,317			(10,800	)		44,303
Net investment income											26,242
Net realized capital gains											520
Net foreign currency exchange gains											399
Other income											1,074
Corporate expenses not allocated to segments											(2,844	)
Interest expense											(2,316	)
Income before income tax expense										$	67,378
GAAP underwriting ratios:
Losses and LAE		49.0	%		66.7	%		82.7	%		65.5	%
Acquisition expense		14.3	%		24.5	%		26.4	%		21.9	%
Other underwriting expense		5.0	%		1.7	%		0.3	%		2.3	%
Combined		68.3	%		92.9	%		109.4	%		89.7	%

The GAAP underwriting ratios are calculated by dividing each item above by net premiums earned.

Platinum Underwriters Holdings, Ltd.
Segment Reporting
For the Year Ended December 31, 2005 and 2004 (Unaudited)
($ in thousands)

Twelve Months Ended December 31, 2005

	Property
	and Marine			Casualty			Finite Risk			Total
Segment underwriting results
Net premiums written	$	575,055			809,031			333,636		$	1,717,722
Net premiums earned		569,173			789,629			355,921			1,714,723
Losses and loss adjustment expenses		756,742			511,609			237,074			1,505,425
Acquisition expenses		93,983			194,397			114,755			403,135
Other underwriting expenses		26,074			24,690			4,905			55,669
Total underwriting expenses		876,799			730,696			356,734			1,964,229
Segment underwriting income (loss)	$	(307,626	)		58,933			(813	)		(249,506	)
Net investment income											129,445
Net realized capital losses											(3,046	)
Net foreign currency exchange losses											(2,111	)
Other expense											(586	)
Corporate expenses not allocated to segments											(14,158	)
Interest expense											(20,006	)
Loss on repurchase of debt											(2,486	)
Loss before income tax benefit										$	(162,454	)
GAAP underwriting ratios:
Losses and LAE		133.0	%		64.8	%		66.6	%		87.8	%
Acquisition expense		16.5	%		24.6	%		32.2	%		23.5	%
Other underwriting expense		4.6	%		3.1	%		1.4	%		3.2	%
Combined		154.1	%		92.5	%		100.2	%		114.5	%
Twelve Months Ended December 31, 2004
Segment underwriting results
Net premiums written	$	504,439			677,399			464,175		$	1,646,013
Net premiums earned		485,135			611,893			350,907			1,447,935
Losses and loss adjustment expenses		349,557			418,355			251,892			1,019,804
Acquisition expenses		76,360			151,649			99,812			327,821
Other underwriting expenses		27,827			19,086			6,224			53,137
Total underwriting expenses		453,744			589,090			357,928			1,400,762
Segment underwriting income (loss)	$	31,391			22,803			(7,021	)		47,173
Net investment income											84,532
Net realized capital gains											1,955
Net foreign currency exchange gains											725
Other income											3,211
Corporate expenses not allocated to segments											(13,196	)
Interest expense											(9,268	)
Income before income tax expense										$	115,132
GAAP underwriting ratios:
Losses and LAE		72.1	%		68.4	%		71.8	%		70.4	%
Acquisition expense		15.7	%		24.8	%		28.4	%		22.6	%
Other underwriting expense		5.7	%		3.1	%		1.8	%		3.7	%
		93.5	%		96.3	%		102.0	%		96.7	%

The GAAP underwriting ratios are calculated by dividing each item above by net premiums earned.