NASDAQ: BOKF
                                                               Exhibit 99 (a)


For Further Information Contact:               Steven Nell
                                               Chief Financial Officer
                                               BOK Financial Corp.
                                               (918) 588-6319

                                               Danny M. Boyd
                                               Corporate Communications
                                               BOK Financial Corp.
                                               (918) 588-6348

                  BOK Financial Continues Earnings Growth Trend
            Regional Market Share Advances Through Strong Loan Growth

     TULSA,  Okla.  (Tuesday,  Oct.  18,  2005) - Strong loan growth in regional
markets contributed to third quarter performance at BOK Financial Corporation.

     The company  reported net income of $50.8 million,  or 76 cents per diluted
share, for the third quarter of 2005,  compared with $47.8 million,  or 72 cents
per  share for the third  quarter  of 2004.  Year-to-date  net  income  for 2005
totaled $153.3  million,  up 16 percent over last year.  Earnings per share were
$2.29 for the first nine months of 2005 compared with $1.99 last year.

     Outstanding  loan  balances  grew $369  million  since June 30,  2005, a 17
percent  annualized  growth  rate.  Commercial  loans  increased  $208  million,
including $121 million of loans to the services  sector of the portfolio and $72
million in energy loans.  Commercial  real estate loans  increased $111 million.
Loans to single  family  homebuilders  grew $64 million  while loans  secured by
commercial office buildings increased $41 million.

     "Texas  continues  to be a vibrant  growth  market for the  company,"  said
President and CEO Stan  Lybarger.  "Annualized  loan growth in Texas exceeded 28
percent,  up from 22 percent in the second  quarter.  The company also added $32
million  of  outstanding  loans  in the  Phoenix  market.  The  third  quarter's
successful  completion of Bank of Arizona's  processing  systems conversion will
support further expansion in Arizona."

                                     -more-

Page 2- BOK Financial Earnings

     Net interest revenue  increased $4.4 million,  or 4 percent,  compared with
the third  quarter  of 2004 due to growth in  average  earning  assets.  Average
earning  assets  increased  $1.2 billion,  or 9 percent,  including a 13 percent
increase  in average  loans.  The growth in  average  earning  assets was funded
primarily  by a $799  million  increase  in  borrowed  funds and a $423  million
increase in deposits.

     Net interest  margin was 3.32 percent for the third quarter,  down 18 basis
points  from the  third  quarter  of 2004 and 13 basis  points  from the  second
quarter of 2005. The decreased net interest margin reflected strong loan growth,
primarily  over the past two quarters.  Loan growth has exceeded  deposit growth
over the past six months,  resulting in a shift in funding mix from  deposits to
short-term  borrowed funds. The net spread of this activity  generated solid net
interest revenue growth, but reduced the net interest margin eight basis points.
Net  interest  margin also  decreased  three  basis  points due to a $92 million
increase in average  margin assets the company  carries in support of its energy
derivatives  business.  Fees earned on margin assets, which totaled $2.4 million
in the third  quarter of 2005,  are included in  non-interest  revenue while the
related cost of funds is included in interest expense.

     The company  continued  to position  its  balance  sheet to be  essentially
interest rate neutral.  Securities and short-term  borrowings are used to offset
the  asset-sensitive  nature of loans and deposits.  This strategy mitigates the
effect of changes in interest  rates and the  flattened  yield  curve.  However,
changes in funding mix and competitive  pressure on loan and deposit pricing may
reduce the net interest margin.

     Non-interest revenue from fees and commissions  increased $12.1 million, or
15  percent  compared  to the same  period  last  year.  This  source of revenue
represented  45 percent of total revenue in the third quarter of 2005,  compared
with 42 percent in 2004. In addition to the $2.4 million increase in fees earned
on margin assets,  mortgage banking and transaction card revenues increased $2.9
million and $1.8 million,  respectively.  Growth in mortgage banking revenue was
driven by  increased  volume of loans  funded  and sold,  partially  offset by a
continued  decline in servicing  revenue.  Check card and merchant discount fees
provided the growth in transaction card revenue.

                                     -more-

Page 3-BOK Financial Earnings

     A $4.0  million  provision  for credit  losses was  recorded  for the third
quarter of 2005,  compared  with $5.0 million for the third  quarter of 2004 and
$2.0  million  for the second  quarter of 2005.  Net  charge-offs  totaled  $3.3
million  in 2005  compared  with $4.8  million  in 2004 and $2.3  million in the
preceding quarter.

     "The  company  continues  to benefit  from  strong  credit  quality,"  said
Lybarger.  "Nonperforming  and problem loans  continue to decline due to general
economic conditions and receipt of payments on problem loans."

     Reserves for credit losses, which include the allowance for loan losses and
a reserve for credit risk on  unfunded  loans,  totaled  $127  million,  or 1.44
percent of outstanding  loans and 341 percent of  non-performing  loans at Sept.
30,  2005.  The  combined  reserves  for  credit  losses  were 1.50  percent  of
outstanding  loans and 313  percent  of  nonperforming  loans at June 30,  2005.
Nonperforming  loans  totaled $37 million at Sept.  30, 2005,  down $3.2 million
since June 30, 2005 due to payments received.

     Operating  expenses  totaled  $117.0  million for the third quarter of 2005
compared  with $114.2  million for the same period of 2004.  The  provision  for
impairment  of  mortgage  servicing  rights  decreased  $10.6  million as rising
mortgage interest rates increased the value of the servicing  rights.  Excluding
the provision for mortgage servicing rights,  operating expenses increased $13.4
million or 12 percent.  Personnel costs  increased $6.0 million,  or 10 percent.
Regular  compensation  expense increased $4.8 million, or 14 percent, due to a 7
percent  increase in average  compensation per employee and a 7 percent increase
in staffing levels.  Growth in personnel costs reflected the company's continued
expansion, primarily in Texas and Arizona.

     BOK  Financial  is a regional  financial  services  company  that  provides
commercial  and  consumer  banking,  investment  and  trust  services,  mortgage
origination and servicing,  and an electronic funds transfer  network.  Holdings
include Bank of  Albuquerque,  N.A.,  Bank of Arizona,  N.A.,  Bank of Arkansas,
N.A.,  Bank of Oklahoma,  N.A.,  Bank of Texas,  N.A.,  Colorado  State Bank and
Trust,  N.A., BOSC, Inc. and the TransFund  electronic funds network.  Shares of
BOK  Financial  are  traded  on the  NASDAQ  under  the  symbol  BOKF.  For more
information, visit our website at www.bokf.com.

                                     -more-

Page 4-BOK Financial Earnings

     This news release  contains  forward-looking  statements  that are based on
management's  beliefs,   assumptions,   current   expectations,   estimates  and
projections  about BOK Financial Corp., the financial  services industry and the
economy  generally.  Words  such  as  "anticipates,"  "believes,"  ""estimates,"
"expects,"  "forecasts,"  ""plans,"  "projects,"  variations  of such  words and
similar  expressions are intended to identify such  forward-looking  statements.
Management  judgments relating to, and discussion of the provision and allowance
for credit  losses  involve  judgments  as to future  events and are  inherently
forward-looking  statements.  Assessments that BOK Financial's  acquisitions and
other growth endeavors will be profitable are necessary  statements of belief as
to the outcome of future events based in part on information  provided by others
which BOK Financial has not  independently  verified.  These  statements are not
guarantees of future performance and involve certain risks,  uncertainties,  and
assumptions  which are  difficult  to predict  with  regard to  timing,  extent,
likelihood and degree of occurrence.  Therefore, actual results and outcomes may
materially  differ  from  what  is  expected,  implied  or  forecasted  in  such
forward-looking statements.  Internal and external factors that might cause such
a difference  include,  but are not limited to (1) the ability to fully  realize
expected  cost  savings from mergers  within the expected  time frames,  (2) the
ability of other  companies on which BOK  Financial  relies to provide goods and
services in a timely and  accurate  manner,  (3)  changes in interest  rates and
interest  rate  relationships,  (4) demand for  products and  services,  (5) the
degree of  competition  by  traditional  and  non-traditional  competitors,  (6)
changes in banking regulations,  tax laws, prices, levies, and assessments,  (7)
the impact of  technological  advances,  and (8) trends in customer  behavior as
well as  their  ability  to  repay  loans.  BOK  Financial  Corporation  and its
affiliates undertake no obligation to update, amend, or clarity  forward-looking
statements, whether as a result of new information, future events or otherwise.


                                      -30-