<ARTICLE>                                                                 9
<LEGEND>   THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED
FROM THE CONSOLIDATED FINANCIAL STATEMENTS OF FIRSTBANK CORPORATION FOR THE
PERIOD ENDED SEPTEMBER 30, 1998, AND IS QUALIFIED IN ITS ENTIRETY BY
REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER>                                                          1,000
       
                                                            
<PERIOD-TYPE>                                                         9-MOS
<FISCAL-YEAR-END>                                               DEC-31-1998
<PERIOD-START>                                                  JAN-01-1998
<PERIOD-END>                                                    SEP-30-1998
<CASH>                                                               19,860
<INT-BEARING-DEPOSITS>                                                  414
<FED-FUNDS-SOLD>                                                     38,513
<TRADING-ASSETS>                                                          0
<INVESTMENTS-HELD-FOR-SALE>                                          88,962
<INVESTMENTS-CARRYING>                                                    0
<INVESTMENTS-MARKET>                                                      0
<LOANS>                                                             420,654
<ALLOWANCE>                                                           8,734
<TOTAL-ASSETS>                                                      592,949
<DEPOSITS>                                                          494,097
<SHORT-TERM>                                                         18,021
<LIABILITIES-OTHER>                                                  22,654
<LONG-TERM>                                                               0
<COMMON>                                                             45,756
<PREFERRED-MANDATORY>                                                     0
<PREFERRED>                                                               0
<OTHER-SE>                                                           12,420
<TOTAL-LIABILITIES-AND-EQUITY>                                      592,949
<INTEREST-LOAN>                                                      28,675
<INTEREST-INVEST>                                                     3,831
<INTEREST-OTHER>                                                        475
<INTEREST-TOTAL>                                                     32,981
<INTEREST-DEPOSIT>                                                   13,350
<INTEREST-EXPENSE>                                                   14,415
<INTEREST-INCOME-NET>                                                18,566
<LOAN-LOSSES>                                                           815
<SECURITIES-GAINS>                                                        3
<EXPENSE-OTHER>                                                      14,278
<INCOME-PRETAX>                                                       7,749
<INCOME-PRE-EXTRAORDINARY>                                            7,749
<EXTRAORDINARY>                                                           0
<CHANGES>                                                                 0
<NET-INCOME>                                                          5,431
<EPS-PRIMARY>                                                          1.26
<EPS-DILUTED>                                                          1.21
<YIELD-ACTUAL>                                                         5.12
<LOANS-NON>                                                             306
<LOANS-PAST>                                                            678
<LOANS-TROUBLED>                                                        214
<LOANS-PROBLEM>                                                       1,198
<ALLOWANCE-OPEN>                                                      8,114
<CHARGE-OFFS>                                                           522
<RECOVERIES>                                                            327
<ALLOWANCE-CLOSE>                                                     8,734
<ALLOWANCE-DOMESTIC>                                                  6,488
<ALLOWANCE-FOREIGN>                                                       0
<ALLOWANCE-UNALLOCATED>                                               2,246