QuickLinks -- Click here to rapidly navigate through this document

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 8-K/A

Current Report Pursuant
to Section 13 or 15(d) of the
Securities Exchange Act of 1934

Date of Report:  January 23, 2003

Washington Mutual, Inc.
(Exact name of registrant as specified in its charter)

Washington
(State or other jurisdiction
of incorporation)		   1-14667
(Commission File
Number)		   91-1653725
(I.R.S. Employer
Identification No.)

1201 Third Avenue, Seattle, Washington
(Address of principal executive offices)
 
98101
(Zip Code)

(206) 461-2000
(Registrant's telephone number, including area code)


ITEM 9.    Regulation FD Disclosure.

        On January 21, 2003, Washington Mutual, Inc. issued a press release announcing the results of its operations for the fourth quarter and the year ended December 31, 2002. In that press release, the consolidated statements of income included the separate presentation of interest income on loans held for sale and interest income on loans held in portfolio. Those amounts have been revised and are hereby amended in the following Consolidated Statements of Income. These revisions did not affect total interest income and thus had no impact on net income.

Washington Mutual, Inc.
Consolidated Statements of Income
(dollars in millions, except per share data)
(unaudited)

 
   Quarter Ended
   Year Ended
  
 
   Dec. 31,
2002
   Sept. 30,
2002
   Dec. 31,
2001
   Dec. 31,
2002
   Dec. 31,
2001
  
Interest Income                                
  Loans held for sale   $ 532   $ 388   $ 411   $ 1,724   $ 1,203  
  Loans held in portfolio     2,219     2,287     2,279     9,252     10,030  
  Available-for-sale ("AFS") securities     547     652     776     2,959     3,573  
  Other interest and dividend income     68     86     59     312     259  
   
 
 
 
 
 
    Total interest income     3,366     3,413     3,525     14,247     15,065  

Interest Expense
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  Deposits     672     679     649     2,668     3,094  
  Borrowings     768     815     849     3,238     5,095  
   
 
 
 
 
 
    Total interest expense     1,440     1,494     1,498     5,906     8,189  
   
 
 
 
 
 
      Net interest income     1,926     1,919     2,027     8,341     6,876  
Provision for loan and lease losses     125     135     200     595     575  
   
 
 
 
 
 
      Net interest income after provision for loan and lease losses     1,801     1,784     1,827     7,746     6,301  

Noninterest Income
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  Depositor and other retail banking fees     449     426     353     1,634     1,290  
  Securities fees and commissions     90     92     77     362     303  
  Insurance income     45     46     35     177     100  
  Home loan mortgage banking expense, net     (178 )   (1,575 )   (690 )   (2,094 )   (285 )
  Portfolio loan related income     123     85     60     349     193  
  Gain from other AFS securities     574     356     392     768     600  
  Revaluation gain (loss) from derivatives     (28 )   1,582     —     2,396     (5 )
  Gain (loss) on extinguishment of securities sold under agreements to repurchase ("repurchase agreements")     (11 )   98     496     282     621  
  Net settlement income from certain interest-rate swaps     158     116     —     382     —  
  Other income     172     154     107     534     431  
   
 
 
 
 
 
    Total noninterest income     1,394     1,380     830     4,790     3,248  

2


Noninterest Expense
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  Compensation and benefits     757     719     535     2,899     1,924  
  Occupancy and equipment     294     289     228     1,153     804  
  Telecommunications and outsourced information services     115     136     119     524     441  
  Depositor and other retail banking losses     51     55     45     204     144  
  Amortization of goodwill     —     —     37     —     139  
  Amortization of other intangible assets     16     17     8     67     33  
  Professional fees     47     55     63     208     201  
  Advertising and promotion     58     75     50     246     185  
  Other expense     320     270     246     1,081     746  
   
 
 
 
 
 
    Total noninterest expense     1,658     1,616     1,331     6,382     4,617  
   
 
 
 
 
 
      Income before income taxes     1,537     1,548     1,326     6,154     4,932  
Income taxes     568     567     484     2,258     1,818  
   
 
 
 
 
 
Net Income   $ 969   $ 981   $ 842   $ 3,896   $ 3,114  
   
 
 
 
 
 
Net Income Attributable to Common Stock   $ 969   $ 980   $ 840   $ 3,891   $ 3,107  
   
 
 
 
 
 

Net income per common share:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  Basic   $ 1.05   $ 1.04   $ 0.98   $ 4.12   $ 3.65  
  Diluted     1.03     1.02     0.97     4.05     3.59  

Dividends declared per common share
 
$
0.28
 
$
0.27
 
$
0.24
 
$
1.06
 
$
0.90
 

Basic weighted average number of common shares outstanding (in thousands)
 
 
926,210
 
 
947,293
 
 
856,014
 
 
943,905
 
 
850,245
 
Diluted weighted average number of common shares outstanding (in thousands)     939,991     963,422     868,951     960,152     864,658  

3

    WASHINGTON MUTUAL, INC.

Date:  January 23, 2003
 
By:
 
/s/  FAY L. CHAPMAN      
Fay L. Chapman
 Senior Executive Vice President

4



QuickLinks