| Rank | County | Income Per Household | 
                            
                                
                                    | 1 | King County, Washington | $70,567 | 
                            
                                
                                    | 2 | Snohomish County, Washington | $67,777 | 
                            
                                
                                    | 3 | Thurston County, Washington | $63,129 | 
                            
                                
                                    | 4 | Kitsap County, Washington | $61,112 | 
                            
                                
                                    | 5 | Benton County, Washington | $59,974 | 
                            
                                
                                    | 6 | Island County, Washington | $59,328 | 
                            
                                
                                    | 7 | Clark County, Washington | $59,051 | 
                            
                                
                                    | 8 | Pierce County, Washington | $58,824 | 
                            
                                
                                    | 9 | Skagit County, Washington | $55,555 | 
                            
                                
                                    | 10 | Skamania County, Washington | $52,884 | 
                            
                                
                                    | 11 | San Juan County, Washington | $51,395 | 
                            
                                
                                    | 12 | Whatcom County, Washington | $51,389 | 
                            
                                
                                    | 13 | Franklin County, Washington | $50,731 | 
                            
                                
                                    | 14 | Douglas County, Washington | $49,707 | 
                            
                                
                                    | 15 | Chelan County, Washington | $49,509 | 
                            
                                
                                    | 16 | Spokane County, Washington | $49,257 | 
                            
                                
                                    | 17 | Mason County, Washington | $48,912 | 
                            
                                
                                    | 18 | Garfield County, Washington | $47,379 | 
                            
                                
                                    | 19 | Jefferson County, Washington | $46,887 | 
                            
                                
                                    | 20 | Walla Walla County, Washington | $46,793 | 
                            
                                
                                    | 21 | Lincoln County, Washington | $46,765 | 
                            
                                
                                    | 22 | Cowlitz County, Washington | $46,461 | 
                            
                                
                                    | 23 | Clallam County, Washington | $46,212 | 
                            
                                
                                    | 24 | Yakima County, Washington | $44,419 | 
                            
                                
                                    | 25 | Lewis County, Washington | $44,373 | 
                            
                                
                                    | 26 | Stevens County, Washington | $44,354 | 
                            
                                
                                    | 27 | Grant County, Washington | $44,237 | 
                            
                                
                                    | 28 | Columbia County, Washington | $44,038 | 
                            
                                
                                    | 29 | Kittitas County, Washington | $42,769 | 
                            
                                
                                    | 30 | Grays Harbor County, Washington | $42,729 | 
                            
                                
                                    | 31 | Asotin County, Washington | $41,993 | 
                            
                                
                                    | 32 | Adams County, Washington | $41,219 | 
                            
                                
                                    | 33 | Wahkiakum County, Washington | $41,149 | 
                            
                                
                                    | 34 | Pacific County, Washington | $40,599 | 
                            
                                
                                    | 35 | Okanogan County, Washington | $40,537 | 
                            
                                
                                    | 36 | Pend Oreille County, Washington | $38,922 | 
                            
                                
                                    | 37 | Klickitat County, Washington | $38,774 | 
                            
                                
                                    | 38 | Ferry County, Washington | $35,684 | 
                            
                                
                                    | 39 | Whitman County, Washington | $35,409 |