The list below includes links to existing online marriage indexes for each county in Washington state. In order to research marriage certificates that are not online, you will have to contact the county auditor where the certificate would be filed.  Some counties keep their older marriage certificates at regional branches of the Washington State Archives.

Marriage certificates prior to 1947 are filed in the counties where the marriages took place.  Marriage certificates 1947 to present are filed in the counties where the licenses are issued.

Adams County
Western States Marriage Index	1884-1905: index only
Washington State Digital Archives	1884-present: index and images
Asotin County
Western States Marriage Index	1884-1907: index only
Washington State Digital Archives	1899-2003: index and images
Benton County
Washington State Digital Archives	1905-1980: index and images
Benton County Auditor	1985-present: index only
Chelan County
Washington State Digital Archives	1900-2003: index and images
Chelan County Auditor	1888-present: index and images
Clallam County
Clallam County Auditor	1891-present: index and images
Washington State Digital Archives	1977-2010: index and images
Clark County
Western States Marriage Index	1840-1903: index only
Washington State Digital Archives	1889-1998: index and images
Clark County Auditor	1998-present: index only
Columbia County
Western States Marriage Index	1876-1912: index only
Washington State Digital Archives	1876-2003: index and images
Cowlitz County
Western States Marriage Index	1854-1887: index only
Cowlitz County Auditor	1854-present: index and images
Washington State Digital Archives	2009-present: index and images
Douglas County
Western States Marriage Index	1877-1900: index only
Washington State Digital Archives	1884-1975: index and images
Douglas County Auditor	1987-present: index and images
Ferry County
Washington State Digital Archives	1900-1999: index and images
Franklin County
Western States Marriage Index	1892-1906: index only
Washington State Digital Archives	1890-1909: index only 1910-1930: index and images 1931-1999: index only 1999-present: index and images
Garfield County
Western States Marriage Index	1882-1889: index only
Washington State Digital Archives	1882-1990: index and images
Grant County
Washington State Digital Archives	1909-1993: index and images
Grays Harbor County
Western States Marriage Index	1855-2000: index only
Washington State Digital Archives	1870-present: index and images
Island County
Washington State Digital Archives	1855-1994: index and images
Jefferson County
Washington State Digital Archives	1872-present: index and images
Jefferson County Auditor	1984-present: index and images
King County
Washington State Digital Archives	1855-1989: index and images
King County Recorder's Office	1979-present: index only
Kitsap County
Washington State Digital Archives	1860-1990: index and images 1991-2006: index only
Kitsap County Auditor	1986-2005: index only 2006-present: index and images
Kittitas County
Washington State Digital Archives	1891-2005: index and images
Klickitat County
Western States Marriage Index	1867-1941: index only
Washington State Digital Archives	1867-present: index and images
Lewis County
Washington State Digital Archives	1854-present: index and images
Lewis County Auditor	1854-present: index and images
Lincoln County
Western States Marriage Index	1884-1887: index only
Washington State Digital Archives	1883-2004: index and images
Mason County
Washington State Digital Archives	1857-1985: index and images 1986-present: index only
Mason County Auditor	1975-present: index only
Okanogan County
no known online indexing
Pacific County
Washington State Digital Archives	1872-1947: index and images 1996-present: index and images
Pend Oreille County
Western States Marriage Index	1911-1915: index only
Washington State Digital Archives	1911-2004: index and images
Pierce County
Washington State Digital Archives	1889-1947: index and images 1984-2008: index only
Pierce County Auditor	1983-present: index only
Pierce County Auditor Index Book Images	1859-1980: index images only
San Juan County
Washington State Digital Archives	1874-1914: index only 1923-1939: index and images
Skagit County
Washington State Digital Archives	1884-2000: index and images
Skagit County Auditor	1981-present: index only
Skamania County
Western States Marriage Index	1893-1900: index only
Washington State Digital Archives	1905-2007: index and images
Snohomish County
Washington State Digital Archives	1873-1919 & 1968-1985: index and images
Snohomish County Auditor	1985-present: index only
Spokane County
Western States Marriage Index	1880-1917: index only
Washington State Digital Archives	1880-present: index and images
Spokane County Auditor	1881-present: index only
Stevens County
Western States Marriage Index	1859-1891: index only
Washington State Digital Archives	1859-2008: index and images
Thurston County
Washington State Digital Archives	1970-2004: index only
Thurston County Auditor	1970-present: index only
Wahkiakum County
no known online indexing
Walla Walla County
Western States Marriage Index	1862-1910: index only
Washington State Digital Archives	1865-1986: index and images 1987-2007: index only
Whatcom County
Western States Marriage Index	1878-1902: index only
Washington State Digital Archives	1869-2001: index and images
Whitman County
Western States Marriage Index	1872-1909: index only
Washington State Digital Archives	1872-2002: index and images
Yakima
Washington State Digital Archives	1896-1930: index and images 1931-2008: index only