Find Genealogy Records in SeaTac
Genealogy records for SeaTac residents are held primarily through King County offices and Washington State archives, since SeaTac only incorporated in 1990. Before that date, families in this area appear in unincorporated King County records. Birth registers, marriage certificates, probate files, court records, and land documents are all available through county and state repositories. This guide covers where to find SeaTac family history records, which offices handle them, and the best online tools available for your research.
SeaTac Overview
SeaTac Genealogy Through King County Records
King County is where almost all historical genealogy records for SeaTac are held. The County Auditor maintains birth and death records from 1891 to 1907 and marriage records going back to 1853. The County Clerk holds divorce records dating to 1886, probate records from 1891, and court records from 1890. These collections cover the families who lived in what is now SeaTac long before the city existed.
King County was formed from Thurston County in 1852 and its county seat is Seattle. The King County Auditor's Office is at 516 Third Ave., Room W-1033, Seattle, WA 98104, phone (206) 296-1655. The Superior Court Clerk is at King County Courthouse, 516 3rd Ave., Room E609, Seattle, WA 98104, phone (206) 296-9300. These two offices handle the bulk of genealogy requests for SeaTac and surrounding communities.
For records before July 1, 1907, the Washington State Digital Archives at digitalarchives.wa.gov has indexed collections that can be searched by name from anywhere with internet access.
Birth and Death Records for SeaTac Research
The King County Auditor birth records from 1891 to 1907 are available online through the Washington State Digital Archives. The collection contains 19,663 records and is searchable by parent names and child names. The Soundex feature helps with name spelling variations. Records outside that period can be requested from the Washington State Department of Health. Access the birth records at digitalarchives.wa.gov/Collections/TitleInfo/569.
Death records for King County from the same period are also available through the Washington State Library and the Digital Archives. The Seattle Municipal Health Department held death records from 1881 to 1907. City of Seattle death returns cover 1881 to 1907. The Washington State Library notes these early death registers in its NW Microfilm collection. For death certificates after July 1, 1907, contact the Washington State Department of Health, Center for Health Statistics, at 101 Israel Road SE, Tumwater, WA 98501, info line (360) 236-4300.
Note: The Puget Sound Regional Branch of the Washington State Archives can assist with research questions and has additional records not available online. Call (425) 564-3940 or email psbrancharchives@sos.wa.gov.
King County Marriage Records and SeaTac Family History
For SeaTac genealogy, marriage records are one of the most useful document types. King County marriage records at the Washington State Digital Archives span 1855 to 2017. The database is searchable by groom or person A name and bride or person B name, with marriage year filters. The collection covers over 150 years and has been well indexed. Find it at digitalarchives.wa.gov/Collections/TitleInfo/570.
The FamilySearch Wiki for King County, Washington Genealogy lists this collection along with King County Recorder Plats and Surveys 1870 to present, Military Records, and Historical School Districts, Registers and Censuses from 1890 to 1936. FamilySearch also holds Washington, King County Probate Records from 1854 to 1927 and Naturalization Records from 1906 to 1920.
SeaTac City Clerk Records
SeaTac incorporated in 1990 from unincorporated King County. The City Clerk maintains council minutes, ordinances, resolutions, and other municipal documents from incorporation forward. These records are administrative, but they can be useful when tracing property ownership, zoning disputes, or other matters tied to a family's history in SeaTac.
Public records requests for SeaTac city documents can be submitted through seatacwa.gov. For anything before 1990, researchers need to work through King County. The city clerk does not hold vital records. Those remain with King County or the state.
The following image is from the King County Auditor Birth Records, 1891-1907 collection at the Washington State Digital Archives, a primary resource for early SeaTac area genealogy.
This online collection contains records for births reported across King County before 1907, including families from the area now known as SeaTac.
The following image is from the Washington State Digital Archives King County Marriage Records collection, another key database for SeaTac family history research.
The collection spans 1855 to 2017 and contains marriage certificates for families throughout King County, including the communities that became SeaTac.
The following image is from the Washington State Digital Archives, showing an early King County record collection that includes vital records relevant to SeaTac area genealogy research.
These archives hold digitized collections from county auditors and court clerks going back to the 1850s.
Statewide Genealogy Resources for SeaTac
Several statewide tools support SeaTac genealogy research beyond King County offices. The Washington State Genealogical Society at wasgs.org maintains county guides and connects researchers with local volunteers. The Washington Rural Heritage project at washingtonruralheritage.org hosts digitized photographs and historical documents from communities across the state.
The Washington State Library at washstatelib.libguides.com/genealogy provides guides to county records, microfilm holdings, and online databases. The library holds microfilm of early King County vital records. Local research facilities noted for King County include the King County Archives, the Seattle Public Library, and the King County Library System. The King County Library System serves SeaTac through nearby branches and provides free access to Ancestry.com at those locations.
For federal records, census enumerations from 1850 through 1940 cover households in King County including the SeaTac area. The 1940 census and earlier records are available for free at FamilySearch and through Ancestry.com at public library branches. Military records, land patents, and immigration records available through the National Archives add another layer to SeaTac family history research.
King County Genealogy Records
SeaTac is part of King County, and the county holds the historical genealogy records for this area. King County has a deep archive of vital records, court files, probate records, and land documents reaching back to Washington Territory. For a full overview of what is available and how to access it, visit the King County genealogy page.
Nearby Cities
These cities near SeaTac share genealogy resources through King County and surrounding county archives.