Methods for Finding Property Lines in Washington
Washington property owners have several practical tools for researching where their property lines are. These range from free online resources to hiring a licensed surveyor for a legally definitive answer. The right approach depends on what you are trying to accomplish.
For general reference, GIS maps and plat records are a good starting point. For anything that involves construction, fencing, or a legal dispute, only a licensed Professional Land Surveyor can provide a definitive and legally defensible answer.
Washington County GIS Portals
Every county in Washington maintains a GIS (geographic information system) portal that displays parcel boundaries overlaid on aerial photography and other map layers. These are free, publicly accessible, and useful for getting a general picture of your property's shape and location relative to neighboring parcels.
King County GIS (iMap)
King County's iMap portal at kingcounty.gov/services/gis/Maps is one of the most robust county GIS systems in the state. You can search by address or parcel number, view parcel boundaries, pull up recorded plat maps, and access a range of property data layers including zoning, flood zones, and critical areas. The Assessor's eReal Property portal at blue.kingcounty.gov/Assessor/eRealProperty links parcel data to assessment records, deed history, and permit records.
Spokane County GIS
Spokane County's online GIS at gis.spokanecounty.org provides parcel search by address or parcel number with aerial photography and parcel boundary overlays. The County Assessor's website at spokanecounty.org/assessor links to parcel details including ownership, legal description, and recorded documents.
Pierce County
Pierce County Assessor-Treasurer at piercecountywa.gov/assessortax provides parcel search tools with legal descriptions, plat information, and links to recorded documents. Pierce County's GIS map viewer shows parcel boundaries with aerial imagery for all properties in the county including Tacoma, Puyallup, and Gig Harbor.
Snohomish County
Snohomish County's online property search at snohomishcountywa.gov/assessor allows parcel lookup by address or parcel number. The county GIS viewer shows parcel boundaries with multiple background map layers. Snohomish County also provides access to recorded survey documents through its document search portal.
Clark County
Clark County's GIS portal at gis.clark.wa.gov provides parcel search and aerial map viewing for all properties in the Vancouver metro area and surrounding county. The Assessor's website links to property cards with legal descriptions and recorded plat references.
Washington State Parcel Database
The Washington State Department of Revenue maintains a statewide parcel database that aggregates parcel data from all 39 counties. The data is available at dor.wa.gov through the GIS open data portal. This database is useful for finding basic ownership information, parcel acreage, and tax data across county lines, but the boundary locations are only as accurate as each county's GIS data, which is not survey-accurate.
County Auditor Records: Plats and Surveys
Recorded plat maps and Records of Survey filed under RCW 58.09 are maintained by county auditors. These are the most legally significant documents for understanding where your property lines are, because they represent the formal record of how land was divided and surveyed.
Most Washington county auditors have online document search portals. Search by your parcel number, address, or the legal description shown on your deed to find recorded plats and surveys affecting your property. Key portals:
- King County Recorder: recordsearch.kingcounty.gov for recorded documents including plats and surveys.
- Pierce County Auditor: Online document search at piercecountywa.gov/auditor.
- Snohomish County Auditor: Document search at snohomishcountywa.gov/auditor.
- Spokane County Auditor: Document portal at spokanecounty.org/auditor.
- Whatcom County Auditor: Online search at whatcomcounty.us/auditor.
For counties without online search, you can visit the county auditor's office in person or contact them to request copies of recorded documents.
Your Deed and Legal Description
Your property deed contains a legal description that defines the parcel's boundaries. For properties in platted subdivisions, the description references the plat name, lot number, and block number (for example: “Lot 4, Block 12, Riverside Plat No. 3, recorded in Volume 45 of Plats, Page 22”). For rural properties, the description may use metes and bounds or PLSS township and range references.
The deed's legal description is your starting point for understanding the property's extent. However, translating a deed description into physical ground locations requires professional surveying skills. Deed language alone does not tell you where to place a stake.
Locating Physical Monuments on the Ground
If your property has been previously surveyed, corner monuments may still be in the ground. Common monument types in Washington include iron rebar or pipe with a PLS cap stamped with the surveyor's license number, concrete monuments for section corners, and aluminum caps set in concrete for subdivision corners.
You can look for these monuments yourself. A metal detector helps locate buried iron pins. Property corners in platted subdivisions are often set 6 to 12 inches below grade. If you find a pin, note the stamped information on any cap, which identifies the surveyor and survey date.
Finding a physical monument does not confirm it marks your specific corner. Monuments from adjacent properties, road construction, or utility work may be nearby and could be mistaken for property corners. A licensed PLS can confirm whether a monument you have found is in fact your property corner.
When Online Research Is Not Enough
GIS maps and online records are useful for research, but they have clear limitations:
- GIS parcel boundaries are digitized from deed descriptions and plat records, not from physical surveys. They can be off by several feet or more, especially for older parcels.
- Plat maps show the intended layout when the subdivision was recorded. They do not reflect decades of monument disturbance, road construction, or utility work that may have affected the physical markers on the ground.
- Metes and bounds descriptions for rural parcels may reference natural features (trees, streams, rocks) that have changed or disappeared.
For any situation involving construction, fencing, or a legal dispute, hire a licensed Washington PLS. A boundary survey produces a legally defensible determination of where your property lines are and installs physical monuments you can reference going forward.
Washington-Specific Resources Summary
| Resource | URL | Best For |
|---|---|---|
| King County iMap | kingcounty.gov/services/gis/Maps | King County parcel maps and aerial imagery |
| Spokane County GIS | gis.spokanecounty.org | Spokane County parcels and assessor data |
| Pierce County Assessor | piercecountywa.gov/assessortax | Pierce County parcel and deed records |
| WA Dept. of Revenue Parcels | dor.wa.gov | Statewide parcel data across all counties |
| King County Recorder Search | recordsearch.kingcounty.gov | Recorded plats and survey documents in King County |
| WA DOL License Lookup | dol.wa.gov | Verify a PLS license before hiring |
Find a Licensed Surveyor to Confirm Your Property Lines
Online research is a starting point. A licensed PLS is the finish line. Our directory lists Washington Professional Land Surveyors by county and specialty. Search Washington surveyors to find a licensed PLS near you who can set monuments and provide a legally defensible boundary determination.