County · code 53055
San Juan CountyWashington
San Juan County is a county in Washington, with its seat in Friday Harbor. It was formed in 1873.
- Founded1873
- County seatFriday Harbor
- Named forSan Juan Islands, Washington State
- Land area174 sq mi + 447 sq mi water
- Population17,788 2020 Census
- Parcels mapped17,295 checked 14 October 2026
Where it is
San Juan on the map of Washington
Washington has 39 counties and county equivalents, each with its own records office. Shapes with a page are links.
History
Formed in 1873 from Whatcom County
An old deed may name a county that no longer exists, or a boundary that has since moved.
San Juan County was created by Washington Territory from Whatcom County on October 31, 1873, and was named after the San Juan Islands.
- 1873San Juan County created San Juan created by Washington Territory from Whatcom. · Wash. Terr. Laws 1873, 4th biennial sess., pp. 461-463
- 1877Boundary clarified San Juan boundary with Island redefined (no change).with Islandno change· Wash. Terr. Laws 1877, 6th biennial sess., pp. 425-426
Land and parcels
What the maps cover in San Juan
Who publishes each layer, how good it is, and when we last checked.
-
Parcels Fallback
Lot lines and tax-map numbers for 17,295 parcels. Drawn for tax purposes: usually within a few feet of a survey, but not a survey. This copy is a fallback, not the county's own: use it as a guide and check the official record.
edited 29 June 2023 · checked 14 October 2026 -
Address points Missing
No public address points layer found for San Juan County yet.
-
Buildings Reference
Roof outlines traced from aerial imagery from FEMA Response Geospatial Office with Oak Ridge National Laboratory (ORNL). Good for seeing what is on a lot; not accurate enough to set a fence from.
checked 18 October 2026
- Official
- from the office that keeps the record
- Good enough
- a reliable statewide or national copy
- Fallback
- a guide only; check the official record
- Missing
- nothing public found yet
People and land
San Juan by the Census
Source: US Census Bureau, 2020 Census; US Census Bureau, 2020 Gazetteer Files. Not endorsed or certified by the Census Bureau.
Rules and offices
Who to ask before you build, dig or sell
Official county pages only. We link to them; we do not copy them, because they change.
Inside a city or town, permits usually come from that city rather than the county.
Permits
Zoning and code
County government
- County government
The official website of San Juan County.
See your own lot on these maps
Open San Juan County on Parcel Chart's free map and click your parcel. Save it with a free account; the full record of your place (site map, projects, documents) is Pro, in early access.
Questions
Common questions about San Juan County
- When was San Juan County founded?
- San Juan County was founded in 1873, formed from Whatcom County, and named after San Juan Islands, Washington State.
- What is the county seat of San Juan County?
- The county seat of San Juan County is Friday Harbor.
- Is there an online parcel map for San Juan County?
- Yes. A public source publishes a parcel map of 17,295 parcels, rated fallback here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
- Has San Juan County's boundary or name changed?
- San Juan County was created in 1873 from Whatcom County. Its boundary has been clarified one time since, with no change on the ground.
- Who issues building permits in San Juan County?
- The county's page on building permits: Applying for a Permit. Inside a city or town, ask that city first.
- Who issues septic and well permits in San Juan County?
- The county's page on septic systems and wells: Environmental Stewardship.
- Is my lot in a flood zone?
- We do not have flood maps for San Juan County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.
Nearby