Washington State's Islands: Count and Notable Examples

Washington State contains over 3,500 islands—one of the highest counts of any U.S. state—scattered across Puget Sound, the San Juan archipelago, and the Columbia River estuary.

Major Island Groups

San Juan Islands (172 named islands)

• San Juan Island: Largest population (~7,000), Friday Harbor (county seat)
• Orcas Island: Largest by area (57 sq mi), Moran State Park, Mount Constitution
• Lopez Island: Flattest, agricultural, cycling destination
• Shaw, Decatur, Blakely, Waldron: Smaller, less developed

Puget Sound Islands

• Whidbey Island: Largest in Washington (168 sq mi), ~70,000 residents, NAS Whidbey Island
• Bainbridge Island: 23,000 residents, 35-min ferry to Seattle
• Vashon/Maury: 11,000 residents, rural character, no bridge access
• Anderson, McNeil, Ketron, Fox, Hartstene: South Sound islands

Columbia River Islands

• Numerous small islands in estuary and reservoirs (Lake Roosevelt, etc.)
• Some tribal, some wildlife refuges, some privately owned

Ecological and Cultural Significance

• Orca habitat: Southern Resident killer whales forage San Juan channels
• Bird migration: Critical Pacific Flyway stopover
• Tribal lands: Lummi, Swinomish, Tulalip, Suquamish reservations on islands
• Ferry system: WSDOT operates largest U.S. ferry fleet serving island communities

Island County vs. San Juan County

Island County (Whidbey + Camano) and San Juan County (San Juan archipelago) are Washington's only all-island counties—unique governance challenges.