Posey Island State Park
Its 2 sites are reservable through Washington State Parks, by phone at (360) 378-2044, camping costs Primitive and water trail sites $12/night (statewide rate), and it is open year-round. Posey Island State Park is a State Park campground near Roche Harbor, Washington.
Reservable: Washington State Parks, by phone at (360) 378-2044
1 / 2Campsite on Posey Island. Photo: Bureau of Land Management Oregon and Washington, Public domain
- Managed by
- State Park
- Hookups
- None
Posey Island State Park sits inside Posey Island State Park and San Juan Islands National Monument. Each unit's rules and boundary are on publiclandsdb.com. It sits 0.4 miles outside the boundary of San Juan Wilderness; its permit and camping rules and boundary are on publiclandsdb.com. It sits 0.4 miles outside the boundary of San Juan Islands National Wildlife Refuge; its hours, camping, hunting and fishing rules, and boundary are on publiclandsdb.com.
Getting a site
- Managed by
- State Park
- Reservations
- Washington State Parks, by phone at (360) 378-2044
- Fee
- Primitive and water trail sites $12/night (statewide rate)
- Entrance fee
- None for campers in the park they stay in; Discover Pass $10/day or $45/year for day visits
Source: parks.wa.gov, accessed 2026-09-29
Sites and hookups
- Total sites
- 2
- Hookups
- None
- ✓ Toilets
- ✓ Fire rings
- ✓ Pets allowed
- ✕ Potable water
On site: Toilets, fire rings, and pets allowed. No potable water.
Source: parks.wa.gov, accessed 2026-09-29
Rules
- Stay limit
- 10 nights in one park within a 30-day period; 90 nights per calendar year in all state parks
- Quiet hours
- 10 p.m. to 6:30 a.m.
- Pets
- Allowed
Source: parks.wa.gov, accessed 2026-09-29
Access and cell service
- Elevation
- 13 ft
Cell coverage by carrier (FCC map)
- AT&T
- 4G LTE and 5G (35/3 Mbps)
- T-Mobile
- 4G LTE and 5G (35/3 Mbps)
- Verizon
- 4G LTE; 5G mapped about 0.3 mi away
Source: FCC Broadband Data Collection, data as of December 31, 2025
Outdoor coverage each carrier reports to the FCC at this campground's map point, and the nearest mapped coverage within about half a mile. The FCC map only includes 4G LTE at 5/1 Mbps or better and 5G; a weaker signal, a text, or an emergency call may still get through, but don't count on it. These are carrier predictions, not measurements, and can be wrong either way: real service in canyons, under trees, and inside a tent or vehicle is often weaker. 5G speeds are the FCC's 7/1 and 35/3 Mbps tiers. This product uses the FCC Data API but is not endorsed or certified by the FCC.
48.6182, -123.1680 in San Juan. Open in OpenStreetMap. Map © OpenStreetMap contributors.
Season and winter services
Posey Island State Park is open year-round . In winter: water off, per the managing agency.
Sources: parks.wa.gov, accessed 2026-09-29; epqs.nationalmap.gov, accessed 2026-09-29
Common questions
Do you need a reservation at Posey Island State Park?
How much does it cost to camp at Posey Island State Park?
Is there a separate entrance fee at Posey Island State Park?
How many campsites does Posey Island State Park have?
Does Posey Island State Park have RV hookups?
Is there drinking water at Posey Island State Park?
Are dogs allowed at Posey Island State Park?
When is Posey Island State Park open?
Is Posey Island State Park open in winter?
How long can you stay at Posey Island State Park?
Is there cell service at Posey Island State Park?
Who manages Posey Island State Park?
Around Posey Island State Park
The nearest lake with a fishing page is Egg Lake, whose mapped center point is 5.3 miles away in a straight line. Stocking record and species: Egg Lake fishing on fishypedia.com.
Public land within 15 miles: Stuart Island State Park (4.4 miles to its center) , Jones Island State Park (5.5 miles to its center) , Lime Kiln Point State Park (7.1 miles to its center) , and Griffin Bay State Park (12 miles to its center) ; publiclandsdb.com has each unit's camping rules and boundary.
Hot springs nearby
The nearest hot spring to Posey Island State Park, in a straight line: Doe Bay Resort Hot Springs (hot spring, 17 miles). Each has its own page on swimholesmap.com.
First-come Stuart Island Marine State Park 
Reservable San Juan County Park Campground First-come Jones Island Marine State Park Reservable San Juan County Fairgrounds RV Camping More campgrounds: camping near Roche Harbor and campgrounds in San Juan.
Sources
- parks.wa.gov (all fields), accessed 2026-09-29
- services5.arcgis.com (coordinates), accessed 2026-09-29
- parks.wa.gov (reservationSystem), accessed 2026-09-29
- parks.wa.gov (season), accessed 2026-09-29
- parks.wa.gov (fee), accessed 2026-09-29
- parks.wa.gov (stayLimit, quietHours, generatorsAllowed, entranceFee), accessed 2026-09-29
- epqs.nationalmap.gov (elevationFt), accessed 2026-09-29
- broadbandmap.fcc.gov (cellCoverage), accessed 2026-09-27
Photo credits
- Photo 1: Bureau of Land Management Oregon and Washington, Public domain
- Photo 2: Bureau of Land Management Oregon and Washington from Portland, America, Public domain