| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Suburban Villa Mobile Home Park | city | Washington | United States | 47.50 | -122.36 | 305 | |
| Sudbury | city | Washington | United States | 46.09 | -118.48 | 830 | |
| Sudden Valley | city | Washington | United States | 48.72 | -122.35 | 830 | |
| Sulphur | city | Washington | United States | 46.64 | -118.73 | 1053 | |
| Sultan | city | Washington | United States | 47.86 | -121.82 | 200 | |
| Sumas | city | Washington | United States | 49.00 | -122.26 | 49 | |
| Summer Villa Estates Mobile Home Park | city | Washington | United States | 47.21 | -122.22 | 193 | |
| Summerhurst | city | Washington | United States | 47.35 | -122.45 | 0 | |
| Summerville Estates Mobile Home Park | city | Washington | United States | 47.21 | -122.22 | 193 | |
| Summit | city | Washington | United States | 47.36 | -122.02 | 830 | |
| Summit | city | Washington | United States | 47.16 | -122.36 | 390 | |
| Summitview | city | Washington | United States | 46.60 | -120.64 | 1669 | |
| Sumner | city | Washington | United States | 47.20 | -122.24 | 164 | |
| Sunbeach | city | Washington | United States | 47.42 | -122.90 | 3 | |
| Sundale | city | Washington | United States | 45.72 | -120.32 | 400 | |
| Sunlight Beach | city | Washington | United States | 47.99 | -122.48 | 0 | |
| Sunny Hill | city | Washington | United States | 47.41 | -120.25 | 1092 | |
| Sunny Shore Acres | city | Washington | United States | 48.11 | -122.41 | 200 | |
| Sunny Shores | city | Washington | United States | 48.11 | -122.35 | 0 | |
| Sunnybank | city | Washington | United States | 47.86 | -120.15 | 1669 | |
| Sunnydale | city | Washington | United States | 47.46 | -122.33 | 298 | |
| Sunnydale | city | Washington | United States | 46.83 | -122.93 | 295 | |
| Sunnydale Mobile Home Park | city | Washington | United States | 47.48 | -122.17 | 298 | |
| Sunnyside | city | Washington | United States | 46.32 | -120.01 | 830 | |
| Sunnyside | city | Washington | United States | 48.73 | -122.32 | 341 | |
| Sunnyside | city | Washington | United States | 45.64 | -122.37 | 396 | |
| Sunnyside Mobile Court | city | Washington | United States | 48.08 | -123.11 | 269 | |
| Sunnyside Mobile Home Park | city | Washington | United States | 47.18 | -122.40 | 305 | |
| Sunnyslope | city | Washington | United States | 47.50 | -122.73 | 830 | |
| Sunnyslope | city | Washington | United States | 47.47 | -120.34 | 830 | |
| Sunrise | city | Washington | United States | 46.91 | -121.64 | 6128 | |
| Sunrise Beach | city | Washington | United States | 47.09 | -122.99 | 101 | |
| Sunrise Beach | city | Washington | United States | 47.32 | -122.70 | 3 | |
| Sunrise Manor Mobile Home Park | city | Washington | United States | 47.15 | -122.50 | 308 | |
| Sunrise Terrace Mobile Home Court | city | Washington | United States | 47.20 | -122.53 | 200 | |
| Sunset | city | Washington | United States | 48.55 | -122.41 | 9 | |
| Sunset | city | Washington | United States | 47.12 | -117.49 | 2509 | |
| Sunset Beach | city | Washington | United States | 47.09 | -122.96 | 101 | |
| Sunset Beach | city | Washington | United States | 48.21 | -122.53 | 200 | |
| Sunset Beach | city | Washington | United States | 47.23 | -124.21 | 39 | |
| Sunset Beach | city | Washington | United States | 47.22 | -122.57 | 200 | |
| Sunset Beach | city | Washington | United States | 47.41 | -122.89 | 111 | |
| Sunset Farm | city | Washington | United States | 47.66 | -122.75 | 255 | |
| Sunset Hill | city | Washington | United States | 47.68 | -122.40 | 78 | |
| Sunset Terrace | city | Washington | United States | 48.22 | -122.67 | 200 | |
| Sunset Terrace Mobile Home Park | city | Washington | United States | 47.06 | -122.31 | 830 | |
| Sunset Village | city | Washington | United States | 47.58 | -122.14 | 295 | |
| Sunshine | city | Washington | United States | 46.72 | -117.10 | 2700 | |
| Sunshine Beach | city | Washington | United States | 47.35 | -122.73 | 98 | |
| Supplee | city | Washington | United States | 47.65 | -119.88 | 2509 | |
| Suquamish | city | Washington | United States | 47.73 | -122.55 | 0 | |
| Surprise Valley | city | Washington | United States | 46.93 | -122.23 | 830 | |
| Susie | city | Washington | United States | 46.59 | -119.62 | 830 | |
| Sutico | city | Washington | United States | 46.63 | -123.53 | 400 | |
| Sutton | city | Washington | United States | 46.90 | -117.84 | 1669 |