Post Street Ale House
1 N Post Street, Spokane, WA
100% positive
Directions: Towards the back, past the hostess station and kitchen, on the west wall.
Comments: Not sure if they allow them as walk-in friendly "public restrooms" but it's a busy restaurant/bar so it would be pretty easy to get in and out quickly. They are quite large, separate room/single stall, locking unisex bathrooms.