Montana has couple of nudist resorts. The list below should not be considered complete, though we've made our best efforts to list all of the ones we know of:
Boise
Bare Backers
PO Box 5781
Boise, ID 83705
208-322-6853
www.bareidaho.com
Worley
Sun Meadow Resort
30400 Sunray Trail
Worley, ID 83876
208-686-8686
www.sunmeadow.org