Spas with sauna

A vacation-rental resort in Ramona whose day-spa access, sauna, steam room and heated pool are reserved for guests staying on the property.

A hillside boutique hotel spa outside Sayulita with sauna, steam room, cold plunge and ocean-view pool, open on a day-pass basis.

An all-inclusive beachfront resort spa in Huatulco with a sauna, steam room and thermal pools, open only to hotel guests.

A 25-room Sonoma hotel in Forestville with a spa barn offering sauna, steam and pools, mainly for overnight guests.

Hotel spa on Shelter Island in San Diego with sauna, steam room, and pool, open to guests staying at Kona Kai Resort.

A hotel spa on Mission Bay in San Diego with sauna, steam room, cold plunge and thermal pools, open only to resort guests.

A hotel spa inside the Four Seasons Resort Chiang Mai in Mae Rim, with sauna, steam room, cold plunge and thermal pools set among rice paddies, open to resort

A hotel spa at the 65-acre Fairmont Scottsdale Princess resort in North Scottsdale, open to overnight guests with sauna, steam room and pool access.