Spas with reservation required in United States

San Francisco, California

Adults-only Russian bathhouse in San Francisco's India Basin with steam rooms, cold plunge, rooftop deck and a café, open daily except Tuesday.

Las Vegas, Nevada

Adults-only hotel spa at Resorts World Las Vegas with a six-pool hydrotherapy circuit, salt room, and a themed Aufguss sauna show on weekends.

Palm Springs, California

Adults-only hot springs resort on Miracle Hill in Desert Hot Springs with private mineral tubs, a Finnish sauna, salt room and 35 spa treatments.

Hot Springs, Arkansas

A combined day spa and med spa in Hot Springs offering massages, facials, laser treatments and lunch-inclusive packages by reservation.

Miami, Florida

Hotel spa inside Dua Miami, Autograph Collection in Brickell, open daily 9am-6pm, with sauna, steam room, cold plunge and couples massage rooms.

Durango, Colorado

A hot springs resort in the Animas Valley near Durango, Colorado, with 32 mineral pools, cold plunges, a lap pool and private cedar soaking tubs.

Palm Springs, California

Hotel spa inside the Avalon in Palm Springs, open Thursday through Monday, with a $75 day pass covering jacuzzi, sauna, cold plunge and steam rooms.

New York City, New York

Hotel spa inside Thompson Central Park combining massages, facials and body treatments with daily fitness classes and private saunas, near Central Park.

Los Angeles, California

A women-focused Korean day spa in Pico-Union with steam, salt and ice rooms, open daily 9am to 9pm, with massage and facials open to men too.

Chicago, Illinois

Hotel spa on the lower level of the Fairmont Chicago, open to guests for massages, facials and a couples suite with an infinity-edge soaking tub.

San Francisco, California

Hotel spa at The Huntington Hotel on Nob Hill with a heated soaking pool, sauna, steam room and terrace, open daily 8am-7pm; treatment booking required.

Aspen, Colorado

Adults-only hotel spa at The St. Regis Aspen with Thai-inspired massage, 111Skin facials, an AI robotic massage, and a day pass covering pool, cold plunge, and

Scottsdale, Arizona

Recovery-focused studio in South Scottsdale centered on a cold plunge, hot tub, infrared sauna, compression therapy and red light rooms rather than traditional

Denver, Colorado

A 14,000-square-foot hotel spa inside Gaylord Rockies in Aurora, offering massages, facials, body treatments and a couples room, adults only.

Nashville, Tennessee

Day spa and medical spa on the third floor of The Westin Nashville downtown, with nine treatment rooms, a dry cedar sauna, steam showers and walk-in access to

Milford, Ohio

A small, adults-only day spa in Historic Old Milford with a salt room, massage room and red light therapy, booked by reservation.

Santa Fe, New Mexico

A small Santa Fe day spa centered on a halotherapy salt room, with sauna and ionic foot detox add-ons, booked by reservation only.

Las Vegas, Nevada

Adults-only hotel spa inside Westgate Las Vegas offering massages, facials, salon services, sauna, steam room and a thermal pool, open daily 9am-6pm.

Sierraville, California

A non-profit hot springs retreat near Lake Tahoe with natural spring pools, reservation-only day and evening soaks, camping and rooms, closed Mondays and

Carmel-by-the-Sea, California

Resort spa at Carmel Valley Ranch with 12 treatment rooms, private terraces, a saltwater pool and infinity hot tub, open to adults by reservation.

San Diego, California

Adults-only day spa at Mission Bay Resort with massage, facials, Himalayan salt treatments and couples suites; walk-ins and day passes welcome.

Palm Springs, California

Hotel spa at the Renaissance Esmeralda in Indian Wells offering desert-inspired treatments, a recovery lounge, steam rooms and day passes, adults only.

Palm Springs, California

Adults-only hotel spa at Tommy Bahama Miramonte in Indian Wells with 15 treatments, eucalyptus steam rooms, a hydrotherapy jacuzzi and saltwater pool.

Calistoga, California

Spa Talisa is the adults-only spa at the Four Seasons Resort Napa Valley in Calistoga, with vineyard-view gardens, barrel saunas and a sunken whirlpool for