Spas with reservation required

Austin, Texas

Adults-only hotel spa at the Fairmont Austin with nine treatment rooms, a hydrotherapy circuit, sauna and cold plunge, open daily with day passes available.

Dallas, Texas

Hotel spa inside The Adolphus in downtown Dallas, with six treatment rooms, a couple's suite and a 22-item menu of massages, facials and body treatments.

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.

Boca Raton, Florida

Hotel spa at The Boca Raton with 44 treatment rooms, a spa pool and waterfall whirlpools, open to resort guests, club members and day-pass visitors by

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

Austin, Texas

Hotel spa at Hotel Viata in West Lake Hills with treatment rooms, a couples suite, pool, sauna, steam room and a day-pass option for amenity access.

Orlando, Florida

Upscale day spa at Bella Collina private club near Orlando, open Tuesday–Sunday by appointment, with massages, facials and couples suites.

Seattle, Washington

Hotel spa inside the Hyatt Regency Lake Washington in Renton, offering massages, facials and body treatments alongside pool, hot tub and steam room access.

Austin, Texas

A fifth-floor hotel spa inside JW Marriott Austin with eight treatments, a heated rooftop pool and a 16-plus minimum age.

Jackson Hole, Wyoming

Resort spa at Teton Village with pools, soaking tubs, a rooftop hot tub, and facials built for Jackson Hole's dry alpine air.

Las Vegas, Nevada

A day spa inside Tuscany Suites & Casino in Las Vegas offering massage, facials and body treatments alongside sauna, steam and cold plunge access.

Palm Beach, Florida

A Palm Beach Gardens studio offering 60-minute private-suite sessions combining infrared sauna, cold plunge and vitamin-c shower.

Charleston, South Carolina

Private contrast-therapy suites with infrared sauna, cold plunge and vitamin C shower in West Ashley, Charleston, by reservation.

Bad Wörishofen, Bavaria

Adults-only thermal baths in Bad Wörishofen with palm-house pools, mineral pools and saunas; day passes available, minimum age 16.

Philadelphia, Pennsylvania

Day spa in Cherry Hill Township near Philadelphia offering massage, head spa scalp treatments and couples sessions, open daily 9:30am to 9:30pm.

Chianciano Terme, Tuscany

Thermal day spa in Chianciano Terme offering day passes, couples massages and a wellness-food menu, closed Thursdays and Wednesdays.

London, England

A Russian-style banya bathhouse in Belgravia offering oak-lined steam rooms, cold plunge pools and leaf-massage rituals, with day passes by reservation only.

Miami, Florida

A 12,000-square-foot hotel spa at Coral Gables' Biltmore, with eucalyptus steam rooms, Himalayan salt saunas and a couples suite; adults-only, reservation

Jackson Hole, Wyoming

Hotel spa inside the Rusty Parrot Lodge in downtown Jackson Hole offering massage, facials and couples treatments with hot tub access, day passes welcome.

New York City, New York

An Upper East Side day spa built around couples' treatments—massage, sauna and a signature rose-petal bath—by reservation only.

Portland, Oregon

An 18-and-up, clothing-optional spa in Portland's Kerns neighborhood with a salt hot tub, sauna, steam room and cold plunge, reservation required.

Atlanta, Georgia

A medical spa in Atlanta's Five Points district offering walk-in treatments, a private lounge, refreshments and luggage storage.