Spas with adults only

Calistoga, California

A 20-treatment hotel day spa in Santa Rosa with an indoor caldarium plunge pool, eucalyptus steam rooms, and walk-in or reserved day passes for adults 18+.

Idaho City, Idaho

A reservation-only hot springs soak in Idaho City with private tubs, a steam room and a $30 day pass, open five days a week.

Portland, Oregon

A 21-and-up day spa in Portland's Irvington neighborhood built around vinotherapy, with wine-infused baths, massages and Caudalie facials.

Spa, Liège

Thermal baths in the town of Spa, Belgium, fed by natural mineral water, with saunas, hammams and separate textile and naturist relaxation areas.

Rogaška Slatina, Savinjska

Wellness center at Grand Hotel Rogaška in Rogaška Slatina, Slovenia, with pools, saunas and fitness; day pass available by reservation.

Austin, Texas

Combined day spa and med spa in Bryker Woods, Austin, with 42 treatments spanning massage, facials, and injectables like Botox and fillers.

Rotorua, Bay of Plenty

A Rotorua day spa built around Ngāti Whakaue hot-springs traditions, centered on a seven-step geothermal Restorative Journey with lakeview thermal pools, mud

San Diego, California

A Carmel Valley day spa focused entirely on scalp care, with head-spa rituals from 60 to 120 minutes plus a beard-detox option for men.

Minneapolis, Minnesota

A St. Paul wellness studio in Macalester-Groveland offering infrared sauna, float tanks, salt therapy and cold plunge by reservation, adults-only, day-pass

Cleveland, Ohio

Tremont day spa in Cleveland focused on scalp treatments, facials and massage, with a private original location for couples.

San Francisco, California

Oakland float and sauna studio near Grand Lake with private float tanks, infrared sauna cocoons and cryotherapy, open daily 11am-8:30pm.

Ras Al Khaimah

A moderate-priced day spa in Ras Al Khaimah's Al Maireed area offering hammam, massage and exfoliation treatments, open daily 9am to 9pm.

Santa Fe, New Mexico

Hotel spa at the Eldorado in downtown Santa Fe offering massage and bodywork treatments; appointments required, no day pass.

Calistoga, California

A Calistoga day spa on Lincoln Avenue specializing in lymphatic bodywork and facial treatments, with a relaxation lounge for adults and solo travelers.

Denver, Colorado

A reservation-only massage studio in Denver's Five Points neighborhood, run by a licensed therapist with a relaxation lounge and no same-day bookings.

Park City, Utah

A Park City studio pairing private infrared sauna cabins with float therapy tanks, booked by reservation, with membership options for regulars.

San Francisco, California

Upscale day spa on Union Street in San Francisco's Cow Hollow, offering around 20 facial and massage treatments, including a signature Quadruple Lift Facial.

Brežice, Posavje

A large thermal water park in Brežice, Slovenia, with a year-round indoor pool riviera, an adults-only sauna zone, and seasonal outdoor slides.

Ojai, California

A small Ojai day spa run by one certified therapist specializing in lymphatic drainage therapy, by reservation.

Elkridge, Maryland

A halotherapy day spa in West Elkridge, near Baltimore, built around a salt cave, massage rooms and a yoga studio, aimed at solo adult visitors.

Asheville, North Carolina

A day spa in a converted barn on Horse Shoe Farm near Asheville, offering massage and body treatments amid farm and mountain surroundings.

Napa Valley, California

A single-treatment float spa in Napa offering sensory-deprivation float pods with Epsom salt water, plus dedicated parking and walk-in access.

Ojai, California

A one-room day spa in Ojai pairs skincare facials with Human Design readings, with treatments from $110 to $350 and walk-ins welcome.

New York City, New York

Thermal bath circuit and massages in a restored 1883 Tribeca textile factory, with a skylit tepidarium and candlelit thermal pools; reservation required.