Spas with reservation required

A luxury day-pass wellness circuit inside Carillon Miami Wellness Resort, with sauna, steam, cold plunge and thermal pools in North Beach.

A boutique day spa in downtown Napa Valley with nine treatment rooms offering massage, facials and body work, plus sauna, steam and a thermal pool.

Day spa in Plainfield, IN offering facials, massages and body-sculpting treatments alongside a sauna, steam room and thermal pool, reservation required.

Two Indianapolis locations for cryotherapy, infrared sauna, Normatec compression and float therapy, with walk-ins welcome.

A Brentwood day spa focused entirely on scalp and head treatments, with private suites and a signature ritual built around halo water therapy.

Day spa in South Scottsdale focused on facials and a signature holistic massage, with sauna, steam room, thermal pool and cold plunge on site.

Affordable day spa in Williamstown, NJ with sauna, steam room and thermal pool, offering massages, facials and couples treatments.

Day spa in Allisonville, Indianapolis with sauna, steam room, thermal pool and cold plunge, plus about 10 massage and facial treatments for solo visits or

North Scottsdale day spa with massage, facials, sauna, steam and a thermal pool, plus private suites for couples and groups.

A 14-room hotel spa at Westgate Park City Resort with a waterfall, sauna, steam room and thermal pools, open daily 9:30am-6:30pm.

A Houston day spa near Memorial Park offering massage, facials and spa packages, with a sauna, steam room and pool on site.

Hotel spa at the Inn at Eagle Mountain in Fountain Hills with sauna, steam room, pools and a $69 60-minute massage as its signature treatment.

Adults-only resort spa built into a wine cave in Napa, with a vineyard-view pool, sauna, steam room and hot tub; reservations required.

A West Town day spa built around a beer soak, with sauna, steam room, salt room and thermal pool for couples or solo visits.

Massage-focused day spa in Rocky River offering couples treatments, sauna, steam room and thermal pool, open daily by appointment.

An adults-only wellness retreat on Ubud's Ayung River offering multi-day healing programmes, thermal circuits and plant-based cuisine by reservation only.

Day spa in Tucson's La Encantada shopping center with a thermal circuit of sauna, steam room, cold plunge and soaking pools.

A moderate-priced day spa in Charlotte's SouthPark area with a sauna, steam room and thermal pool alongside massage, facial and body-treatment menus.

A medical spa in central Scottsdale offering 32 treatments—facials, massage, Botox, and a bridal package—alongside a sauna, steam room and thermal pool.