Spas with reservation required

French Riviera, Provence-Alpes-Côte d'Azur

Hotel spa inside Nice's Le Negresco with hammam, sauna and fitness center; outside guests must book a 90-minute treatment to use the wet areas.

Macomb County, Michigan

A budget-friendly day spa in Shelby Township, MI offering facials, body sculpting and a sauna, steam room and thermal pool for adults.

Scottsdale, Arizona

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

Port Douglas, Queensland

Day spa in Port Douglas with sauna, steam room, thermal pools and cold plunge, offering massages, facials and body treatments by appointment.

Hudson Valley, New York

A Newburgh day spa built around a Japanese head spa signature treatment, with massage, sauna, steam room and pool access, open seven days a week.

Santa Fe, New Mexico

A 77-acre hot springs resort outside Santa Fe with spring-fed thermal pools, day-pass soaking packages from $175, and overnight lodging.

Saturnia, Tuscany

Walk-in thermal park in the Maremma countryside with four outdoor sulfur pools, hydromassage jets and a vascular circuit fed by a 3,000-year-old spring.

Hudson, New York

Adults-only communal thermal baths and steam room in downtown Hudson, NY, with day passes, memberships and treatment-plus-soak packages.

Rishikesh, Uttarakhand

A compact Ayurvedic spa and yoga retreat near Laxman Jhula in Rishikesh, offering six treatments including Shirodhara by appointment only.

Park City, Utah

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.

Naples, Florida

Luxury day spa in Central Naples offering massage, facials and combination packages, including a $420 signature ritual, with couples treatments by reservation.

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

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.

Boston, Massachusetts

A Seaport social wellness club in Boston offering saunas, ice baths, IV therapy, red light and HBOT sessions, with reservations required and no membership

Scottsdale, Arizona

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

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

Houston, Texas

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

Napa Valley, California

Hotel day spa atop the Archer in downtown Napa with a water deck, fitness studio access and treatment rooms; reservations required.

Saratoga Springs, New York

Historic 1935 bathhouse in Saratoga Springs offering mineral water soaks and massages in original tubs, reservation only, moderate pricing.

Budapest

A centuries-old Turkish-style thermal bath on the Buda riverside with pools, saunas, massages and weekend late-night soaking hours.

Liverpool, New York

A moderate-priced day spa in Liverpool, NY, offering 20 massage-focused treatments plus sauna, steam, cold plunge and thermal pools, open daily 10am–8pm.

Cockeysville, Maryland

A Cockeysville medical day spa blending clinical massage, sauna, steam and thermal pool with reiki, coaching and corrective exercise for chronic pain and

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.

Scottsdale, Arizona

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.