Spas with reservation required

Bishop, California

A century-old natural hot springs pool near Bishop in the Eastern Sierra, with a cooling waterfall, a separate hot soak, and simple day-use facilities.

Miami, Florida

Nature-themed day spa in Brickell with hydro massage, a hydrotherapy circuit and couples treatments, open daily 9am-6pm.

Philadelphia, Pennsylvania

Northeast Philadelphia day spa on Castor Avenue focused on skin treatments, massage and Venus Legacy body contouring, with sauna, steam and a thermal pool.

Phuket

Adults-only Ayurvedic resort on a Rawai hillside with doctor-led Panchakarma programs, a saltwater pool and 47 private villas.

Indianapolis, Indiana

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

Austin, Texas

Hotel spa at Omni Barton Creek with steam room, sauna, cold plunge and a rooftop pool overlooking Hill Country, open daily 9am-7pm.

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.

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.

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.

Denver, Colorado

A Whittier day spa in Denver where private suites pair beer and wine baths with infrared saunas and a self-pour taproom.

Denver, Colorado

A Littleton day spa centered on private suites with beer and wine baths, infrared sauna, zero-gravity massage and a self-pour taproom.

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.

Austin, Texas

Eco-friendly day spa in Anderson Mill, Austin, offering organic massage, facials and body treatments with a sauna, steam room and cold plunge.

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.

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

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

Cincinnati, Ohio

Day spa in Columbia-Tusculum, Cincinnati, with massage, facials, an infrared/Himalayan salt sauna and a $99 signature sampler package.

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.

Philadelphia, Pennsylvania

A Center City West day spa and salon on the Avenue of the Arts with two therapy suites that pair infrared heat or red light with salt air.