Spas with reservation required

Seattle, Washington

A private floating bathhouse on Seattle's Lake Union, booked out entirely for one group of up to 12 for sauna, cold plunge and hot tub rounds.

Austin, Texas

Medical spa and day spa on South Lamar offering facials, injectables, massage and a signature $1,499 Mermaid Lift, open daily with private rooms and a stocked

Aspen, Colorado

A downtown Aspen wellness studio offering sauna, cold plunge, IV drips, hyperbaric oxygen, red light therapy and sports massage, open daily 10am–6pm for adults.

Miami, Florida

Day spa in the Sherry Frontenac Hotel's lower lobby in Miami Beach, with sauna, steam, cold plunge and thermal pool alongside massage treatments.

Miami, Florida

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

Chicago, Illinois

Hyde Park day spa since 1978 offering facials, massage, body treatments, waxing and hydrotherapy, with walk-ins welcome.

Kuala Lumpur

An onsen-style day spa in Kampung Baru, Kuala Lumpur, with thermal pools, sauna, steam room and couples treatments.

Asheville, North Carolina

A massage-focused day spa in Asheville's Five Points offering Thai, ashiatsu and signature integrative bodywork from $130.

Berkshires, Massachusetts

A combined hair, nail and spa salon in Pittsfield offering massages, facials and a private infra-red sauna by appointment.

Napa Valley, California

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.

Washington, D.C., District of Columbia

A Northwest DC day spa on 14th Street specializing in massage, facial and skincare treatments, with walk-ins accepted but reservations recommended.

Salt Lake City, Utah

A Salt Lake City day spa in the Ballpark neighborhood combining flotation tanks with customized massage, plus a relaxation lounge for couples or solo visits.

Glenwood Springs, Colorado

A reservation-only tub house in Glenwood Springs built around Czech-style beer baths, with infrared sauna and private rooms for solo soaks or couples.

Plainfield, Indiana

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

Sacramento, California

Day spa in Sacramento's Oak Park with float rooms, private cold plunge and sauna suites, infrared sauna, and a Somadome meditation pod.

Istanbul

A working Ottoman hammam built in 1741 in Istanbul's Fatih district, offering traditional bath rituals with no day-pass option, only full treatments.

Medellín, Antioquia

Day spa in a rooftop wellness area at the Celestino Hotel in El Poblado, with sauna, steam room, jacuzzi, cold plunge and massage treatments.

Charleston, South Carolina

A West Ashley day spa in Charleston focused on scalp and hair treatments, with the $165 Signature Head Spa as its main draw.

Marrakech, Marrakesh-Safi

A 1,200-square-metre hotel spa at Selman Marrakech built around the Chenot method, with hammams, pools and multi-day wellness programmes.

Jackson Hole, Wyoming

Rooftop hotel spa at Hotel Terra in Teton Village offering facials and massages, with hot tub and steam room access included only when you book a treatment.

Hot Springs, Arkansas

A combined day spa and med spa in Hot Springs offering massages, facials, laser treatments and lunch-inclusive packages by reservation.

Hong Kong

Hotel spa on the 41st floor of the Cordis in Mong Kok, with a day pass covering pool, sauna, steam room and onsen shower for HK$500.

Los Angeles, California

A Glendale day spa offering massage, facials, waxing and nail care, plus private jacuzzi-and-sauna suites, open daily 9am to 9pm with walk-ins welcome.

Los Angeles, California

A day spa inside the Westin Bonaventure in Downtown LA, with massages, facials, body treatments, sauna and a relaxation lounge.