Spas with reservation required

Philadelphia, Pennsylvania

Hotel spa in Center City Philadelphia with a heated indoor saltwater pool, fitness center and day-pass access for non-guests.

Scottsdale, Arizona

Hotel spa inside Hotel Solaya in South Scottsdale built around Tod Miller's proprietary BodyWalking compression technique, with four treatments and a $335

Palm Springs, California

A 16-room adults-only hotel in Desert Hot Springs with three natural mineral-water pools fed by a 350-foot geothermal well, plus a small on-site spa and

Merano, Trentino-South Tyrol

An adults-only, guests-only longevity retreat and hotel spa in Merano with a medical-led wellness institute and private suite treatments.

Rogaška Slatina, Savinjska

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

Santa Fe, New Mexico

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

Park City, Utah

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

Boston, Massachusetts

Day spa in Fenway–Kenmore offering massage, facials, and waxing, with couples treatments and a monthly membership option.

Rishikesh, Uttarakhand

An upscale riverside resort 18 km outside Rishikesh with an in-house spa, yoga studio and restaurant, open only to overnight guests by reservation.

San Diego, California

A day spa in University City, San Diego, open since the late 1990s, offering facials, massage and lymphatic drainage with a monthly membership option.

New York City, New York

Adults-only day spa in Maplewood, NJ, offering deep tissue massage, bodywork and facials by appointment, open daily 9am-8pm.

Atlanta, Georgia

A Midtown Atlanta hotel day spa with massage, facials, nail services, a steam room and a lounge serving mimosas and spa bites.

Philadelphia, Pennsylvania

A second-floor day spa near Rittenhouse Square offering skincare, scalp analysis and its signature Aroma Chakra Balancing Therapy, with a membership discount

Tucson, Arizona

Day spa near Swan Way Park in Tucson with a cedar hot tub, cold plunge, infrared sauna and massage, bookable by reservation for adults only.

Key West, Florida

A hotel spa at Pier House Resort in Key West for guests only, offering couples treatments for ages 14 and up with advance reservations.

Solvang, California

A resort spa inside Alisal Ranch, a 10,500-acre luxury guest ranch in Santa Ynez Valley open only to overnight guests by reservation.

Los Angeles, California

A hotel spa at the Conrad Los Angeles in Downtown LA, open only to hotel guests by reservation, with an adults-only, couples-friendly setting.

Hudson Valley, New York

A day spa in Rhinebeck Village offering skin and wellness treatments, with VIP memberships and walk-in availability by reservation.

Kapaau, Hawaii

An oceanfront eco-boutique hotel and wellness retreat on Hawaii Island's North Kohala coast, open to overnight guests only, not day visitors.

Hudson Valley, New York

A French-inspired hotel spa in the center of Rhinebeck village, open to overnight guests by reservation.

Naples, Florida

A medical spa in Naples offering consultations, skin analysis, laser treatments and medical weight loss programs, open weekdays by appointment.

Park City, Utah

A sauna-and-cold-plunge day spa in Park City with memberships, private group buyouts, and reservation-only access.

Nashville, Tennessee

A Gulch studio for infrared sauna and cold plunge sessions in private suites, open daily with reservations required.

Carmel-by-the-Sea, California

A hotel spa inside Carmel-by-the-Sea's Hyatt Regency Monterey property, with hydrotherapy, sauna and a relaxation lounge for guests and couples.