Spas with upscale

San Francisco, California

Adults-only hotel spa in Sausalito, California, offering day passes alongside yoga and a restaurant on site.

Encinitas, California

Adults-only day spa in Leucadia, Encinitas, about a mile from the beach, with private suites, a relaxation lounge and movement classes.

Riviera Maya, Quintana Roo

Beachfront all-inclusive resort in Playa del Carmen with a hydrothermal circuit spa available to hotel guests for an extra charge.

Biarritz, Nouvelle-Aquitaine

Nuxe-branded hotel spa inside the Grand Tonic in Biarritz, open to hotel guests for treatments, a relaxation lounge and private suites.

Cancún, Quintana Roo

A boutique hotel near Cancún airport with a small wellness wing — pool, jacuzzi, sauna, steam room and temazcal — open to day-pass visitors.

Opatija, Primorje-Gorski Kotar

Hotel spa inside Opatija's Hotel Miramar, open only to guests staying in its 108 mostly sea-view rooms.

Riviera Maya, Quintana Roo

A resort spa inside the Iberostar Waves Tucán in Playacar offering sauna, Turkish bath and jet-pool treatments, open to day-pass visitors 16 and up.

Jekyll Island, Georgia

Hotel spa at Jekyll Island Club Resort offers outdoor baths and a pool with ocean views, open only to resort guests.

Tulum, Quintana Roo

A boutique hotel resort in Tulum's Aldea Zama with two pools, a yoga terrace and a rooftop restaurant, open to overnight guests rather than day visitors.

San Juan

Adults-only hotel spa inside La Concha Resort in Condado, San Juan, offering couples massages and a small treatment menu for guests 18 and up.

Riviera Maya, Quintana Roo

Beachfront resort spa in Playa del Carmen built around Mayan wellness themes, open to hotel guests only, with yoga sessions and a relaxation lounge.

Mumbai, Maharashtra

An Ayurveda-based day spa on Marine Drive in Mumbai offering massage, detox and beauty therapies with a relaxation lounge and yoga space.

Aspen, Colorado

O2 Aspen is a day spa on South Mill Street offering facials, a yoga studio and a retail boutique, open daily with walk-ins welcome.

Half Moon Bay, California

A full-service spa inside an oceanfront hotel at Half Moon Bay Harbor, offering massages, facials and body treatments to guests by reservation.

Las Vegas, Nevada

Hotel spa inside Caesars Palace in Las Vegas with a hydrotherapy circuit and relaxation lounge, open daily 9am–6pm for hotel guests.

Aachen, North Rhine-Westphalia

Adults-only day spa in Aachen with a hydrotherapy circuit and relaxation lounge, open daily 10am–9pm, upscale pricing.

Goa

A hotel spa inside Sea Queen Beach Resort on Colva Beach, Betalbatim, Goa, open to overnight guests with one signature treatment called The Sea View.

Aachen, North Rhine-Westphalia

A suite hotel in central Aachen where each private room has its own jacuzzi and sauna, booked by the night rather than a day pass.

Dallas, Texas

Hotel spa inside The Highland Dallas in Lower Greenville, Dallas, with a sauna, steam room, outdoor pool and couples treatment rooms.

Sedona, Arizona

Hotel-only spa amenities at The Joy Sedona, a B&B and creekside cabin property near Uptown Sedona with outdoor hot tubs, a relaxation lounge and private suites.

Lake Tahoe, California

Hotel-only spa at a lakefront resort in South Lake Tahoe, with an outdoor heated pool, Jacuzzi and treatment rooms aimed at couples.

Las Vegas, Nevada

A 17,000-square-foot hotel spa in Las Vegas with 15 treatment rooms, a fitness center and a yoga studio, open to Palms guests daily.

Carmel-by-the-Sea, California

A hotel spa at Sanctuary Beach Resort in Marina, with three treatment rooms, a relaxation lounge and an outdoor deck looking over the dunes and Pacific.

Napa Valley, California

Adults-only resort spa in Napa Valley with pools, sauna, steam and a fitness center, open to hotel guests and club members via day pass.