Spas with private suites

Daylesford, Victoria

A rammed-earth house on 80 hectares near Daylesford, rented whole for up to 10 adults, with in-room massage and a two-night minimum stay.

Palm Springs, California

Adults-only hot springs resort on Miracle Hill in Desert Hot Springs with private mineral tubs, a Finnish sauna, salt room and 35 spa treatments.

Durango, Colorado

A hot springs resort in the Animas Valley near Durango, Colorado, with 32 mineral pools, cold plunges, a lap pool and private cedar soaking tubs.

Seattle, Washington

A Bellevue day spa in Wilburton specializing in head spa scalp treatments, massage, facials and couples sessions, with free on-site parking.

Austin, Texas

Adults-only hotel spa at the Fairmont Austin with nine treatment rooms, a hydrotherapy circuit, sauna and cold plunge, open daily with day passes available.

Carmel-by-the-Sea, California

Resort spa at Carmel Valley Ranch with 12 treatment rooms, private terraces, a saltwater pool and infinity hot tub, open to adults by reservation.

Palm Springs, California

Hotel spa at the Renaissance Esmeralda in Indian Wells offering desert-inspired treatments, a recovery lounge, steam rooms and day passes, adults only.

Bad Wörishofen, Bavaria

Adults-only thermal baths in Bad Wörishofen with palm-house pools, mineral pools and saunas; day passes available, minimum age 16.

Lake Tahoe, California

A 17-room, adults-only hotel spa at Lake Tahoe's Ritz-Carlton with a heated lap pool, sauna and steam room; day pass access requires booking a treatment.

Portland, Oregon

Adults-only hotel spa in downtown Portland with a $50 day pass, infinity pool, sauna, steam room and cold plunge shower, booked in advance only.

Santa Ynez, California

Adults-only resort spa inside Chumash Casino Resort in Santa Ynez with 21 treatments, a mineral pool, cold plunge and couple's suites.

Napa Valley, California

Adults-only hotel spa in Napa Valley with a co-ed thermal circuit of sauna, steam room and cold shower, open daily 10am–6pm; day passes available.

Idaho City, Idaho

A reservation-only hot springs soak in Idaho City with private tubs, a steam room and a $30 day pass, open five days a week.

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.

Scottsdale, Arizona

Adults-only hotel spa at the Fairmont Scottsdale Princess with a rooftop pool, grotto waterfall pool, sauna, steam room and cold plunge, open daily 6am-7pm.

New York City, New York

A five-treatment-room hotel spa inside The Greenwich Hotel in Tribeca, built around a heated pool and Japanese-influenced design.

Palm Springs, California

Downtown Palm Springs day spa built around a natural hot mineral spring, with private mineral baths, sauna, steam room and massage.

Asheville, North Carolina

Ayurvedic destination retreat in the Blue Ridge Mountains near Asheville, with day-pass spa visits and multi-night panchakarma cleanses by reservation.

Encinitas, California

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

Big Sur, California

Adults-only hotel spa at Ventana Big Sur with ocean-view treatment rooms, outdoor cabanas for couples, and a 24-hour fitness and yoga space.