Spas with reservation required in California

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.

Palm Springs, California

Moroccan-themed inn in Desert Hot Springs with natural mineral hot springs, a spring-fed pool and day-pass access from 9am to 4pm.

Palm Springs, California

Hotel spa inside the Avalon in Palm Springs, open Thursday through Monday, with a $75 day pass covering jacuzzi, sauna, cold plunge and steam rooms.

Napa Valley, California

Hotel day spa atop the Archer in downtown Napa with a water deck, fitness studio access and treatment rooms; reservations required.

Carmel-by-the-Sea, California

Upscale day spa in Carmel-by-the-Sea's Golden Rectangle with sauna, steam, cold plunge and thermal pools, open daily from 6:30am.

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

Adults-only hotel spa at Tommy Bahama Miramonte in Indian Wells with 15 treatments, eucalyptus steam rooms, a hydrotherapy jacuzzi and saltwater pool.

Napa Valley, California

Adults-only resort spa built into a wine cave in Napa, with a vineyard-view pool, sauna, steam room and hot tub; reservations required.

San Diego, California

Hotel spa at the historic Hotel del Coronado with an ocean-view pool, 20 treatments, and a seaweed-based signature Ocean Essence Ritual.

Palm Springs, California

Hotel spa at Agua Caliente Rancho Mirage with day passes for the sauna, steam room, salt rooms and private spa pool.

Lake Tahoe, California

A South Lake Tahoe day spa built around Japanese cedar enzyme detox baths, with a lake-view relaxation lounge and couples sessions by reservation only.

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.

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.

San Diego, California

Adults-only hotel spa in Carmel Valley with a hydrotherapy circuit, two fireplace lounges, and a $100 day pass covering pools and fitness facilities.

San Diego, California

Resort spa on Mission Bay offering massages, facials and body treatments, with walk-ins welcome and a gym and yoga classes on-site.

Calistoga, California

A 20-treatment hotel day spa in Santa Rosa with an indoor caldarium plunge pool, eucalyptus steam rooms, and walk-in or reserved day passes for adults 18+.

Los Angeles, California

Day spa in Woodland Hills with a hydrotherapy circuit, massage, facial and body treatment menu, open daily 8am-10pm (closed Tuesdays).

Palm Springs, California

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

Los Angeles, California

A day spa on La Brea Avenue near the Fairfax area of Los Angeles offering massages, facials and hydrotherapy, with reservations recommended.

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.

Calistoga, California

MoonAcre Spa & Baths is a day spa in Calistoga with a thermal pool, hot tub and sauna, open daily 9am–5pm and geared toward families and couples.

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.

San Francisco, California

A moderately priced fitness-club spa in downtown San Francisco offering bodywork, skincare and specialty treatments with reservations required.