Spas with reservation required

An adults-only wellness retreat on Ubud's Ayung River offering multi-day healing programmes, thermal circuits and plant-based cuisine by reservation only.

Float Horizen is a day spa in Nashville's East End offering sensory-deprivation float tanks, infrared sauna, massage and sound meditation sessions.

All-inclusive multi-night wellness retreat in Pisgah Forest, NC, combining fitness classes, spa treatments, guided hikes and farm-to-table meals in private

A full-service salon and spa in Orlando pairing hair, skincare and waxing services with a monthly membership plan for mix-and-match treatments.

A moderate-priced day spa in Charlotte's SouthPark area with a sauna, steam room and thermal pool alongside massage, facial and body-treatment menus.

A reservation-only day spa on El Camino Real in San Bruno specializing in head spa therapy, scalp care and lash services for adults.

A moderate-priced day spa in Des Peres, just west of St. Louis, open six days a week with a relaxation lounge and treatments geared toward couples and adults.

A San Mateo day spa with a hot tub, open daily 10am-9pm, taking both walk-ins and reservations for couples or solo visits.

A medical spa on San Antonio's Far West Side offering massage, facials, injectables and laser hair removal, open weekdays and Saturday mornings.

Day spa in a Montebello strip mall plaza offering facials, massages and body treatments, open daily with walk-ins accepted.