SweatHouz South Boston

467 W Broadway, Boston, MA

SweatHouz South Boston (the signage says SWTHZ) is a private contrast-therapy studio on West Broadway, a few blocks from the Broadway Red Line stop and the Day Boulevard beaches. There is no communal sauna here: you get a locked suite for 60 minutes with your own full-spectrum infrared cabin, a cold plunge tub and a vitamin C-infused rainfall shower, plus a TV, your own music or a meditation track, and a stack of towels. Staff leave a welcome card with your name in the suite, the sauna runs around 140°F and can be turned up toward 175°F from the panel, and the plunge sits near 48-55°F; the house suggestion is up to 45 minutes of heat, a rinse, then three to five minutes in the cold. It is built for people who want recovery on a schedule rather than a social scene: marathoners, early risers (doors open at 6 a.m. every day), couples, and anyone who would rather not share a bench. A first visit is $50, a Double Dose of two intro sessions is $59, and a regular drop-in is $90; packs run $169 for three, $259 for five, $449 for ten and $799 for twenty, usable at any SweatHouz, and memberships go from Launch at $99 a month for two sessions through Reset ($169, four), Elevate ($269, eight) to Unlimited at $349 with four guest passes. A second person can share your suite for an added guest fee. Wear what you like in the sauna and a swimsuit or spandex for the plunge; shampoo, conditioner and body wash are in the suite. Guests must be 18 unless accompanied by an adult, and you book a start time in the SWTHZ app or online. SweatHouz is a national chain that opened its first Massachusetts studio at Assembly Row and added this Southie location in 2023; a Fenway studio is planned for early 2027.

Quick facts

Type
Boutique Studio
Heat
Infrared sauna
Cold
Cold plunge tub
Temperatures
Infrared sauna 140–175°F; Cold plunge 48–55°F
Drop-in price
$90 per session
Membership
$349/mo unlimited
Booking
Reservation required
Session style
Appointment-based
Gender
Co-ed
Clothing
Clothing optional
Age policy
18+

Hours

Book on the facility's site

Last updated November 2026.

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