A boutique day spa in downtown Sonoma centered on infrared sauna and cold plunge drop-ins, plus massage, red light and PEMF therapy.
At a glance
- Price
- $$$
- Day pass
- $225
- Hotel guests only
- No
- Adults only
- No
- Walk-ins
- Yes
- Access
- Day passWalk-ins welcome
- Amenities
- Cold plungeSauna
- Good for
- Adults onlySolo travelers
- Price
- Upscale
Sonoma Sauna & Plunge is a boutique day spa tucked inside the Studio M Pilates & Body building on West Napa Street in downtown Sonoma. The space is built around contrast therapy — an extra-large infrared sauna paired with a cold plunge — along with red light therapy, a PEMF mat, cold laser treatment and massage. It's open to walk-ins and isn't restricted to hotel guests or adults only.
Drop-in sessions are the simplest way in: $40 gets a 30-minute infrared sauna and cold plunge session with red light therapy added, or $80 for a 60-minute version. For sauna alone, a 30-minute solo session runs $35 and 60 minutes is $70. The full day pass, at $225, bundles a 60-minute sauna/cold plunge/red light session with a 60-minute massage; a $250 upgrade swaps in a 90-minute massage instead.
Massage is also available on its own, at $155 for 60 minutes and $199 for 90 minutes, though reservation requests need to be made 24 hours ahead. Locals can join one of several monthly membership tiers — covering either infrared sauna alone or the full contrast therapy combo — with eight or twelve 30-minute sessions a month, running on an auto-pay, cancel-anytime structure.
Hours run Monday through Thursday 9am to 4pm, Friday 9am to 3pm, and Saturday 9am to 2pm; the spa is closed Sundays.
Good to know
- Do I need to book ahead or can I just walk in?
- Walk-ins are welcome for sauna, cold plunge and red light sessions; massage appointments need to be requested at least 24 hours in advance.
- How much does a day pass cost?
- The standard day pass is $225 and includes a 60-minute infrared sauna/cold plunge session with red light therapy plus a 60-minute massage; a $250 upgrade adds a 90-minute massage instead.
- Is there a cheaper way to try the sauna and cold plunge?
- Yes — drop-in sessions start at $40 for 30 minutes of sauna, cold plunge and red light therapy, or $80 for 60 minutes; sauna-only drop-ins are $35 for 30 minutes.
- Is the spa adults-only or clothing-optional?
- No, it's open to all ages and is not clothing-optional.
- What are the hours?
- Monday through Thursday 9am–4pm, Friday 9am–3pm, Saturday 9am–2pm; closed Sundays.
Details checked October 1, 2026. Prices and hours change; confirm before you go.
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