One of the most common questions before buying a sauna is what it will actually cost to run. The short answer: less than you might expect. A typical 90-minute session costs less than a dollar in electricity for most models, and even daily use adds only a modest amount to a monthly energy bill.

Estimated Cost Per Session

The table below shows the maximum power draw for each model (not including the red light add-on), energy consumption over a 90-minute session, and estimated cost using the US average electricity rate of approximately $0.16 per kWh.

Note: These figures represent maximum draw — real-world consumption is typically lower. Once the sauna reaches its set temperature, the heaters cycle on and off to maintain it rather than running continuously, so actual energy use per session is usually 15–25% less than the maximum figures above. Your actual cost will vary based on your local electricity rate. Check your utility bill for your per-kWh rate and multiply by the kWh/session figure above for a precise number.

Monthly Cost Estimates

Based on the per-session estimates above, here’s what regular use looks like over a month:

• 3-Person: ~$17/month at 4–5 sessions per week — ~$25/month at daily use
• 2-Person 240V: ~$14/month at 4–5 sessions per week — ~$20/month at daily use
• 2-Person 120V: ~$8/month at 4–5 sessions per week — ~$12/month at daily use

Tips for Keeping Costs Down

• Close the vents during heat-up. Open vents let warm air escape, making the heaters work longer to reach temperature and consuming more energy before your session even starts.
• Pre-schedule sessions with the app. Using the Plunge app to start a preheat cycle means the sauna is at temperature exactly when you want it — no energy wasted on idling.
• Don’t leave it running unattended. The sauna has a 90-minute auto-shutoff, but if you extend the timer, make sure someone is using it.

Tip: If your sauna is in an uninsulated space like a garage, it will work harder to reach and hold temperature, especially in cold weather. This can meaningfully increase energy use. A climate-controlled room is more efficient.