This blog originally appeared on hotspring.com. It has been edited for clarity and length.

What Is The Ideal Hot Tub Temperature?

When you choose a Hot Spring spa, you’re not just buying a hot tub – you’re making a long-term investment in health, vitality, and well-being. Like any fitness equipment, a hot tub provides maximum benefit with regular use. It can become an essential part of a daily routine when it’s always ready and set to the perfect temperature.

Determining the ideal temperature is key to getting the most out of a hot tub experience, but there are several variables to consider.

What Temperature Should A Hot Tub Be?

While the ideal hot tub temperature varies from person to person and depends on factors such as age, health, and personal preference, there are recommended guidelines to keep in mind.

Set Temperature At Or Below 104° F Degrees For Adults.

The U.S. Consumer Product Safety Commission states that temperatures above 104°F are dangerous for adults because they can lead to heatstroke. For a comfortable soak, most people set their hot tub between 100°F and 102°F. Healthy adults are safe to soak at these moderate temperatures for 20 minutes at a time.

Start Low, Then Gradually Raise The Spa Temperature.

Set the spa controls to 98°F or 99°F, and as you soak, increase the temperature gradually until you can enjoy an invigorating massage without feeling overheated. If you have the urge to get out or sit on the cooling step after a couple of minutes, that’s a sign that the water temperature is too high for comfort.

Consider The Preferences Of Everyone In The Tub.

When soaking with friends or family members, consider the age and health of everyone in the tub, and set a temperature appropriate for everyone in the group.

How Long Will It Take For My Spa To Warm Up When I'm Ready To Use It?

After filling the spa for the first time, allow 18 to 24 hours for the water to reach a temperature of 100°F. After an initial setup is complete and you’re enjoying daily hot tub use, you’ll want to make sure the hot tub is always ready to deliver the ultimate in hydrotherapy. To do so, simply set the spa to your ideal temperature, then close it up and leave the thermostat set at that level. Hot Spring spas feature insulated cabinets, custom-fitted covers, and energy-efficient circulation pumps that work together to maintain a steady temperature while conserving energy.

How Much Will My Utility Bill Increase?

Utility costs vary depending on model and usage, but you can be confident a Hot Spring spa is built to be energy efficient. All models are certified to the California Energy Commission (CEC) requirements. California sets the standard for energy-efficient hot tubs, so you can have peace of mind knowing that it’s designed to keep operating costs low no matter where you live.

When Should I Change My Normal Temperature Setting?

While a “set it and forget it” approach is recommended for convenience, energy efficiency, and the longevity of the spa, here are some times when you should consider dropping the water temperature by a few degrees:

When you’re exercising in your hot tub, such as doing stretches or yoga.
When the outdoor temperature is high, or if you’re overheated from exercise or illness.
If there will be others in the tub who require a lower temperature.

What Temperature Is Best For Hydrotherapy For Arthritis Relief?

A hot tub soak is good for you! The heat improves blood flow, can help improve joint flexibility, and can provide relief from arthritis pain. There are even recommended hot tub stretches and water exercises for arthritis relief. You can experience these benefits at relatively low temperatures – so set the spa at around 100°F to start, and raise it to suit your comfort level.