Many hot tub owners wonder whether they should turn the temperature down between soaks to save electricity.

The answer depends on how often you use your spa, the weather, and how long you’ll be away.

For most people, leaving the water at your normal temperature is actually the best choice. Modern hot tubs are designed to maintain temperature efficiently, and reheating a cooled spa takes time.

This guide explains the best temperature settings for different situations and how lowering the temperature affects operating costs.

Quick Answer

Here are some general recommendations:

Situation	Recommended Temperature
Daily use	100–104°F (38–40°C)
Used several times per week	98–100°F (37–38°C)
Away for several days	90–95°F (32–35°C)
Vacation (1–2 weeks or longer)	80–90°F (27–32°C) or use Vacation/Economy Mode if available

Every spa is different, so always stay within your manufacturer’s recommended operating range.

Does Lowering the Temperature Save Electricity?

Yes—but usually not as much as people expect.

A well-insulated hot tub loses heat slowly, especially with a quality cover installed. Because of this, maintaining temperature often uses less electricity than many owners assume.

If you use your spa every day or every few days, lowering the temperature between uses may only provide modest savings while making the spa less convenient.

The longer the spa sits unused, however, the more sense it makes to reduce the temperature.

Best Temperature Based on How Often You Use Your Hot Tub

Every Day

If you use your spa almost every day, keep it at your preferred soaking temperature—typically between 100°F and 104°F.

The water will always be ready, and the heater only needs to replace the heat that naturally escapes.

A Few Times Per Week

If you typically use the spa two or three times per week, lowering the temperature slightly to 98–100°F can reduce energy use without creating long reheating times.

Many owners find this is a good balance between convenience and efficiency.

Only on Weekends

If your spa sits unused for several days, lowering it to around 90–95°F may save more electricity.

Just remember you’ll need to raise the temperature several hours before you plan to use it.

Going Away on Vacation

If you’ll be gone for more than a week, lowering the temperature to 80–90°F or using your spa’s Vacation Mode (if equipped) is usually the best choice.

Do not turn the spa completely off unless you’re properly winterizing it.

The pumps still need to circulate water, and in colder climates shutting the spa off can allow the plumbing to freeze.

How Long Does It Take a Hot Tub to Heat Back Up?

One thing many owners forget is that lowering the temperature also means waiting for the spa to recover.

Most hot tubs heat at approximately:

3–6°F (1.5–3°C) per hour for 240-volt models
1–2°F (0.5–1°C) per hour for many 120-volt plug-and-play models

For example:

Temperature Change	Approximate Recovery Time (240V)
5°F	1–2 hours
10°F	2–4 hours
20°F	4–7 hours

Cold weather, wind, and removing the cover can all increase heating time.

If you lower your spa to 90°F during the week but want to soak at 102°F on Friday evening, plan to raise the temperature several hours beforehand.

Is It Better to Turn the Hot Tub Off?

In most cases, no.

Modern hot tubs are designed to stay full of heated, circulating water.

Turning the spa completely off can lead to:

Poor water quality
Increased chemical problems
Longer reheating times
Risk of freezing during cold weather

Unless you’re draining the spa or winterizing it, it’s generally better to leave it running.

Does Outside Temperature Matter?

Absolutely.

The colder it is outside, the harder your heater must work.

Factors that affect operating costs include:

Air temperature
Wind exposure
Quality of the insulated cover
Cabinet insulation
How often the cover is opened

During extremely cold winters, keeping the cover closed whenever the spa isn’t in use can save far more electricity than lowering the thermostat a few degrees.

Should You Use Economy Mode?

Many modern hot tubs include an Economy Mode or Vacation Mode.

Instead of maintaining temperature continuously, these modes only heat the water during scheduled filtration cycles.

They’re ideal if:

You won’t be using the spa for several days.
You’re trying to reduce electricity use.
You’re away from home.

Just remember the water may be cooler than the set temperature between heating cycles.

Common Mistakes

Avoid these common errors:

Turning the spa completely off during winter.
Forgetting to replace the cover after use.
Lowering the temperature every night if you use the spa daily.
Expecting the water to heat back up immediately.
Ignoring Vacation or Economy Mode when leaving for extended periods.

Frequently Asked Questions

Is 80°F too cold for a hot tub?

Not for storage or vacations. However, it won’t be comfortable for soaking and may take several hours to return to normal temperature.

Will lowering the temperature damage my hot tub?

No. Lowering the temperature within the manufacturer’s recommended range won’t harm the spa.

Does turning the temperature down every night save money?

Usually not enough to justify the inconvenience if you use the spa regularly. Frequent reheating offsets much of the savings.

What’s the cheapest temperature to maintain?

The lower the water temperature, the less energy the spa generally uses. However, lowering it too much means longer reheating times and less convenience.

Should I turn the spa off when I’m away?

Generally, no. It’s usually better to lower the temperature or use Vacation Mode rather than shutting the spa off completely.

Final Thoughts

For most hot tub owners, the best approach is simple:

Use the spa daily? Leave it around 100–104°F.
Only use it occasionally? Lower it slightly between uses.
Going on vacation? Use Economy or Vacation Mode, or reduce the temperature to around 80–90°F.

Modern hot tubs are designed to maintain water temperature efficiently, so keeping the spa warm is often more practical than repeatedly cooling it down and waiting hours for it to heat back up.

Written by Dan Harvickson (Founder of Last Mountain Tech) Pool and Spa Specialist

What Temperature Should You Keep Your Hot Tub When You’re Not Using It?