You’ve bought a garden hot tub — or you’re thinking about one — and the first question that comes to mind in September is: what do you do with it in winter? Turn it off and drain it? Leave it running? How much does it cost? What if it freezes? Here are concrete answers.
Can a hot tub run during winter?
Yes — and most customers actually use it the most in winter. Sitting in hot water at -5 °C with a view of a snow-covered garden is exactly the experience many people buy a hot tub for. Quality hot tubs are designed for year-round operation.
How much does it cost to run a hot tub in winter?
The answer depends on two things: insulation quality and outdoor temperature.
Example for a typical winter (average outdoor temperature -5 °C, water set to 38 °C):
- Cheap hot tub without good insulation: €80–130 a month in electricity
- Mid-range (good insulation + a thermal cover): €40–65 a month
- Premium hot tub (full-foam insulation, smart heating): €25–45 a month
The difference is dramatic. A cheap hot tub can cost you two to three times more in winter than a premium one.
What happens if you turn a hot tub off in winter?
If you just turn it off without draining the water, you risk freezing. Water in the pipes and pump freezes during a longer power outage or extreme frost, which cracks components — repairs cost hundreds to thousands of euros.
Winter operation options:
- Leave it running at a reduced temperature (30–35 °C) — you save energy, but the water keeps moving and won’t freeze.
- Turn on frost-protection mode — modern hot tubs have an automatic mode that activates heating only when freezing is a risk.
- Drain and winterize it — if you won’t be using the hot tub all winter.
Practical winter hot tub maintenance: what to do
Every week:
- Check pH level (ideal: 7.2–7.6) and chlorine/bromine
- Remove leaves and debris from the water surface
- Check the filter — it clogs faster in winter
Every month:
- Replace or clean the filter
- Check the cover for tightness — a damaged cover means huge heat losses
- Flush the piping system
At the start of winter:
- Lower the set temperature to 35 °C
- Check the cover’s insulation — if the cover’s core is cracked, replace it
The most common mistakes in winter operation
1. Underestimating the cover — A damaged or old cover (5+ years) loses 30–50% of its insulation. Replacing the cover (€150–500) pays for itself within 1–2 winters.
2. Turning it off without draining the water — You’ll destroy the pump and piping. If you’re not using the hot tub, either leave it in frost-protection mode or drain it properly.
3. Neglected chemistry — Biological activity slows down in winter, but it doesn’t stop — it just becomes less noticeable. Neglected chemistry leads to bacterial growth.
4. Ignoring filters — A clogged filter means the pump works under strain — higher consumption plus a shorter lifespan.
Conclusion: leave it running
A quality hot tub with good insulation and a thermal cover deserves to run through winter. Costs are predictable, the experience is exceptional, and upkeep isn’t harder than in summer.
If you’re considering a hot tub and winter operation matters to you — talk to us. We’ll advise you on which models have the best insulation and the lowest running costs.
