Seasonal care

How to winterize
your pool

By Dominik Graham PritchettUpdated 2 September 2026About 8 min read

Putting a cover on the pool is not enough. To prevent frost damage to pipes, the pump and fittings, prepare the water, equipment and cover as one system. Here is a safe order of work – without applying a winter plan that does not fit your pool.

First decide: store, active winterization or passive winterization?

There is no one correct winter setting. It depends on what your pool and equipment were designed for.

• Seasonal above-ground and quick-up pools: Many models should be completely drained, dried and stored. Check the manual first.
• Winter-proof above-ground and in-ground pools: These can often remain filled with water when fittings, pipes and equipment are protected correctly.
• Active winterization: The system continues to run under a dedicated frost-protection plan. Use this only where the equipment and controller are designed for it.

If you are unsure which method your pool permits, follow the manufacturer documentation or use a qualified pool professional. A one-size-fits-all method is especially risky with heat pumps, salt systems, counter-current units or fixed pipework.

When should you winterize your pool?

Do not wait for the first frost. Prepare the pool once the swim season is over, the water temperature is steadily falling and frost is foreseeable. Depending on the manufacturer, passive winterization commonly begins at a sustained water temperature of around 12–15 °C. At warmer temperatures, algae and deposits can still develop under the cover.

The safe order for winterizing

1. 1Check manuals and equipment
   Note the pool model, filter, heater and any special equipment. Before doing anything, identify the specified winter position, plugs and water level.
2. 2Clean the pool thoroughly
   Remove leaves, dirt and deposits from the waterline, walls and floor. Clean the skimmer basket and filter according to the manual.
3. 3Check water treatment
   Prepare the water according to your treatment system and product label. Do not shock-chlorinate immediately before passive winterization: chlorine breaks down slowly in a cold, covered pool.
4. 4Protect the water level and fittings
   Lower the water only to the level specified for your pool – often at least about 10 cm below the lowest fitting. Use suitable winter plugs or protective parts for skimmers, return jets and other openings.
5. 5Drain pipes and equipment completely
   No water may remain in frost-exposed components. Drain pipes, pump, filter tank, valves, heat pump and extra equipment as directed. Store removable devices dry and frost-free.
6. 6Remove accessories
   Take out ladders, robots, thermometers, hoses and loose accessories. Clean, dry and store them frost-free.
7. 7Cover and secure access
   Use ice-compensation floats only where they are intended for your pool, then fit the correct winter cover as instructed. A cover is not automatically a child-safety device; secure access separately.

Check occasionally throughout winter

A passively winterized pool needs little work, not no attention. After storms, heavy rain or snow, check the cover, its fastenings and the water level. With active winterization, the pump and frost-protection system must be monitored as part of the plan.

Common mistakes

• Starting too late: above-ground equipment can be at risk before the pool freezes.
• Guessing the water level: pools are not all drained to the same height.
• Draining only the pump: pipes, valves and other devices can retain water too.
• Confusing winter chemicals with antifreeze: water treatment does not protect equipment from frozen water.
• Treating the cover as a safety barrier: an ordinary winter cover does not secure access.

Technical orientation: BAYROL and Steinbach, accessed 2 September 2026. The instructions for your own installed products remain authoritative.