Closing an In Ground Pool for the Winter

You should close your pool ahead of the frost to keep your equipment and water lines from freezing. Try not to close your pool too early though - if you wait until the water temperature is consistently below 15 degrees Celsius (60 degrees Fahrenheit) then you'll have less algae growth throughout the Winter season. The following guide will work for inground pools sanitized using chlorine or salt water.

Step 1) Get your equipment organized

Before you close your pool check your equipment to ensure it's in good shape and you have everything you need. This includes:

  • - Your winter cover - check for rips or tears. Try repairing small rips or tears with a vinyl pool patch (for vinyl covers) or pool cover patch tape (for lightweight covers)
  • - Water bags - check for leaks and ensure you have enough bags to cover the perimeter of your pool
  • - Your skimmer plugs (Gizzmo is recommended) - check for cracks or holes
  • - Return jet plugs - check for cracks or holes
  • - Winter chemicals (including shock, algaecide, stain and scale remover - for salt water pools, be sure to use a non-chlorine shock treatment)
  • - Air compressor or a powerful shop vac to clean out the lines.

TIP: Purchase one of our pool closing kits to get all of the winter chemicals you need in one handy package! Plus, our deluxe pool closing chemical kits include a non-chlorine shock, perfect for use with both chlorine and salt water pools.

Step 2) Prepare the pool

  • - Remove the diving board (including bolts), flotation devices, ropes, toys and any other pool accessories before cleaning, drying and storing for the winter
  • - If you have a water slide or waterfall you will need to drain and blow out the piping systems

Step 3) Prepare filters and pumps

  • - Disconnect your pump and filter, ensuring the pump is completely drained
  • - If your pump and filter system have quick disconnect fittings or unions then you should unscrew them, ensuring all water has been removed
  • - After you've disconnected the pump, pull out the drain plug and completely empty all the water
  • - Leave the pump drain plug out and store it in the basket for the spring
  • - Clean the filter and drain the filter tanks, remembering to leave the backwash valve open:
    • If you have a sand filter then unplug the drain plug and leave it open, making certain that the multi-port valve is completely drained
    • If you own a cartridge filter unit then disconnect it from your lines, clean the cartridge and remove all water
  • - Blow the multiport valve out with a shop vac or compressor until all water is removed
  • - Remove jet fittings
  • - After you've drained your pump turn it on only for a second to remove the water. If you turn the pump on for too long you can damage it
  • - Store the pool pump and filter in a dry place for the winter

TIP: Put your drain plug, fittings and other small items in the pump basket so you can find them easily come spring.

Do you need a new filter or pump? Shop online now.

Step 4) Prepare your pool heater (if applicable)

  • - If you have a pool heater ensure you drain it completely, then blow out the lines with a shop vac or compressor
  • - Pull out all drain plugs and use the shop vac to blow out the lines. Leave the drain plugs out, but remember where you store them. You'll need them in spring.
  • - Check your heater's instructions to see whether the manufacturer recommends removing the heater tray

Is your family complaining about the temperature of your pool? Browse our pool heaters to find the right option for your pool.

Step 5) Drain and blow out your lines

TIP: Avoid using anti-freeze, which can cause a mess when you open your pool. Anti-freeze is not necessary if your lines are properly blown out.

  • Use a shop vac or a compression pump to blow out the water from your plumbing lines:
    • - Hook up your compressor or shop vac to the return lines of the filter system. Or you can screw the compressor fitting into the drain plug of the pump
    • - Keep the air blowing until air bubbles are visible from the return jets in the pool. Put a plug in the fitting under the water when you see the bubbles blowing. It's very important to make sure you plug the jet tightly
  • - Ensure you drain the water from each line (don't forget any) and that you plug each line once it is clear and empty
  • - If you have a main drain line you can create an air lock by blowing out the line until bubbles appear from the drain, at which time you can plug the line by closing the valve

What type of plugs should you use?

Threaded plugs are best. Plugs with rubber gaskets or 'O' rings help form a proper seal so that water does not enter the line. If your pool fittings are not threaded you'll have to use a rubber freeze plug.

Step 6) Plug the skimmer hole

Many people prefer to use a Gizzmo, which allows for expansion without damaging the skimmer system. A Gizzmo is a hollow tube that collapses if water gets into the skimmer and freezes. It is a great device to help you seal the skimmer line.

Another option is to use a skimmer plate over the mouth of the skimmer. The Skimsaver is a plastic plate that keeps water out of the skimmer. The benefit of using a skimmer plate is that you can leave the water level up for the winter season. A skimmer plate is only recommended for use in pools with vinyl linings.

To plug your skimmer hole:

  • - Remove skimmer baskets
  • - Lower the water below the mouth of the skimmer
  • - Blow out all the skimmer pipes using your shop vac or compressor pump
  • - If you're using a Gizzmo make sure you put tape on the threads before you install it to ensure a tight seal

Step 7) Balance your chemicals

Whether you have a salt water or chlorine pool, you want to ensure your water chemistry is balanced before closing up for winter. Balancing the following areas will help you protect your pool liner from staining:

  • - Total pH
  • - Total alkalinity
  • - Calcium hardness

A Closing chemical kit will keep your water cleaner for the next season. Make sure that any granular chemicals are well dissolved. Always follow the instructions and test the chemical levels after you've added them to ensure they are balanced.


  • - Use a floater containing chlorine or bromine. A floater could stick against the wall, staining it
  • - Throw chlorine or bromine tablets into the pool, which could stain your pool's liner if they sink to the bottom and don't fully dissolve

Step 8) Install your pool cover

With a winter cover that's properly installed and in good condition, you'll be better able to keep your pool clear of winter debris and you'll have a cleaner pool in spring, which means it'll be easier to open.

Do you have the right cover? Browse our pool covers to see your options.

Installing a Winter pool cover

Lay the cover on the pool and place filled water bags along the edge of the cover, end to end, surrounding the perimeter of the pool. Ensure you place the water bags through the loops on the cover of the pool. Tuck the water bags into the corner pockets of the cover to strengthen the anchoring.

Don’t overfill the water bags because when the water inside freezes they will expand and if the bags are too full they could burst.

Installing a safety cover

If you have a winter pool safety cover then you won't have to deal with water bags. Before installing the cover inspect the condition of the anchors that have previously been installed on your pool deck. They should be in good shape and remain flush with the deck of your pool.

Snap the cover into the anchors, as per the manufacturer's instructions. If you've got a safety cover you should perform light maintenance over the winter months by removing leaves or other debris from the cover with a leaf blower or rake. This maintenance will make opening the pool easier in spring.

Step 9) Clean and store your equipment

Once your cover is in place you can store any remaining pool equipment and accessories in a clean, dry place throughout the winter months.

Closing your pool will protect it during winter and make life easier in spring when it's time to open it up and enjoy it again. Ensure you have properly blown out the lines to remove all water, keep your liner in good shape by ensuring all chemicals are dissolved and in balance, and use a cover to protect your pool from the elements.

Contact us to purchase your winter pool equipment, or ask any questions. Happy hibernating. We'll see you in the Spring!

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