12 Things You Must Do When Closing Your Swimming Pool For Winter.

An above ground swimming pool with a cover over it.

Having fun with your family for several hot summer months in your swimming pool is the best part of being a swimming pool owner.  Unfortunately in most regions unless you have an indoor pool or special circumstances, the pool will be closed during the cold and frigid winter months.

There are a few things that you must do at the end of the pool season to make sure your pool remains in good condition throughout the off season.

Failure to properly close your swimming pool will likely result in your pool becoming dirty, green or damaged during the non swimming season.

Improperly closing your swimming pool can result in some of the following issues.

  • The pool becoming extremely cloudy.
  • Algae thriving in your swimming pool.  Even though algae cannot grow in the winter, if you don’t follow the steps I give, your pool may become a swamp looking pond, rather than a beautiful swimming pool.
  • Busted hoses or pipes from extreme cold temperatures.
  • Liner damage that may be beyond repair resulting in maintenance costs.
  • A dreadful opening of the pool next season.  When you officially close your swimming pool for the season, you will not be performing any maintenance, adding chemicals or even looking at it until next season.  It is closed and should require no attention.  If you fail to follow the proper steps, you may spend 1 or 2 weeks cleaning, repairing and prepping your pool next year.

I may not give the same advice that others give when it comes to closing your swimming pool and that is fine.  Some people may choose to end the season at different times or with different chemicals or methods.  There really isn’t a wrong way, as long as the way you close your pool allows for a smooth opening next season.

The way I have closed my swimming pool for the past 3 years has worked amazingly.  As a matter of fact once I remove the cover from the pool each season, the water looks the same as when it was covered, with no chemicals or extraordinary amount of money spend at the end of the season.


Closing your pool really is not that hard.  It can be done in one afternoon when you decide based on the current weather, forecast and season that it is time to shut the pool completely down.

This brings me to one of the most important things to look at when closing your swimming pool is the water temperature.  It is never a good idea to close your swimming pool simply because the water is too cold for swimming.

The water may not be suitable for swimmers, however it still may be suitable for algae growth.  If algae can survive in your water a few weeks after you stop swimming, closing your pool at this time will invite algae to grow and turn your water green going into the following season.


As the season’s end is getting near, keep up with your regular maintenance and water checks. You will want to keep your chlorine levels between 1 – 3 PPM during this time as well to prevent any algae from forming.

It is also necessary to be sure that your pH, alkalinity and water hardness are within the recommended ranges.

pH7.2 – 7.6 ppm
Alkalinity80 – 120 ppm
Hardness150 – 400 ppm
Recommended levels for your swimming pool.

When your swimming pool is going to be inactive for several months, it is best to make sure that you have balanced the water accordingly.

Not only will this make it a much easier opening experience at the beginning of the next season, but will also help prevent damage to your liner and pool parts during the winter.


It is best to keep your pool open for a few weeks to a month after you no longer use your swimming pool.  Do not think of closing your pool as meaning the water is too cold to swim in.  This is what causes many people to allow there pools to become algae infested over the off season.

Algae can develop, grow and stay alive when the water temperature is above 65 degrees.  I talk about this in another article of mine that called “What is the best time to close  your swimming pool for the season“.  This article talks about continuing to chlorinate your water awhile longer to keep your pool clean.

It is best to get the average water temperature about once per week.  Check the temperature in the morning hours when the water is cool, and again in the evening.  Add those two temperatures together and divide that number by 2.  This will give you the average water temperature of your swimming pool.

(Morning water temperature + Evening water temperature) ÷ 2 = Average Water Temperature

Once the water temperature average is below 65 degrees, algae can no longer survive, so now it is time to officially close your swimming pool for the season. 


Remove any leaves, grass, bugs and other debris that are floating on the swimming pools surface.

Check and clean skimmer baskets, remove any objects such as toys and floats that may have been left in the water or been caught by the filtration system.


Once you have determined it is time to close your pool, it is best to give it a good cleaning on the bottom.  If you have been maintaining your swimming pool properly during the regular season, this should be an easy task.

Simply connect your pool vacuum and hoses to your pools filter and run the vacuum head along the bottom of the pool slowly so that all the debris that has settled on the bottom will get vacuumed into the pools filter.

While this step may not be completely required, it is much more enjoyable to remove the cover the following season and see a nice clean pool with no work required.  Performing this quick and easy step will help achieve that.


This step should not be done until you have vacuumed your pool.  Once you have done so, for sand filters backwash your filter for about 2 minutes or until the water is completely clean.  If you have a cartridge filter, clean them with a water hose until the dirt has been completely removed.

If using the sand filter don’t forget to run the rinse cycle for at least 30 seconds after you compete your backwash and before turning the pool pump off.


While this isn’t required, it is best to go ahead and give your pool a final shock of the season to allow it to kill off any bacteria that is lingering around in the water.

After you have added your pool shock, run the pump several hours like you normally would overnight.

Continue to run the pool pump during any upcoming days until you are ready to officially close your pool. You should go ahead and proceed to the following steps within a few days after shocking your pools water.


To avoid water from remaining inside any of the hoses which can cause them to freeze and break during the winter, you will need to drain the water from the pool several inches until it has fallen below the water return.

There are a few ways you can accomplish this, however never leave your filter in backwash mode for a prolonged period of time to reduce the water in the pool.  This can cause damage to the pool filter.  If using this method, use the waste selection on the filter instead.

  • Turn your sand filter to WASTE and allow the pump to start draining water from the swimming pool.  This will only work until the water level has become too low for the pump to siphon water from the pool.
  • Remove the plug if attached to your pool so that water will drain from the sidewalls or bottom until the water has drained to your desired level.
  • Remove the sand filter plug on the bottom.  This sometimes does not work particularly well, because the sand in the filter blocks the water from exiting the filter.  This could cause a lengthy and non productive way to attempt and drain your pool water.
  • A submersible pump is one of the easiest ways to lower the water levels.  Place the pump in the water and hook your water hose to it and it will begin draining your pool until you turn the pump off.
  • The method I usually use is disconnecting the return hose from the pool filter.  This will cause all the water to drain on the ground from the return until it has fell below the return.  When using this method, I recommend using the WASTE selection on your sand filter first if possible until the water levels are too low.  This method will create a quite of a bit of water around your pool until it drys.


Water temperatures below 32 degrees freezes, and when water becomes ice it expands.  When this happens it will cause your swimming pools hoses, pipes and filter to bulge and ultimately cause them to bust resulting in expensive repairs.

Just because you drained the water below your pool return and skimmer, there is a good chance water is still standing in the filter, pump and other areas including your hoses.  Disconnect all of them to allow any water that was remaining to drain.


It is best to have a dedicated power box near your swimming pool that was installed by a certified electrician.  If you have one of these, turn the power off to that box for the off season.  This can usually easily be done by flipping a breaker switch.

If you are using an extension cord or other form of powering your swimming pools pump system (not recommended), disconnect all cords and remove them from the outdoor elements for the off season.

With the potential of cold rain, snow and other mother nature events developing during the winter, to prevent electrical shock, it is safest to have your power turned off and any live lines removed during these times.


The pool pump is best if kept in a dry environment during the off season.  While some pool owners chooses to leave there pool pumps hooked up during the winter, I do not recommend this.

When rain falls that freezes along with snow and ice, it can become covered on your pump.  Once frozen it can cause issues at the start of the following season.

I myself one season was lazy and left the pump attached to the pump mount over the winter.  We had at one time snow that completely covered the pump.  It also was not a huge surprise when I tired powering it up the following season and only received a humming sound.

Fortunately I was able to remove the cover of the pump and lubricate the teeth slightly and free up the motor.  I am confident this would have never been an issue at all if the pump was placed in a dry and warmer location for storage.

Most pumps are easily removed with 1 or two screws and an inlet and outlet hose connection.  Disconnect hoses and necessary mounting screws from the pump and place it in your shed, garage or house until the next swimming year.


A blown up air pillow will float on the top of the pools surface and can be purchased in various sizes depending on the size of your pool.

I have went a season with and without an air pillow, and do recommend using one.  The main reason is when you get precipitation, whether it is rain, sleet or snow on the cover it will weigh it down.

The air pillow is full of air and will be under your pool cover.  It will prevent large amounts of rain or heavy snow from pushing your cover deeper in the water of the pool reducing stress on your swimming pool sides.

Rubber tires or other safe objects that can be placed on your water and float above can also be used in place of an air pillow.

Some people opt to skip this step, and I have been guilty of that myself.  Based on the way the cover was pushing on my sidewalls without the air pillow that season, I do recommend not skipping this step.  Air pillows can be purchased for around $10 at your local pool stores.  You will then blow them up to full capacity and use them beneath your pools cover.


I honestly cannot stress enough how important this step is.  Pool covers can range and be quite expensive, however if you do some shopping on various websites and local stores you can find a reasonable buy on one.

I purchased the one I have now several years ago from jet.com and still use it today.  I only paid about $30 for it and had a free shipping coupon.  While that price may not be easily found, you can find a pool cover for a decent price and even the lower priced ones seem to work quite well.

Get your family outside and start holding all 4 sides of of the cover and slowly take the cover over the top of the swimming pool.

Be sure not to allow the cover to enter the water.  If water gets on top of the cover it will be weighted down quickly and may make it impossible to place the cover over the top of the pool.

Once you have successfully covered the pool, if your cover has a strap, pull the strap so that the cover is tightened.  I have a dozen clamps from Home Depot that I add as well to make sure the cover is extra secure or check out the tip below and add a cover seal instead.

 When winter winds and blizzard like conditions develop, you want to be sure the cover doesn’t get damaged by wind making its way under the cover.



Blue Wave Winter Cover Seal around pool cover

After you have covered your swimming pool for the winter months you are completely finished and don’t have to worry about it until early next spring.

However for a little extra support for your winter cover and to help reduce any dirt and debris from blowing in your pool water from the sides of the top rails, placing a winter seal cover all the way around your pool is a great idea.

It comes in a roll similar to that of saran wrap. You and a friend need will take it and go round, round and round the pool until you have completely used it all up keeping it as tight as possible.

It may look like the wind will blow it off, but if you have it tight and did it correctly I have had no problems with it lasting the entire off season.


Once you have covered your pool for the winter, you can let it set and wait until the next spring season.

Just like when you close your pool, you must choose the proper time to open it as well.  Waiting to late and algae will begin to grow.

Check out my article titled “How to keep your pool clear year round” that details when it is the best time to open and close your pool for each season.

Recent Posts