Winter is coming—and if you own a swimming pool, it’s time to shift gears from pool parties to pool protection. Forgetting to close your pool properly can lead to frozen pipes, cracked tiles, algae blooms, and costly repairs come spring. According to the Pool & Hot Tub Alliance, improper winterization is one of the top causes of pool damage during the colder months.
The good news? With a solid winter closing checklist, you can protect your investment and ensure an easy reopening next season. In this guide, we’ll walk you through everything you need to do—step-by-step—to winterize your pool like a pro.
1. Balance the Water Chemistry
Before you even think about covering your pool, make sure the water chemistry is balanced. This helps prevent scaling, staining, and algae growth while the pool is closed.
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pH: Keep between 7.2 and 7.6
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Alkalinity: Aim for 80–120 ppm
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Calcium Hardness: 200–400 ppm
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Chlorine: Shock the pool 1–2 days before closing to kill bacteria and algae
Allow the chlorine level to return to normal before adding winterizing chemicals to avoid chlorine breakdown.
2. Clean the Pool Thoroughly
A clean pool is much easier to reopen in the spring.
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Skim leaves and debris from the water surface
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Vacuum the bottom of the pool
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Brush the walls and tile line to remove algae or dirt
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Empty and clean the skimmer and pump baskets
Taking time to thoroughly clean the pool reduces the risk of staining and makes chemical balancing more effective.
3. Lower the Water Level
Depending on the type of pool cover and pool surface, you’ll want to lower the water level below the skimmer.
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Vinyl liner pools: Lower water 1 inch below skimmer
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Concrete or plaster pools: Lower 4–6 inches below skimmer
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With mesh covers: Lower to 12–18 inches below tile
This prevents water from entering the plumbing lines and freezing.
4. Drain and Blow Out the Lines
One of the most important (and often overlooked) steps is removing water from the plumbing lines.
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Use a shop vac or air compressor to blow out the skimmer, return, and main drain lines
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Plug return lines and skimmer with winter plugs
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Add pool antifreeze if you live in a very cold climate, especially for lines that can’t be completely blown out
This step protects your pipes from freezing and bursting.
5. Remove and Store Pool Accessories
You don’t want freezing temperatures to damage your pool equipment or accessories.
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Remove ladders, diving boards, skimmer baskets, and solar blankets
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Store in a dry place away from direct sunlight
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Clean and dry all accessories before storing to prevent mold or corrosion
This helps extend the life of your pool equipment and makes reopening much easier.
6. Add Winterizing Chemicals
These chemicals help maintain water quality and prevent algae growth while the pool is closed.
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Algaecide: A long-lasting formula works best for winter
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Stain and scale preventer: Helps prevent mineral buildup
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Winter chlorine floaters or non-chlorine oxidizers: Keep water sanitized without high chlorine levels
Be sure to follow the manufacturer’s dosage instructions based on your pool size.
7. Cover the Pool Securely
Your pool cover is your first line of defense during the winter months.
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Choose a high-quality cover—mesh or solid, depending on your climate
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Make sure it’s free from rips or tears
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Secure the cover tightly to prevent wind from lifting it
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Use water bags or safety cover anchors to keep it in place
Check the cover every few weeks to remove debris and ensure it’s still secure.
8. Monitor Throughout the Winter
Closing the pool isn’t a “set it and forget it” task. A little off-season maintenance goes a long way.
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Check the cover regularly for sagging, debris, or pooling water
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Inspect water levels every few weeks to ensure no leaks
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Remove heavy snow from the cover using a broom or pool brush
Staying on top of winter maintenance protects your pool from surprise damage.
Conclusion
Closing your pool for the winter might feel like a chore, but it’s a crucial step in protecting one of your home’s most valuable assets. By following this pool winter closing checklist, you’ll prevent winter damage, extend the life of your equipment, and make next season’s opening faster and less stressful.
❄️ Don’t wait until the first frost hits. Use this guide to winterize your pool today—and enjoy peace of mind all season long.