Table of Contents
When to Close an Above Ground Pool
Same rule as any pool: wait until your water temperature holds below 65°F, measured mid-afternoon, for about a week. Close warmer than that and the winterizing chlorine burns off in weeks while algae grows under the cover all fall — the classic recipe for a green spring opening. Close below 65°F and your chemicals last until spring.
Above ground pools do get closed slightly earlier than inground pools in practice, for two honest reasons: the flexible hoses and exposed plumbing sit in open air and freeze much faster than buried pipe, and since you can close it yourself in an afternoon, you're not waiting on a service company's schedule.
Not sure about your timing? We built a full breakdown of closing windows by state — the 65°F rule, first-freeze deadlines, and an interactive picker. See When Should You Close Your Pool?
The Golden Rule: Never Fully Drain It
The water in your pool is structural.
An above ground pool's walls are held rigid by the outward pressure of the water. Drain it completely and you have a thin steel or resin ring standing in the wind — empty pools sag, buckle, and collapse. Meanwhile the vinyl liner, once exposed to air, shrinks within days, turns brittle in the cold, and pulls out of its track. A shrunken liner does not go back, even if you refill quickly. A full drain to "protect" the pool routinely destroys both the liner and the pool.
Everything in this guide follows from that rule. You'll lower the water at most about 3 inches below the skimmer — or not at all, if you use a skimmer cover plate (Step 6). Ice management is handled by the air pillow (Step 9), not by removing water.
The one exception: soft-sided pools (Intex, Bestway, Summer Waves) in freezing climates, where the manufacturer's instruction is the opposite — drain, dry, and store the whole pool. That's covered in its own section below.
Supplies & What It Really Costs
First-year DIY runs about $150–275, and most of it — the cover, pillow, plate, clips, and cover pump — is reusable, so later years cost a fraction of that. A professional above ground closing runs $150–300. For comparison, the repairs from a botched closing (cracked skimmer, ruined liner, split pump housing) run from $350 into the thousands.
| Item | Typical Price | Notes |
|---|---|---|
| Winter cover (w/ cable & winch) | $50–150 | Solid blocks all light; mesh drains through. Reusable 6–10+ yrs |
| Air pillow (4×4 or 4×8) | $10–30 | The ice compensator — see Step 9 |
| Winter chemical kit | $30–80 | Sized to gallons; or buy winter algaecide à la carte |
| Skimmer cover plate (Aquador-style) | $26–34 | Optional but excellent — lets you skip lowering the water |
| Winter plugs (return) | $5–15 | Winterizing plug kit |
| Cover clips (set) | $10–20 | ~2 per upright against wind |
| Cover pump | $50–130 | For solid covers; reusable for years |
| Pool antifreeze | $10–20/gal | Usually unnecessary for above grounds — see Step 8 |
You'll also want a reliable water test kit for the chemistry steps — closing on strip-guesswork is how pools open green.
Steps 1–5: Get the Water Ready
1Deep Clean
Brush the walls and floor, vacuum thoroughly, and skim everything off the surface. Any leaves or organic debris you close over become winter stains on the liner and food for spring algae. This is also your last easy look at the liner and wall — note any wear now, while you can still see it.
2Balance the Chemistry — Aim High
Test about a week before closing day, and target the upper end of each range — levels drift downward all winter and you can't adjust a closed pool:
- pH: 7.4–7.6, toward the top
- Total alkalinity: 100–150 ppm (~125 is the sweet spot)
- Calcium hardness: ~200 ppm
- Chlorine: 1–3 ppm (you'll shock separately)
Adjust alkalinity first, then pH — alkalinity moves pH, not the other way around. Need exact doses for your gallons? Use our pool chemistry calculator.
3Shock the Pool
Dose about 1 lb of shock per 10,000 gallons — two to three times that if the water is hazy or has any green tint (our shock calculator does the math). Use fast-dissolving shock on closing day, or regular shock the night before so chlorine can settle before you add algaecide. The old-timer rule holds: you can't open clear unless you close clear. Never close a green pool — fix it first.
4Add the Winter Chemicals
Add the winterizing kit while the pump can still circulate — this is why chemicals come before teardown. A typical kit: winter algaecide, a stain-and-scale preventer, sometimes a slow-release oxidizer floater and an oil-absorbing sponge. Add algaecide only after the shock has settled back down — high chlorine destroys algaecide. And never use a floater loaded with chlorine tablets in a vinyl pool: if it drifts against the wall, it will bleach and weaken the liner where it rests.
5Remove the Accessories
Ladder, steps, solar cover, alarms, toys, automatic cleaner — everything comes out and goes indoors. Left in the water, metal parts corrode and stain the liner, and anything trapped under ice gets destroyed. Rinse, dry, and store where it won't freeze.
Step 6: The Skimmer Decision
This is the fork in the road most guides skip past, and it decides your water level for the whole winter. The problem: water that sits inside the skimmer and freezes will crack it. There are two legitimate solutions — pick one.
Option A: Skimmer Cover Plate
Keep the water at normal level. Remove the skimmer basket, screw a winter faceplate (Aquador-style, ~$26–34) over the skimmer opening from inside the pool, snap on its freeze-proof lid, and disconnect the hose underneath.
Why it's usually the better choice: a fuller pool means more wall support and more stability in wind, you waste no water or dissolved chemicals, and there's nothing to refill in spring. Plates are model-specific (wide-mouth, Doughboy, standard 8×8), so match yours before closing day.
Option B: Lower the Water
Drop the water to about 3 inches below the skimmer opening — just enough that water can't get in and freeze. Use a submersible pump or siphon, and stop the moment you're below the mouth.
When it's the right call: no matching cover plate exists for your skimmer, or the skimmer already leaks. Remember the golden rule — never lower more than necessary, because every inch removed is wall support removed.
Steps 7–8: Plumbing & Equipment
7Plug the Return
Unscrew the eyeball fitting from the return, then seal the opening from inside the pool with a threaded winter plug or a rubber expansion plug. With the skimmer protected and the return plugged, no water can enter the plumbing — which is the entire game.
8Drain & Store the Equipment
Hoses: unclamp, drain completely, let them air-dry, and store them flat indoors — coiled hoses trap water that freezes and splits them.
Pump: remove its drain plug(s), and drop every plug you pull today into the pump basket — spring-you will thank fall-you. Bring the pump inside.
Sand filter: set the multiport valve to its "Winterize" position — the half-notch between settings that lifts the internal diverter off its seat so trapped water can expand harmlessly (no winter notch? park the handle between any two positions). Pull the bottom drain plug and the sight glass. If the tank is too heavy to move, it can stay outside with every plug removed.
Cartridge filter: drain the tank, pull the cartridge, rinse it (a filter-cleaner soak is even better), leave the valves open, and store the cartridge indoors.
Chlorinator: drain it completely and store indoors. Never put antifreeze in a chlorinator — antifreeze and concentrated chlorine react dangerously.
Salt system: remove the cell, clean it, and store it indoors — a freeze-cracked cell is a $500+ replacement.
O-rings: hit them with a Teflon-based lube before storage so they don't dry out over winter.
The Antifreeze Myth
Most above ground pools don't need pool antifreeze at all — when you remove and store the flex hoses, there's no plumbing left to freeze. It only earns its place if your pool has hard-plumbed PVC runs (blow the lines out first; pool antifreeze is the backup, not the plan) or equipment that must stay outdoors. If you do use it: always pool-grade propylene glycol — never automotive antifreeze, which is toxic to people, pets, and your spring water.
Step 9: The Air Pillow (Most Misunderstood Step)
The air pillow is not there to hold the cover up. It's an ice compensator. When the surface freezes, the ice sheet expands — and in a closed circle, that expansion pushes outward against your thin steel or resin walls and your skimmer. A soft pillow floating in the middle gives the ice something easier to squeeze: it compresses inward against the pillow instead of straining the walls. As a bonus, it breaks the ice into a manageable sheet that melts faster and lifts off easier in spring.
Doing it right
- Inflate only 50–60%. A drum-tight pillow can't compress — it just pops under the first heavy ice or snow load. Squishy is correct.
- Tape the valve (and seams on a cheap pillow) with duct tape to slow the inevitable air loss.
- Center it with thin ropes run across the pool and tied to the top rails, through the pillow's grommets. An off-center pillow does half the job.
- One 4×4 pillow suits pools up to ~24 ft round; go 4×8 (or two pillows) for larger pools and ovals.
If the pillow deflates mid-winter, don't panic — even a partially deflated pillow still interrupts the ice sheet, which is most of its value.
Steps 10–11: Cover It and Keep It Covered
10Install the Winter Cover
Drape the cover over the pool and pillow, then thread the cable through the cover's grommets and tighten it with the winch below the top rail so wind can't get underneath. Add cover clips over the top rail — figure about two per upright, roughly every 16–18 inches — for gusty sites. Pools with a surrounding deck can't cinch a cable, so use water bags or cover-seal wrap instead.
Never weight a cover with bricks or stones. When (not if) one gets knocked in, it lands on your liner. A solid cover blocks all light for the cleanest spring water but needs a cover pump; a mesh cover drains through and skips the pump, but passes enough light that you should close later and open earlier.
11Winter Upkeep
A closed pool isn't a sealed pool. Through the winter: pump standing water off the cover before it freezes into a several-hundred-pound ice lens (this is what the cover pump is for), keep the skimmer area ice-free, and re-check the cable tension after every storm. In heavily treed yards, a leaf net over the cover — removed after leaf-drop, before the first snow — saves the cover from a rotting leaf mat.
Critter note: a covered pool and a dry pump shed are prime winter real estate for mice, and they chew liner, solar covers, and pump wiring. Store equipment off the ground, stuff steel wool into gaps, and drop a couple of mint sachets in with stored gear.
Intex, Bestway & Soft-Sided Pools: A Different Answer
Soft-sided pools break the golden rule on purpose — because their walls aren't rigid, the calculus flips. The decision comes down to one number:
Winters hit 41°F (5°C) or colder
Drain it, dry it, and store it — that's the manufacturer's instruction. Freezing water can rupture soft vinyl walls, and a drained pool left standing collapses under snow and wind, so "empty but up" isn't an option either.
- Drain via the drain valve and a garden hose — big pools take 12+ hours, so start the night before
- Dry it completely (trapped moisture = mildew), then dust with talc or cornstarch so the vinyl doesn't stick to itself
- Fold to a 3–4 ft strip, roll, and store at room temperature away from rodents
- Toss the filter cartridge — it's not worth storing a used one over winter
Winters stay milder than that
You can winterize it in place — most sunbelt Intex owners leave them up year-round:
- Plug the inlets and outlets from inside
- Remove and store the hoses, ladder, and pump
- Balance, shock, and add winter algaecide
- Cover it, and keep standing water pumped off the cover
The Regional Playbook
Freeze zones (Northeast, Midwest, Mountain West)
Run the full 11 steps. The pillow, cover, and skimmer protection are non-negotiable, and everything drainable gets drained. Close once water holds below 65°F — typically September to mid-October.
Mild & transition climates (mid-South, coastal)
Consider "active winterization" instead of a full close: leave the pool full and running 2–4 hours a day at reduced maintenance, run the pump continuously through any hard-freeze night, and hit it with a mid-winter shock and algaecide — algae never fully sleeps here.
Sunbelt (FL, southern TX, AZ, southern CA)
Most owners never close: shorten pump hours, keep chlorinating lightly, and run the pump through the rare freeze warning — moving water rarely freezes. Soft-sided pools here can stay up year-round.
Not sure which track you're on? The closing windows by state guide maps every region to its window and first-freeze deadline.
Frequently Asked Questions
Should I drain my above ground pool for the winter?
What does a pool air pillow actually do — do I need one?
Do I need to winterize an Intex or Bestway pool, or take it down?
Do above ground pools need pool antifreeze?
How far below the skimmer should I lower the water?
When should I close my above ground pool?
What chemicals do I add when closing?
Do I take the pump and filter inside?
Rather Have a Pro Handle It?
An Above Ground Closing Runs $150–300 — Freeze Damage Runs Much More.
A cracked skimmer, a shrunken liner, or a split pump housing all cost more than a decade of professional closings. If you'd rather not gamble the liner, a local pro can close it in an hour.
Related: Full Winterization Guide · Opening & Closing Checklist