When to Close Your Pool in Myrtle Beach, SC: Deadline, Window & Checklist

Myrtle Beach closing dates at a glance

Myrtle Beach's 131-day warm season leaves comfortable margins on both ends — the windows above aim you at the cheap-chemistry versions of each transition.

Put dates aside and follow the water: the Myrtle Beach curve says roughly 59°F by mid-April, 75°F by mid-June, 79°F in mid-August, then back down through 67°F in mid-October. The summer ceiling sits near 79°F, and every window above is just a line drawn on this curve.

The 12-step Myrtle Beach winterizing checklist

The order matters more than the date: balanced water first, verified-dry lines before anything else freezes-proofs, and the cover only after everything below it is done. Work the list inside the window above.

1. Balance the water a few days ahead

   Start midweek for a weekend close: bring alkalinity and pH into their label ranges and let the water settle. What you seal under the cover is what the pool soaks in until spring.

2. Deep-clean the pool

   Leave nothing organic behind: skim the surface, brush every wall and step, vacuum the floor slowly. What goes under the cover dirty comes out worse — winter only ever compounds what it's given.

3. Service the filter one last time

   Clean media goes into storage, dirty media comes out worse: backwash the sand or DE, rinse the cartridges, all per the manual, before anything drains.

4. Apply winter chemicals per label

   Winter chemicals go in before shutdown, not after: label-dosed, circulated for a few hours, distributed evenly. A floater dropped on still water protects one corner.

5. Lower the water level

   Take the level down only as far as the cover's manual says — usually just below the skimmer for solid covers, higher for many mesh systems. An empty pool is never the goal; shells crack and shift without water's weight.

6. Blow out the lines and plug returns

   Air through every line — skimmer, returns, cleaner — until each blows dry mist, plugging returns while the air still pushes. Nothing else on this list protects as much plumbing per minute.

7. Protect the skimmer

   Seat a skimmer guard or bottle in the throat — ice that forms there needs a sacrifice, and a two-dollar bottle beats a plumbing repair under the deck.

8. Add pool antifreeze where blowouts fall short

   Doubt is the criterion: any run you can't confirm dry gets pool-grade antifreeze at the label's per-foot rate. The automotive jug from the garage is for cars — it has no business in pool plumbing.

9. Drain the equipment

   Every vessel on the pad — pump, filter, heater, chlorinator — gets its drain plugs pulled. Drop all the plugs in the pump basket; that's the one place everyone looks first in spring.

10. Set the air pillow and cover

    Center an inflated air pillow, then fit the cover and secure it with water bags, cable, or straps as designed. The pillow gives ice a place to push besides your walls.

11. Shut down the heater carefully

    Follow the manufacturer's winterizing sequence for your heater — drain it fully and, for gas units, close the supply valve. Heat exchangers are the most expensive freeze casualty on the pad.

12. Note this year's dates

    Jot down when Myrtle Beach's water actually cooled and when you closed. A two-line note beats memory next October 26 — your own yard runs a few days off any model, including ours.

What to buy before the rush

Every item below sells out somewhere in South Carolina every October. Stocking the short list before the rush costs nothing extra and saves the mid-project store run — the chemicals guide explains what each category actually does.

• Pool antifreeze

  For lines you can't verify dry — pool-grade only, per label.

• Winter closing kit

  Closing chemistry in one box, dosed by pool volume.

• Air pillow

  Centers under the cover so ice pushes inward, not outward.

• Winter cover

  Measure with overlap; the winter workhorse over everything else.

• Cover pump

  Standing water is a cover killer; this is the counter.

• Expansion plugs + skimmer guard

  The blowout's finishing move — one per return, one for the skimmer.

How Myrtle Beach compares locally

Two nearby data points to triangulate with: Florence, 61 miles from Myrtle Beach, models its close at November 6 (1 day later); Wilmington, 67 miles out, at November 8. Myrtle Beach's own window ends November 5. For the other half of the calendar see when to open in Myrtle Beach, or scan the full year on the season page.

The measuring stick here is Myrtle Beach — 4.7 miles to the northeast, elevation about 39 feet. Its 1991–2020 record is what the model reads for Myrtle Beach; your backyard in Horry County will run a touch warmer or cooler with shade, wind, and pavement, which is exactly the slack the two-week lead absorbs.

Field notes for Myrtle Beach owners

The fifteen-minute monthly walk-around

Once a month all winter: pump or siphon standing water off solid covers, re-tension straps or top up water bags, confirm the level hasn't dropped enough to strand the cover, and glance at the pad for critter nests. Every major cover failure starts as a skipped walk-around.

Cover pumps die in the cold — plan for it

A cover pump left running into a hard freeze can lock in ice and burn out. On freezing forecasts, pull it, let the storm pass, and put it back for the melt. Automatic models with freeze protection earn their price in exactly one forgotten weekend.

The warm spell after you closed

A 78°F week in October doesn't mean reopening. Water under an opaque cover warms far less than air suggests, and a closed, balanced pool tolerates a warm stretch fine. Check the cover pump has somewhere to send rain, enjoy the weather, and leave the plumbing sealed.