What Is the Best Pool Cover to Retain Heat?

Swimming Pools Blog

Short answer: For day-to-day swim season heat retention, a solar cover (solar blanket) is the most effective and affordable option. For the off-season, a solid winter safety cover or an automatic safety cover minimizes heat loss by blocking sunlight and evaporation—while also keeping your pool secure. (Read more)

Why heat escapes—and how covers stop it

Most heat loss happens two ways: evaporation and radiation. Any cover that reduces evaporation will dramatically cut heat loss; blocking sunlight and shielding the surface further stabilizes water temperature. Solar blankets excel at in-season evaporation control, while solid safety covers and automatic covers add the benefit of complete light blockage and a tighter seal in the shoulder and winter months. (Read more)

The contenders (and when each is “best”)

1) Solar cover (solar blanket) — Best for active swim season heat retention

  • Purpose: Trap heat and reduce evaporation when you’re swimming regularly.
  • Why it wins: Noticeably boosts and holds temperature overnight and on cool, breezy days, with a low upfront cost and easy handling.
  • Good to know: Solar blankets are not safety covers; pair them with appropriate safety measures. (Read more)

Pick a solar cover if: You want the warmest water for the lowest cost during spring, summer, and early fall.

2) Solid winter safety cover — Best for off-season heat retention & clean openings

  • Purpose: Close the pool safely while minimizing winter heat loss and algae risk.
  • Why it wins in winter: A solid safety cover blocks 100% of sunlight, which helps the water stay more stable and reduces springtime reheating and cleanup. It also prevents debris and discourages algae growth for a faster, cleaner opening. (Read more)

Pick a solid safety cover if: You’re winterizing and want maximum protection and the most stable water heading into spring.

3) Mesh winter safety cover — Best for low-maintenance winter protection

  • Purpose: Secure the pool with easy drainage of rain/snow.
  • Heat notes: Mesh covers are lighter and drain well, but they allow some light through, so they’re slightly less insulating than solid covers. Choose higher-density mesh for better light blocking if you prefer lighter handling over maximum heat retention. (Read more)

Pick a mesh safety cover if: You value light weight and easy drainage, and you’re okay with a modest trade-off in heat retention versus solid.

4) Automatic safety cover — Best all-around, year-round heat savings (premium)

  • Purpose: Daily, push-button protection that reduces evaporation and guards the pool whenever it’s not in use.
  • Why it helps heat: Tight seals curb evaporation day and night, improving heater efficiency across much of the year (and simplifying safety). (Read more)

Pick an automatic cover if: You want convenience + heat savings year-round and are comfortable with a higher investment.

Recommendations by scenario

  • “I want the warmest swim water this season for the least cost.”
    Choose a solar cover and use it whenever you’re not swimming. (Read more)
  • “I’m closing the pool and want the cleanest, most stable spring opening.”
    Go with a solid winter safety cover. If you prioritize lighter weight and drainage, pick high-density mesh. (Read more)
  • “I want one solution that saves heat all the time and is easy to use.”
    Consider an automatic safety cover. (Read more)

Get the right cover—custom-measured for a perfect fit

Calm Water Pools offers premium Latham® winter safety covers (solid and mesh), custom-measured to your pool’s exact shape and features. We do not perform installations. Latham will arrange free pickup of your existing cover, measure it for accuracy, and provide an exact estimate before your new cover is made—so you get a precise fit without guesswork. Most orders are completed quickly (seasonal timing applies). (Read more)

👉 Learn more or request your estimate: Winter Safety Covers

Quick FAQs

Will a cover really help my heater?
Yes—reducing evaporation is the single biggest heat saver. Any well-fitted cover helps; solar covers and automatic covers shine during swim season, and solid safety covers excel during winterization. (Read more)

Mesh or solid for winter heat retention?
Solid retains heat better by blocking sunlight completely; mesh trades a bit of heat retention for easier handling and drainage. (Read more)

Do you install covers?
No—Calm Water Pools sells the covers. Latham coordinates free pickup/measuring and provides your exact quote before production. (Read more)

Bottom line

  • Best at retaining heat in season: Solar cover.
  • Best at retaining heat in the off-season: Solid winter safety cover (with mesh as a lighter, lower-maintenance alternative).
  • Best all-around (premium): Automatic safety cover.

When you’re ready, explore Winter Safety Covers and get a custom-measured solution for your pool. (Read more)