Using a solar pool cover is a big help in preventing heat loss through evaporation. Whether you have an in-ground or above-ground pool, these covers can extend your swimming season—but you need to pick the right cover for your pool. Jimmie Meece, Brand President of America’s Swimming Pool Company, offers this advice: “Ensure that you purchase a cover large enough to cover your entire pool to maximize the solar pool cover’s effectiveness.” He recommends a clear cover with UV-stabilized polyethylene as the best option for heat transfer while minimizing the impact of UV rays on your pool’s chlorine levels.
We researched the best solar pool covers in a variety of shapes, sizes, and materials. We compared based on thickness, which impacts how easy it is to remove and replace the cover, and the color of the cover, since that determines how much heat transfers to the water below the cover while blocking (or allowing) UV rays that can impact chlorine levels.
Robelle Heavy-Duty Blue Solar Pool Cover
Light blue color minimizes changes to water chemistry
Can be trimmed to fit your pool
Lighter and easier to roll up
Available in different shapes and sizes
Not as durable as thicker covers
Warranty period limited to three years
For a solar pool cover that is effective, easy to maneuver, and will minimize UV rays entering your pool water, pick the Robelle Heavy-Duty Blue Solar Pool Cover. The light blue color of this cover allows solar energy to heat your pool water without excessive degradation of your pool chemicals from strong UV exposure. We love that it's available in various sizes and shapes to fit round, rectangular, and oval pools and has a three-year warranty policy.
This polyethylene pool cover is covered with round air bubbles that are designed to allow solar energy to pass through to your pool water, while reducing evaporation. The cover has an 8-mil thickness, which is thinner than 12-mil or 16-mil pool cover options, so you should handle it accordingly. But the lightweight material of the cover also means it’s a good pick for use on a pool reel, and it’s less of a chore if you have to fold the cover up when not in use. For reference, this version weighs about 20 pounds for a 16 x 32-foot cover, while our pick for the best heavy-duty pool cover weighs about 30 pounds, saving you about 10 pounds of weight that has to be pulled out of the water.
Price at time of publish: $131
Size: 16 x 32 feet | Shape: Rectangle | Thickness: 8 mil | Material: Polyethylene | Weight: 19.8 pounds
Sun2Solar 800 Series Solar Pool Cover
Light blue color to minimize UV effect on pool chemicals
Trim-to-fit your pool size
Size and shape availability varies by retailer
Thinner material may tear more easily
The Sun2Solar 800 Series is an affordable pick for a pool cover that will trap solar energy while keeping out unwanted debris. This 8-mil-thick solar pool cover is thinner than other options but reduces water loss due to evaporation and has a light blue color to protect pool chemicals from intense UV exposure.
Depending on the retailer you shop, you can find this budget solar pool cover in rectangle, round, oval, and square shapes of varying dimensions. As an example of the price point, you’ll spend about $150 for an 18 x 38-foot rectangular cover for an in-ground pool, compared to spending more than $200 for a similarly-sized cover from other brands. The 8-mil thickness may be less durable when compared to thicker covers, so use extra care when pulling it out of the pool to avoid ripping or tearing the material.
If you don’t find your exact dimensions, don’t worry—you can trim the cover to fit your needs without voiding the 3-year warranty. Before you pick up the scissors, keep in mind that most pool covers should have about two inches of overlap, compared to the size of your pool to ensure adequate coverage.
Price at time of publish: $155
Size: 18 x 38 feet | Shape: Rectangle | Thickness: 8 mil | Material: Not Listed | Weight: Not Listed
Blue Wave 14-mil Solar Blanket
Thicker material for better durability
Clear material for maximum solar energy transfer
Doesn’t protect pool chemicals from UV exposure
Water sometimes becomes trapped on top of the thicker material
The Blue Wave 14-mil Solar Blanket is a highly rated solar pool cover that we recommend for rapidly raising your pool temperature. This pick is popular for its durability and effective heat transfer, which is a great feature if you want to extend your pool season by raising water temperatures.
Customers praise this solar pool cover for its ability to raise water temperatures by up to 15 degrees. Of course, your specific results will depend on factors like ambient air temperature and the amount of sun exposure your pool sees each day. Most people who buy this pool cover find that pool temperatures don’t dip as low overnight, making the pool more comfortable for swimming the next day. The clear material doesn’t block as much UV exposure, but that is the price to pay for maximum solar energy transfer. Pay attention to your pool chemistry to ensure that water-quality levels stay in balance while using.
One of the most outstanding features of this clear solar pool cover is its 14-mil thickness. Although it’s heavier to maneuver and fold than thinner solar pool covers, and water sometimes becomes trapped on the surface, it is less prone to ripping or tearing. It can still be trimmed to fit the dimensions of your pool or to suit a freeform or kidney pool shape. It has a six-year warranty period, compared to the usual three-year warranty of budget picks for pool covers.
Price at time of publish: $204
Size: 16 x 32 feet | Shape: Rectangle | Thickness: 14 mil | Material: Not listed | Weight: Not listed
Best UV Resistant
In the Swim Premium Plus Solar Blanket
Aluminized cover to increase heat transfer
Dark surface to minimize changes to pool chemistry
Durable 12-mil material
Cover may retain more heat than it transfers to pool water
Exposure to UV rays can have a negative impact on your pool’s water chemistry, reducing chlorine levels. If you don’t want to compensate by adding more chemicals to your pool water, then look for a dark-colored solar pool cover that will block UV rays from the water below. If that’s your priority, then we recommend the Premium Plus Solar Blanket from In the Swim.
This 12-mil solar pool cover has a blue backing, combined with a black bubble surface. In combination, the aluminized cover minimizes UV exposure while maximizing solar energy transfer to the water below. According to the manufacturer, you can expect up to a 15-degree rise in water temperature, although some people find that the heat is stored in the cover itself or only absorbed by the surface water. Even still, this solar pool cover reduces water loss due to evaporation and keeps your pool’s chemical levels in check.
Price at time of publish: $247
Size: 25 x 38 feet | Shape: Rectangle | Thickness: 12 mil | Material: Not listed | Weight: Not listed
Crystal Blue Extra Heavy-Duty Space Age Solar Pool Cover
Light blue and silver cover to maximize heat transfer and protect pool chemicals
Manufacturer offers ten-year warranty
10-mil thickness to ensure durability and ease of handling
Limited sizes available
Mixed reviews on how effective it is at raising pool temperatures
Solar pool covers come in varying thicknesses that determine how effective the cover is at warming your pool and how durable the cover is as you pull it in and out of the pool. We like the Crystal Blue Extra Heavy-Duty Space Age Solar Pool Cover for a thicker, heavy-duty option that isn’t too cumbersome for regular use.
It has a 10-mil thickness that is more comparable in weight to an 8-mil pool cover but with more durability. The material has a light blue backing to attract solar energy while minimizing UV exposure. The silver surface of the cover features round air bubbles to transfer heat into the water below. Crystal Blue claims that the Extra Heavy-Duty Solar Pool Cover will raise water temperatures up to 15 degrees and some users have found this to be accurate. The effectiveness for your pool will depend on many factors, but it is a durable choice with a ten-year warranty. The biggest challenge may be finding this pool cover in the right size and shape to fit your pool, as the availability is somewhat limited.
Price at time of publish: $249
Size: 18 x 36 feet | Shape: Rectangle | Thickness: 10 mil | Material: Polyethylene | Weight: 37.8 pounds
Midwest Canvas Space Age Solar Blanket
Blue-and-silver material for attracting heat and blocking UV rays
Includes grommets to allow for water to drain from pool cover
Limited sizes available
Grommets are attached after purchase
For a round solar pool cover, our top pick is the Midwest Canvas Space Age Solar Blanket. This option is made of 12-mil resin material and features a blue backing and silver surface with round air bubbles. The blue-and-silver color combination is popular for optimizing heat transfer to the water of your in-ground or above-ground pool while protecting pool chlorine from UV exposure. Size availability varies by retailer and can be limited.
This round solar pool cover includes grommets that allow water to pass through the cover in several locations. While the cover doesn’t arrive with grommets attached, they are self-punching and relatively easy to install after you receive the pool cover. You don’t have to attach the grommets, but doing so makes it easier to drain water from the top of the cover when you’re pulling the cover out of the pool. The grommets allow a small amount of water to seep on top of the cover, which can keep your pool cover in place under light wind. That may be especially helpful for above-ground round pools, where the cover can blow off the pool and into your yard.
Price at time of publish: $180
Size: 18 feet | Shape: Round | Thickness: 12 mil | Material: Resin | Weight: Not Listed
Sun2Solar 1200 Series Rectangle Solar Pool Cover
More durable than 800 series pool covers
Available in clear or light blue
Thickness not specified
No grommets included to allow water to pass through
If you have a rectangular pool, you’ll want to find a solar cover that adequately covers the pool from side to side and end to end. A pool cover that fits over the entire surface of the pool is more effective at trapping heat and reducing water loss due to evaporation. For a rectangular solar pool cover, consider the Sun2Solar 1200 Series. It’s available in light blue or clear resin material, with round air bubbles for transferring solar energy to your pool water.
The 1200 series pool cover is made of a plastic resin material and is thicker than the brand’s 800 series pool covers, resulting in greater durability. That may be especially helpful if your rectangular pool is in-ground, and the cover may be subject to some shuffling or pulling across a concrete pool deck. It can also be rolled onto a pool cover reel—just keep in mind that it may be heavier to roll than an 8-mil cover. It doesn’t include any self-punching grommets like you’ll find on the Midwest Canvas Space Age Solar Blanket. However, these can be added after the fact if you experience the cover blowing around in the wind or find it hard to remove from the pool, due to extra water weight.
Price at time of publish: $160
Size: 15 x 30 feet | Shape: Rectangle | Thickness: Not listed | Material: Resin | Weight: 23 pounds
Natural Chemistry COVERfree Liquid Solar Blanket
Saves the effort of removing and replacing a physical cover
Formula is pH neutral
Application only required once per week
No physical barrier for UV rays or debris
Needs to be added to pool skimmer for best results
One alternative to a removable solar pool cover is a liquid version. This pool water additive creates a liquid "cover" that helps to reduce pool water evaporation. It’s a great option if you lack the time or ability to regularly remove and replace a solar pool cover. We recommend Natural Chemistry Coverfree Liquid Solar Blanket, especially for pools in dry climates where evaporation and heat loss are frequent problems.
To mimic the effect of a typical pool cover, the Coverfree solution works by creating a barrier on the surface of your pool water. It’s pH-neutral, invisible, and safe for swimmers. The best part about this liquid solar pool cover is that it saves the time and hassle associated with removing and replacing a bulky physical pool cover, but keep in mind that it won’t protect your pool from UV rays or debris that may blow into the pool.
Coverfree Liquid Solar Blanket comes in a 32-ounce bottle. You’ll need four ounces of the solution for every 20,000 gallons of pool water. For best results, use it on a weekly basis by adding it to the skimmer while your pool pump is running.
Price at time of publish: $28
Size: Not applicable | Shape: Not applicable | Thickness: Not applicable | Material: Not applicable | Weight: Not applicable
Best for Hot Tubs
Spa Depot Thermo-Float Hot Tub Bubble Cover Floating Spa Blanket
Thick 16-mil material for better heat retention
Trim-to-fit your spa or hot tub
Reduces evaporation up to 95 percent
Not a replacement for a safety cover
Just like for a swimming pool, a solar pool cover helps to maintain the temperature and water level of in-ground spas and hot tubs. The Thermo-Float Spa Blanket is the right pick for the job, since it’s made of a durable 16-mil material for superior thickness and heat retention.
This solar pool cover measures 84 x 84 inches, but can be trimmed to fit the size and shape of your hot tub. The light blue color minimizes the effect of UV rays on water chemistry, while the round bubbles allow for heat transfer to the water underneath the solar cover. Keep in mind that this isn’t a replacement for a hot tub safety cover. Instead, it’s designed to be used on in-ground spas and hot tubs where you’re looking to minimize evaporation (up to 95 percent) and maximize heat retention.
Price at time of publish: $55
Size: 7 x 7 feet | Shape: Square | Thickness: 16 mil | Material: Not Listed | Weight: 4.4 pounds
Our top recommendation for a solar pool cover is the Robelle Heavy-Duty Blue Solar Pool Cover. It has an 8-mil thickness, which keeps it light and maneuverable. The blue tint of the polyethylene material means it's effective at retaining heat while blocking a measure of UV rays, which negatively impact pool chemistry. But if you want to skip the hassle of regularly covering and uncovering your pool, pick Natural Chemistry COVERfree Liquid Solar Blanket. Add the liquid formula to your pool skimmer, and it will increase the surface tension of the water, which reduces evaporation and heat loss.
What to Look for in a Solar Pool Cover
When shopping for a solar pool cover, make sure you have accurate dimensions for your pool available. “You should measure the longest and widest points of your pool to ensure that the solar pool cover completely covers your pool area,” says Jimmie Meece, Brand President of America’s Swimming Pool Company. “If the cover does not completely enclose the water surface, heat will escape.”
You’ll most often find solar pool covers in round, rectangular, oval, and square shapes. Order one that most closely matches your pool’s dimensions, but don’t pick a cover that is too small to cover the surface of the pool. If you can’t find a pool cover that matches the dimensions of your pool, always size up; most covers can be trimmed to fit the size or specific contours of your pool.
The materials of a solar pool cover vary, but all options are non-permeable and designed to trap heat and minimize evaporation. Some of the most common materials for solar pool covers are vinyl, polyethylene, or polypropylene.
- Vinyl solar pool covers are among the most durable types of covers. The thicker material is more rigid, “making them easy for pool owners to easily remove without tearing,” according to Meece.
- Polyethylene solar pool covers are “lightweight and flexible and are effective at transferring heat,” says Meece. He cautions that despite these benefits, they are less durable and may require more frequent replacement than a vinyl solar pool cover.
- Polypropylene solar pool covers are the best option for transferring and retaining heat. Meece says that these covers are very effective, but the downside is that they can be difficult to maneuver, due to their thickness.
The thickness of a solar pool cover is measured in mils, which is not the same as millimeters. A mil is a unit of measurement equal to 0.001 inches. Most solar pool covers are between 6 and 30 mils, according to Meece. “The thicker the cover, the more durable your solar cover will be against sun damage and ripping, however, they will be harder to maneuver,” he says. With that in mind, if you prioritize a lighter pool cover that is easier to remove and replace regularly, then the Robelle Heavy-Duty Blue Solar Pool Cover that measures 8 mils thick may be your best bet, but if you don’t mind a little extra weight or have a helping hand for uncovering your pool, then you might choose a thicker pool cover like the Midwest Canvas Space Age Solar Blanket, which is a 12-mil-thick cover.
Color and Air Bubbles
Solar pool covers are typically either clear, light blue, silver, or a dark blue or black. Color isn’t an aesthetic choice; instead, the color of the cover determines how effective the cover is at transferring heat and blocking UV rays. In terms of heat transfer, Meece says that “clear solar pool covers are the most effective.” He points out that the clear material allows the sun’s rays to easily penetrate the water underneath the cover, but there’s a drawback. “They do not block UV rays that can break down your chlorine.” As a result, you may need to add chemicals to your pool water more frequently. Even still, it’s a great option for transferring heat to your pool and a key reason why the Blue Wave 14-mil Solar Blanket is one of the top-rated options for a solar pool cover.
Air bubbles are frequently found on solar pool covers. The “purpose of air bubbles is to trap heat while simultaneously insulating the heat at night when the sun goes down,” says Meece.
How long does it take for a pool to warm up with a solar cover?
Depending on the time of day and the amount of sun exposure, “a solar pool cover can heat your water by a few degrees in a matter of approximately six hours,” according to Meece. He adds that use of a pool cover at night will also help keep your pool temperature from “drastically dropping on chilly nights by insulating the heat collected during the day.” That means you can enjoy a more consistent water temperature for your pool.
Do solar covers increase algae?
A solar pool cover can create favorable conditions for algae growth. “Since solar pool covers keep your pool warm and prevent evaporation, algae may grow more quickly than normal,” says Meece. “Staying on top of maintenance needs, including regularly removing organic matter and keeping your pool chemicals balanced, will combat this.”
How many degrees does a solar cover add?
Some people find that a solar pool cover raises the water temperature of their pool up to 10 degrees, but it’s important to remember that the key function of a solar pool cover is to retain the heat in your pool. Meece says that, depending on your pool size, “it’s likely a solar cover will only heat the top 6 inches of water and will not raise the water temperature of your entire pool.”
Why Trust The Spruce?
Erica Puisis has been covering the best products for outdoor and indoor living at The Spruce since 2017. Her research and areas of expertise have included pool heaters, cleaners, and water testing equipment. To find the best options for this essential pool accessory, she considered the thickness of each solar cover, its ability to retain heat, block UV rays, or provide passive heating for pool water, and the length of any warranty periods.
Puisis spoke to Jimmie Meece, Brand President of America’s Swimming Pool Company. He provided insight on the most common materials for solar pool covers and how to size a pool cover appropriately for maximum effectiveness.