Ever feel your hot tub turns into an ice bath on a cold morning? A solar blanket can lock in heat, cut your heater bill, and keep water from evaporating. In this roundup we break down the price, thickness, fit and real‑world performance of the most popular blankets on the market today. By the end you’ll know which blanket gives the best bang for your buck and how to match it to your tub size.
1. SunHeater Solar Blanket 8mil , Best Budget Pick
SunHeater offers a thin‑but‑effective 8 mil bubble blanket that fits most standard hot tubs. At under $60 it’s the cheapest option that still traps enough solar heat to raise water temperature by 5‑10°F on sunny days. The material is low‑density polyethylene with tiny air bubbles that float on the surface. Because it’s light, one person can roll it out and fold it back without help.
Installation is simple: lay the blanket flat, smooth out air pockets, and tuck the edges under the tub lip. If your tub is a bit larger, you can trim the edges with scissors , the bubble side stays down. The cover works best when you keep it on overnight; it blocks up to 90% of evaporation, which means you use less chemicals.
Pros: cheap, easy to handle, good heat gain for price. Cons: thinner film can tear after a few seasons, less UV protection.
Customers who bought SunHeater say they notice a warmer soak within an hour of sunrise. The blanket’s low weight also means you can lift it off quickly if a sudden storm rolls in.
2. Solar Comfort Premium 12mil , Best for Durability
Solar Comfort’s 12 mil blanket adds a sturdier layer of plastic that resists punctures and UV fading. The extra mil gives a noticeable weight, so you may need two people to roll it out on a larger tub. The bubbles are larger, which helps trap more heat; users report a 7‑12°F rise after a sunny day.
According to Wikipedia’s solar blanket entry, thicker blankets retain heat longer because they reduce convection losses. Solar Comfort follows that principle with a UV‑inhibitor coating that lasts three years before yellowing.
Installation steps: 1) lay the blanket flat, 2) smooth bubbles toward water, 3) secure the edges with the supplied elastic cords. The cords wrap around the tub lip and keep the cover from blowing away in wind.
Pros: strong, UV‑stable, good heat gain. Cons: heavier, higher price ($120‑$150).
SunHeater is the budget option, but if you’re willing to spend a bit more for durability, Solar Comfort is the logical next step.
3. SmartPool S200 Solar Blanket , Best for Small Tubs
SmartPool’s S200 is sized for tubs under 6 ft in diameter. At 8 mil thickness it’s lightweight, and its dimensions (5 ft × 5 ft) fit snugly around compact hot tubs. The cover includes a quick‑clip system that locks onto the tub’s lip, making removal a one‑hand job.
Because the blanket is small, it folds into a compact roll that fits in a standard storage bag. This is handy for homeowners who need to stow the cover during winter.
Heat retention is modest , about a 4‑6°F rise , but the main benefit for small tubs is the reduction in evaporation, which can be as high as 80% in dry climates.
Pros: perfect fit for small tubs, easy storage, affordable ($70‑$80). Cons: not suitable for larger tubs, lower heat gain.
Imagine a weekend getaway where you only have a two‑person spa. The S200 slides on in seconds, keeps the water warm enough for a quick dip, and you can tuck it away when the season ends.
4. Blue Wave Solar Blanket 10mil , Best Value Mid‑Range
Blue Wave’s 10 mil blanket hits the sweet spot between price and performance. It’s thicker than an 8 mil budget model but lighter than a 12 mil heavy‑duty one. The blanket measures 7 ft × 8 ft, covering most rectangular tubs.
Manufacturers claim up to a 15°F temperature boost on sunny days. Real‑world tests from owners show a typical rise of 8‑10°F, which is enough to cut heating cycles by half.
Installation tip: lay the blanket flat, then fold the edges over the tub lip and use the attached tie‑downs to lock it in place. The ties keep the blanket from being blown off by gusts.
Pros: solid heat gain, good UV protection, reasonable price ($110‑$130). Cons: a bit heavier to lift alone.
One user shared that after using the Blue Wave blanket for a season, their monthly heating bill dropped by nearly 30%. The thicker film also resisted tearing even after a summer of high winds.
5. Aqua Defender Solar Cover 14mil , Best Heavy‑Duty
Aqua Defender’s 14 mil blanket is built for owners who want a rugged, long‑lasting solution. The thick film can handle wind, debris and occasional foot traffic without ripping.
Because of its weight, you’ll likely need two people to position it on a large tub. The blanket comes with reinforced grommets that you can tie to a small anchor system if you live in a windy area.
Heat gain is impressive , up to a 12°F rise on bright days , and evaporation drops by 95%, which means less water loss and lower chemical use.
Pros: very durable, excellent heat retention, strong wind resistance. Cons: pricey ($180‑$210), heavy to handle.
In desert climates like Palm Desert, the extra thickness helps keep water from heating up too fast during the day while still protecting against night‑time heat loss.
6. In The Swim Solar Blanket 8mil , Best for Round Tubs
In The Swim’s 8 mil round blanket is cut to a perfect 12‑foot diameter, ideal for standard circular hot tubs. The bubble side faces down, and the clear side lets sunlight pass through while the bubbles trap heat.
Owners love the simple trim‑to‑fit method: you can cut a few inches off the edge with scissors if your tub is slightly smaller. The blanket folds neatly into a half‑roll for storage.
Heat increase averages 5‑8°F, enough to keep the water comfortable after sunset. Evaporation reduction is around 90%.
Pros: perfect round fit, easy to trim, affordable ($85‑$95). Cons: thinner film can wear faster in harsh sun.
One reviewer mentioned using the blanket on a 21‑ft round spa; after trimming, the cover sat flush and stayed in place even during a windy night.
7. SolarPro Bubble Blanket 12mil , Best Heat Retention
SolarPro’s 12 mil bubble blanket is engineered for maximum heat capture. The larger air bubbles create a thicker insulating layer, which translates to a higher temperature rise , often 10‑12°F on a clear day.
The blanket includes a reinforced edge that slides over the tub lip, preventing the cover from lifting. The material is UV‑stabilized, so it won’t become brittle after a few seasons.
Because of its thickness, the blanket weighs more than an 8 mil model, so you may need two hands to position it. However, the added weight also means it stays put during gusty evenings.
Pros: strong heat gain, UV‑stable, secure edge design. Cons: heavier, higher cost ($140‑$160).
Imagine a winter night in the Coachella Valley. With SolarPro on, the water stays warm enough that you can skip the heater for a few hours, saving electricity.
8. Sun2Solar Blue 8mil , Best Clear Bubble Blanket
Sun2Solar’s blue‑tinted 8 mil blanket adds a subtle color that blends with pool water while still allowing sunlight to pass. The tint can help reduce glare for night‑time swimmers.
The blanket measures 8 ft × 8 ft, fitting most square or slightly rectangular tubs. It includes a built‑in roller that lets you roll the cover on and off with one hand.
Heat gain is similar to other 8 mil blankets , around 5°F , but the roller system makes daily use effortless, encouraging owners to keep the blanket on more often.
Pros: easy roller system, attractive blue hue, lightweight. Cons: modest heat gain, roller can wear over years.
Owners report that the roller saves time, so they rarely forget to put the blanket back on after a night swim.
9. SmartPool S400 Solar Blanket , Best for Large Tubs
SmartPool’s S400 is designed for hot tubs up to 30,000 gallons. It comes as a two‑piece set that you lay side by side to cover a large surface area. Each piece is 12 mil thick, providing strong heat retention.
The blanket includes a patented “SolarPill” dispensing system that releases a tiny amount of water‑preserving chemicals each day. While the pills don’t raise temperature dramatically, they reduce evaporation, which indirectly helps keep the water warm.
Installation requires aligning the two pieces and securing them with the included clips. Because of its size, you’ll likely need help to unfold and position it.
Pros: covers large tubs, includes evaporation‑reduction pills, solid heat gain. Cons: complex setup, higher price ($250‑$300).
In a large spa used for weekend parties, the S400 can cut heating time by 30%, letting guests enjoy warm water sooner.
10. PoolMate Solar Blanket 10mil , Best with UV Protection
PoolMate adds a UV‑blocking additive to its 10 mil film, which helps prevent the plastic from yellowing after years of sun exposure. The blanket is sized 8 ft × 10 ft, making it a good fit for rectangular tubs.
Heat gain is about 8°F on a sunny day, and evaporation drops by 92%. The UV protection also means the blanket lasts longer without cracking.
Installation is straightforward: lay the blanket flat, tuck the edges under the tub lip, and secure with the supplied straps.
Pros: UV protection, good heat gain, moderate weight. Cons: not the thickest option, price around $130.
For homeowners who leave their tub uncovered for many months, the UV blocker can save the hassle of replacing the blanket every few years.
11. Solar‑Cover 8mil Budget Blanket , Best Under $50
The Solar‑Cover 8 mil model is the most affordable blanket you can find on major retail sites. It’s a thin sheet that still creates a bubble layer to trap heat.
Because it’s cheap, the material is basic and may develop small tears after a season. Still, it reduces evaporation by about 80% and can add 3‑5°F of warmth.
It comes in a 6 ft × 7 ft size, suitable for smaller tubs. The blanket folds easily and can be stored in a small bag.
Pros: extremely low cost, easy to handle. Cons: limited durability, modest heat gain.
Perfect for a secondary spa you only use a few times a year, where you don’t want to spend much.
12. SolarSun Premium 16mil , Best Professional Grade
SolarSun’s 16 mil premium blanket is aimed at commercial spas that run daily. The extra thickness adds weight and durability, allowing it to survive heavy foot traffic and frequent handling.
Heat gain can reach 15°F on a bright day, and evaporation drops by up to 96%. The blanket also includes a reinforced edge that clips onto a motorized reel, making it easy to roll up.
Because it’s heavy, you’ll need a motorized reel or at least two people to position it.
Pros: top‑tier heat retention, compatible with motorized reels, built for heavy use. Cons: high price ($300+), requires extra equipment.
Many spas in resorts use SolarSun blankets because the ROI comes from reduced heating costs over many seasons.
13. Blue Wave Bubble Wrap 8mil , Best Lightweight Option
Blue Wave’s 8 mil bubble wrap is marketed as a lightweight, easy‑to‑handle cover. It’s thin enough for one‑person use but still creates a bubble barrier.
Heat gain is modest (4‑6°F), but the main selling point is its ease of storage , it folds into a small bundle that fits in a garage shelf.
It’s priced around $40, making it a good starter blanket for new tub owners.
Pros: very light, cheap, simple to trim. Cons: limited durability, lower heat gain.
Homeowners who only use their spa in summer may find this enough to keep water warm for a few hours after sunset.
14. AquaTherm Solar Blanket 12mil , Best Overall Value
AquaTherm’s 12 mil blanket strikes a balance between cost and performance. It’s thicker than budget options but lighter than heavy‑duty models. The blanket measures 9 ft × 11 ft, covering most rectangular hot tubs.
Heat gain averages 9°F, and evaporation drops by 93%. The company offers a five‑year limited warranty, which is longer than many competitors.
Installation involves laying the blanket, aligning the built‑in grommets, and fastening the supplied straps. The grommets make it easy to tie the blanket down on windy days.
Pros: solid heat gain, long warranty, reasonable price ($150‑$170). Cons: medium weight, may need two people for large tubs.
Overall, AquaTherm gives you a dependable blanket without breaking the bank.
Price Comparison Table: Best Hot Tub Solar Blankets
How to Choose the Right Hot Tub Solar Blanket for Your Budget
Start by measuring your tub’s length, width and shape. Write down the dimensions and compare them to each product’s size chart. If your tub is round, look for a blanket listed as “round” to avoid awkward cuts.
Next, decide how much heat you need. Thicker blankets (12‑16 mil) keep water warmer longer but cost more and are heavier. For occasional use, an 8 mil option may be enough.
Check the UV‑protection rating. In sunny deserts, a UV‑stable cover will last longer and won’t turn yellow.
Finally, factor in the total cost of ownership. A higher‑priced blanket that saves $70 on heating each month can pay for itself in under a year. The U.S. Department of Energy notes that insulating a hot tub can cut heating energy use by up to 70%.
For a quick decision, use this simple checklist:
- Measure tub size.
- Pick thickness based on climate and usage.
- Confirm UV protection if you’re in a sunny area.
- Compare price vs expected energy savings.
Our internal Hot Tub Buying Guide walks you through the whole process, from sizing to installation.
FAQ
What size solar blanket do I need for a 7‑ft rectangular tub?
Measure the length and width of your tub, then add a few inches to each side so the blanket can fold over the lip. A 7 ft × 8 ft blanket works well for most 7‑ft rectangular tubs, giving enough overlap to secure the edges without excessive excess material.
Will a solar blanket protect my tub from debris?
Yes. The bubble surface sits on top of the water and catches leaves, insects and dust. While it won’t stop large objects like a falling branch, it does keep most everyday debris out, which means you’ll spend less time cleaning the water.
How much can I expect my heating bill to drop?
Studies from the U.S. Department of Energy show that a well‑fitted solar blanket can cut heating energy use by 50‑70%. For a typical 4‑hour nightly soak, you might see a $30‑$50 monthly saving, depending on local electricity rates.
Can I use a solar blanket year‑round?
You can leave the blanket on in mild winters, but in freezing climates you’ll want to remove it to avoid ice buildup. In desert areas, many owners keep the blanket on year‑round because the sun still provides warmth on cooler days.
How do I store the blanket when not in use?
Roll the blanket loosely, don’t fold, to avoid creasing the bubbles. Store it in a dry, shaded area, such as a garage shelf or a storage box. Keeping it out of direct sunlight prolongs the UV‑inhibitor coating.
Is it worth buying a motorized reel?
If you have a large or heavy blanket, a motorized reel saves effort. A one‑button roll‑up system encourages owners to put the cover on every night, which maximizes heat retention and energy savings.
Conclusion
Choosing the right hot tub solar blanket comes down to size, thickness, UV protection and budget. SunHeater wins on price, while Aqua Defender and SolarSun lead on durability for heavy‑use settings. Mid‑range picks like Blue Wave and AquaTherm give solid heat gain without a huge spend. Remember to measure your tub, think about how often you’ll use the blanket, and weigh the long‑term energy savings against the upfront cost.
Keeping water warm not only makes your soak more enjoyable, it also cuts heating bills and reduces water loss. With the right blanket you’ll get more soak time and less maintenance. Ready to upgrade your spa experience?Explore Luxury Hot Tubs’ full hot‑tub guide to pair your new blanket with an energy‑efficient spa that fits your desert backyard.