4 Best Knee Pillows in 2026: Tested and Approved

How we test pillows

We started our process by researching the market. Which pillows are popular and why? Which have the best customer reviews, and are the reviews legitimate? We also held a November 2025 sleep focus group with people between the ages of 51 and 69 to dig into what older adults want in a new mattress and pillow. Finally, in March 2026 we ran a sleep accessories survey of 300 adults ages 50 and older to gain a broader perspective on what matters when buying a new pillow. After completing our research, reviewing the results of the surveys and focus groups, and speaking with medical experts, we narrowed our list of pillows to test.

To identify each pillow’s strengths and weaknesses, we conducted controlled tests to assess such attributes as sinkage, ease of care and temperature regulation. We then recruited older adult testers to give us their unbiased feedback. They answered questions like: How easy is it to adjust the pillow’s height or firmness? Does your spine feel well aligned? Did the pillow warm up? The models that excelled in our tests made our list of the best knee pillows.

For more details on our process, see our mattress and sleep accessories testing methodology.

How to choose the best knee pillow

Based on our test results, input from older adults and insights from medical professionals, we found the following factors to be most important in selecting the right knee pillow.

Pillow loft (height)

A knee pillow’s loft — also known as its height or how thick it is — makes a big difference.

To gauge the right height, use the width of your hips as a starting point, says Ashley Katzenback, a doctor of physical therapy in Plymouth, Massachusetts. “The wider your hips are in relation to your spine and knees, the thicker the pillow you need,” she says. That way, your hips and knees are in a more neutral position, which tends to make you feel most comfortable.

For side sleepers, the pillow “should be thick enough to keep the top leg from dropping inward,” says Dr. Omar Rahman, a board-certified orthopedic surgeon and sports medicine specialist at DISC Marina del Rey in California. “This takes stress off the hip and the [lower] spine and is probably the single most impactful change a side sleeper can make.” 

Finding the right height may take some trial and error. If you’re not sure what size you need, an adjustable model like the Coop Adjustable Knee Pillow gives you the ability to try different thicknesses to see what works.

Temperature regulation

Many older adults don’t like using a knee pillow since it can retain heat, says Katzenback, the physical therapist in Massachusetts. The more pillows you sleep with, the more potential for increasing the temperature. While many of the pillows we tested were not effective at limiting heat buildup, some were — including the Sleep Number Knee Pillow. For hot sleepers or those experiencing hot flashes, a pillow with strong cooling capabilities could make a difference.

To learn about more cooling options, read our reviews of the best cooling pillows and best cooling mattresses.

Trial period

When you buy a pillow with a trial period, you can try it out at home for a limited time and return it if it doesn’t work for you. While the return may be free, some companies charge a shipping or restocking fee. 

Pillows don’t always come with trial periods, but most of the brands in our roundup offer at least 30 nights. Tempur-Pedic, which has a no-return policy, is the only exception. On the other hand, Coop and Sleep Number offer the most generous window: 100 nights.

How do I position a knee pillow?

The ideal arrangement depends on whether you sleep on your side or your back. But don’t worry too much about changing positions at night. It’s natural to toss and turn when you sleep, says Aime Maranan, a physical therapist in Evanston, Illinois. “As long as you maintain a position that your body can tolerate and allows for a good night's sleep, that is what matters,” she says.

Positioning for side sleepers

Side sleepers seeking relief from back or hip pain could benefit from placing a knee pillow between their thighs so their knees are hip-width apart. This places the spine and hips in a more neutral position.

Rahman, the orthopedic surgeon in California says he often sees older adult patients in his practice who develop knee pain from side sleeping without a knee pillow to prevent the top leg from dropping inward and twisting the knee.

Positioning for back sleepers

Back sleepers can alleviate back or hip pain by placing a knee pillow under both legs. This relaxes the hips, which helps release pressure from the lower back.

Do knee pillows help with pain relief?

They might. The added support can offload tension in the hamstrings (the muscles at the back of the knee), as well as the nerves running down the back of the legs to the feet, says Dr. Rahul Shah, an orthopedic spine and neck surgeon in Philadelphia.

But the experts we spoke with concur that the outcome depends on what’s causing the pain. In their experience, older adults who benefit most from knee pillows for pain relief include people with:

• Spine conditions, like lumbar stenosis 
• Osteoarthritis in the knee or hip
• Muscle or soft tissue irritation in the hip or back
• Some nerve-related issues, like sciatica

If a knee pillow doesn’t seem to work, Shah says to first try swapping it for one with a different height to see if that makes a difference. If you’re still uncomfortable, Katzenback says an old mattress that needs replacing could be the culprit. If you suspect the same, check out our reviews of the best mattress for back pain and the best mattress for sciatica.

Otherwise, the experts we consulted recommend seeing a doctor or physical therapist to discuss your symptoms, determine the root cause of your discomfort and find strategies for relief.

How much do the best knee pillows cost?

Our picks cost between $29.99 and $113.33. We rated the Sleep Number Knee Pillow the best value because it’s the most affordably priced at $29.99. The Helix Side Sleeper Knee Pillow is the most expensive at $113.33, which may be a worthy investment for dedicated side sleepers because of its stability strap.

The companies on this list often offer discounts throughout the year, particularly around holidays.

FAQs

How well do knee pillows work?

It depends on what your needs are and how well it fits your proportions. Based on our testing results and conversations with medical experts, a knee pillow may help ease pressure on your back and hips. But we recommend speaking with a health care provider, like a physical therapist to discuss whether you would benefit from one.

What pillow is best for knees?

The right pillow for you depends on your sleeping position and physique, the structural support you need and the shape, firmness and materials of the pillow. We found the Coop Adjustable Knee Pillow — a firm foam model shaped to fit between the thighs — to be best overall. But a regular bed pillow is a good place to start and may work just as well, says Ashley Katzenback, the doctor of physical therapy on Cape Cod.

How often should a knee pillow be replaced?

Experts recommend replacing your pillow every two years. With wear and tear, the foam compresses, loses its shape and provides less support. If it shows noticeable sagging, it’s time for a new one.

Questions or feedback? Email us at AARPSmartPicks@aarp.org.