Best Mattresses

Eight Sleep Pod 3 Cover Review: The Coolest Solution for Hot Sleepers


This story is part of Sleep Awareness Month 2024, CNET’s deep dive into how sleep impacts your overall health and why it’s crucial to all aspects of life.

Switching to lighter bedding can only do so much when you’re already unbearably hot. But there’s a better solution out there. If you follow the wellness news cycle or health influencers like Andrew Huberman, you might already be familiar with the brand Eight Sleep. I’ve tested numerous cooling sheets, cooling pillows, cooling comforters and cooling mattresses. Yet, none of those products come close to the icy feel of Eight Sleep.

I tried the Eight Sleep Pod 3 Cover for one month. It cooled me down and tracked my health vitals. Here’s how I concluded that the Eight Sleep Pod cover saved me more restful sleep.

Eight Sleep offers two models. The Pod 2 is the older model and the Pod 3 cover is the newest. This latest version includes a new design to increase the comfort. Eight Sleep sent me the Pod 3 to test, but this didn’t sway my opinion nor guarantee a review. These are my honest thoughts.

The Eight Sleep Pod is a temperature-controlled mattress cover that connects to a sleek tank of water beside the bed. Then, the cover’s embedded coils cycle water throughout the mattress. Based on your preferences inputted into Eight Sleep’s app, the Pod will automatically warm or cool your side. If you sleep with a partner, you may choose to have a warm half while they might have a cool side. The Pod warms and cools you throughout the night, mimicking the body’s natural temperature cycle so that you are at the right temperature for each sleep stage. The goal is to increase the time spent in deep or REM sleep.

The stand-out features of the Eight Sleep Pod 3 include:

Before testing, I was skeptical of the Pod. I knew how it worked; I just didn’t know how well. Eight Sleep sounds great in theory — you can set the Pod to as high as 110 degrees Fahrenheit and as low as 55 degrees — but that wouldn’t matter if you can’t feel the temperature from under your sheets. I had to examine this claim.

The Eight Sleep Pod 3 cover doesn’t disappoint: Its temperature control is impressive. Even after adding sheets and a comforter to my bed, the mattress can get uncomfortably cold and unbearably hot at the maximum settings. I never had to set my Pod as low as it can go because just three or four notches is enough. Even then, I was wondering if I was truly a hot sleeper because that was too cold for me.

My boyfriend, on the other side of the bed, set his side of the cover to -6 (-1 is the least cold, -10 is the coldest). This meant that before he got into bed each night, his side was icy. After a few nights of messing around with my starting temperature, I found I liked getting into a warm bed first but needed to be cooled in the middle of the night when I was hottest. I set my side to +3 (+1 is the least warm, +10 is the hottest).

Each Pod cover collaborates with Autopilot — the system that automatically warms and cools you throughout the night. This software isn’t included in the final price; you need to buy a subscription for it, and you can’t buy the Pod without it. While the Standard Autopilot is around $12 a month, it’s also impressive and, honestly, it’s one of the biggest selling points for me.

While you can set your Pod to a certain temperature at bedtime, Autopilot can find the best temperatures to warm and cool you to in each stage of sleep. For example, while I start each night at +3, the pod cools off to a neutral 0 in the early stages of sleep, then drops to a -1 in later stages before slowly warming up to +6 to wake me up. By the time my alarm goes off, my bed is so hot that I don’t want to stay in for a minute longer.

This brings me to another standout feature. The thermal alarm is a great way to gradually wake you. If you aren’t a hot sleeper, you can opt to set the Pod to wake you up to an icy, cold mattress — whatever is the exact opposite of your sleeping preferences. Anything that will push you out of the bed the fastest will work.

You can also set a vibrating alarm. This means your side of the bed will either be too hot or too cold, and it will vibrate to gradually wake you up.

Eight Sleep is known for its sleep and health tracking. The app reports how well you stick to your bedtime routine, the time spent asleep, the sleep quality, the amount of time spent in each sleep stage and your sleep latency (time spent falling asleep and time getting up). Each night you receive an overall Sleep Fitness score, which could be anywhere from 0 to 100.

Both Pod models also track your heart rate, heart rate variability and breath rate. If you’re unsure about a metric, educational material is available for each. The app will alert you if there are changes in your health vitals over time. If you don’t want to wear a sleep or health tracker at night, this is a nice feature.

The Pod 3 arrived in a heavy box that required extra help to transport into my apartment, but getting it out of the box was easy. One half of the box contained the pod cover, and the other half was the Hub, also known as the water tank. Once my boyfriend and I had taken the Pod 3 Cover out of the box, we took the original bedding off our bed and pulled the cover over the bare mattress. The app gave us step-by-step visual instructions that made this part a breeze.

We then answered a few preference questions on the app, choosing the temperature we wanted the bed to be when we first got in it, our bedtime and the time we wanted our morning alarms. After, we added water and hydrogen peroxide into the Hub. The next step is known as Priming, and it took the longest.

During Priming, the Pod fills the coils and cycles the water for the first time. Priming took two to three cycles, and each step was around 45 minutes. After about an hour and a half, we checked the mattress, and it hadn’t cooled at all. The Hub also hadn’t taken any of the water.

We worried we had done something wrong and told the Pod to prime again. But by the time it was halfway through its second Priming, it was time for bed. We canceled the second cycle and went to sleep. Be aware that Priming will take a long time, and you may have to do it more than once.

The next day, we changed the water, added more hydrogen peroxide (Eight Sleep recommends adding this during the Priming process) and tried Priming it a third time. Thankfully, it worked that time, and we were ready to test the temperature settings.

I was concerned that the Pod would be noisy. But it’s only slightly loud during the Priming process. If you listen closely, you can hear the water rushing through the coils, and the Hub makes a low humming sound. It’s quiet enough that an overhead fan can drown it out. Besides the Priming process, I don’t hear the Eight Sleep Pod at all.

While there’s a learning curve to the Eight Sleep Pod Cover, as I described above, once I got the hang of it and found the right starting temperature setting, I started seeing small improvements in my sleep. Here’s the data I have to prove it.

Pictured to the right is my sleep data on the Eight Sleep app from Jan. 23. This was about one week after I first started using the Pod consistently. In the chart, the top five orange lines indicate instances where I was waking up, and the bottom four purple lines indicate deep sleep.

Flash to a month later; the next screenshot of sleep data is from Feb. 21. While the time I spent asleep is about the same, there’s a difference in the time I spent awake. The only orange line indicates that I was awake only before falling asleep.

While this isn’t a dramatic shift, it’s there. Especially with sleep, small changes over time add up to a lot. On top of increasing deep and REM sleep durations and lessening wake periods, it helped me go to bed and wake up at the same time.

However, my biggest testament to how I enjoy the Eight Sleep Pod Cover is how I miss it when I’m gone. During this trial period, I was out of town for a wedding. Instead of having my Eight Sleep, I had to suffer a bare hotel mattress. I admit, now, I’m spoiled, and the Pod might have ruined other mattresses for me forever (in the best way possible).

In addition to the price and the noise during the Priming sessions, the Eight Sleep Pod 3 Cover has a few drawbacks to keep in mind. Before adding to your cart, know that these downsides might be deal breakers.

Set-up: The set-up process can be frustrating. While the instructions were helpful, and the app is great, I wasn’t prepared for how long it would take. Also, I had to Prime the Pod multiple times since the Hub wasn’t taking the water.

Mattress firmness: Another gripe I have with this cover is how it makes my mattress feel. My boyfriend and I have a Casper memory foam mattress, and I like that it’s very neutral in terms of firmness — it isn’t too soft or too firm. However, the Pod Cover definitely adds firmness to the mattress. While I wouldn’t say it would turn a soft mattress firm, it’s a difference that I immediately felt.

Feel the coils: In addition to the firmness of the mattress, the coils of the Pod can be slightly felt when you are lying down. I did eventually get used to the feel, but it’s a little jarring at first. Thankfully, the coils aren’t painful by any means. I’ve never felt them jetting into my hip when I’m on my side. However, for the price, this shouldn’t be an issue. I wish you weren’t able to feel the coils at all.

The biggest drawback to the Eight Sleep Pod is the price. To compare, my favorite cooling mattress — the Brooklyn Bedding Aurora Luxe — is around $1,865 for a queen size. However, when it’s on sale, it is under $1,400. At that price, the Pod Cover 3 is almost $800 more than a brand-new mattress. Remember that the software, called Autopilot, is an added subscription that you need to purchase on top of the overall price.

The Pod 2 and Pod 3 fit mattresses up to 10 to 11 inches deep. The Pod 3 with PerfectFit can fit all beds and has increased comfort. For this review, I tested the Pod 3, and it still fits over my Casper mattress.

After sleeping on the Eight Sleep Pod 3 Cover for a month, my answer to whether it’s worth the price is mixed. Yes, I do think it works, and it’s a great investment for someone who wants to optimize their sleep routine. However, it costs more than a brand-new mattress, and that’s a huge aspect to consider.

“I highly recommend the Eight Sleep Pod 3 Cover,” said my boyfriend, Bryce Cole, who also tested this product for a month. “As a hot sleeper, the Eight Sleep Pod made significant improvements to my sleep where traditional cooling methods could not. If money is not an issue, this is an obvious purchase for anyone who cares about their sleep,” Cole said.

Putting the price aside, Eight Sleep is a testament to the recent advances in sleep technology. Sleep is a fascinating topic that’s readily being explored by scientists, engineers and the everyday-person alike. It’s clear that sleep is crucial to every part of our lives, and the intersection of sleep and technology is only going up from here.

You should try the Eight Sleep Pod Cover if: