Eight Sleep Pod 3 Cover review

This temperature controlled smart mattress cover delivers great, if expensive, sleep

Eight Sleep Pod 3 Cover
(Image: © Future)

TechRadar Verdict

After 8 weeks of testing, we can safely say that the Eight Sleep Pod 3 cover is a great sleep aid with some brilliant smart functionality for heating and cooling. The tracking is top notch but the Pod 3 does come with some caveats. It’s very expensive and you’ll definitely want to add a monthly 8+ Pro subscription for the Autopilot functionality.


  • +

    Incredible heating and cooling

  • +

    Reactive smart tracking

  • +

    Intuitive app

  • +

    Two individual sleep zones


  • -

    Prohibitive cost

  • -

    You’ll want the monthly subscription

  • -

    Base unit requires floor space

  • -

    Changes bed temperature if its off

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Eight Sleep Pod 3 Cover review in brief

The Eight Sleep Pod 3 Cover feels a lot like the sci-fi future of heated mattress toppers. If the number didn’t give it away, snooze specific company Eight Sleep has worked through multiple generations of their Pod Cover, which was created specifically as an option to upgrade your own mattress instead of having to buy the Eight Sleep version.

Instead of electric elements, the Pod 3 Cover uses water from a Nespresso machine-sized base unit which means it has the power to both heat and cool. It goes several steps further than most of today's best cooling mattresses – this isn’t just a case of switching between hot or cold depending on the season. Using the essential connected app, the Eight Sleep Pod 3 Cover can be set between 12C and up to an incredible 43C. Why you would need this when we didn’t need to go over the +4 warm option (on a dial that goes up to +10) even when it was -10C outside, we don’t know, but the choice is there, which we appreciate. Even better is that it’s dual sided, so your partner doesn’t have to endure your preferences and can happily set their own. 

Setting a bedtime on the Eight Sleep app means that the Pod 3 will start warming up from an hour before, to make sure that your mattress is ready for you when you clamber in. Once you have set a favourite starting temperature, this feels like sinking into a warm cosy bath every single night and can’t be underestimated as a true joy.  

Like all of the best mattress toppers, the Pod 3 fits over your existing mattress, but unlike those, as well as heating and cooling, it’s also taking aim at the best sleep trackers. Thanks to swathes of sensors, the Pod 3 Cover tracks not just your heart rate and tosses and turns, but the time it takes you to get to sleep, how long you’re sleeping for, and even how long it takes you to drag yourself out of bed in the morning. And it really works. There’s nothing like an app attacking you with a 25% sleep rating as you drink your morning coffee after a night at the pub and a particularly early start. ‘Your heart rate dropped late. Some reasons could be eating or drinking alcohol closer to bed…’ Thanks, Eight Sleep. We’re aware

Eight Sleep Pod 3 Cover

(Image credit: Future)

But the Pod 3 doesn’t just use this information to beat you smugly over the head the next day, it also uses its biometric sensors for its Autopilot function. This is a feature that means the cover changes the temperature on the fly to actively keep you asleep. Thanks to the base unit CPU being hooked up to Wi-Fi, the Pod 3 knows your location and real time temperature. It learns your temperature preferences and then adjusts the temperature overnight to create your own personal microclimate. Different sleep stages require different temperatures, so the Pod 3 adjusts accordingly. 

Eight Sleep Pod 3 Cover specs

Sizes: US Full, US Queen, US King, California King, UK Double, UK King, UK Super King   

Trial period: 30 nights 

There are a few key points to make on this. Autopilot is only available with the monthly 8+ Pro Membership which costs $19 in the US and £14 in the UK. It’s also nigh-on necessary if you don’t want to wake up baking in the middle of the night after deciding you wanted to go to sleep set to ‘toasty.’ Also, the Pod 3 takes a full week to ‘learn’ your temperature preferences. Quite honestly, this was relatively stressful over this time as we woke up sweltering and had to grab our phone to turn things down.

However the change now that the Pod 3 has learned is remarkable. There’s still the odd night where things get too warm but we can see full nights with no wake ups and the app shows you on your sleep graph where changes were made and how many factors were taken into consideration for this small tweak. It took a little work but the Pod 3 now feels like a cosy revelation and has only improved over the extended review period. There are days where we genuinely recognise feeling much better rested.       

Importantly, for all of the tech crammed in here, the Pod 3 Cover maintains the comfort of your mattress. In fact, the only problem is if you get into bed without it preheating in winter, the room temperature will have had an effect on how cool your mattress feels as it’s effectively laced with water. This was especially evident during our testing period which has featured the coldest December since 2010 in the UK.  Given these recent temperatures we have only truly managed to appreciate the heating but the potential for summer cooling is evident. Temporarily switching to cold is a delightfully chilling experience that will clearly make sweltering summer nights far easier.              

Eight Sleep Pod 3 Cover review: Price and release date

  •  Released July 2022
  • Optional monthly 8+ Pro subscription at $19/£14 per month 

There’s no denying it. For a piece of sleep tech the Eight Sleep Pod 3 cover is very expensive. Even the most luxurious of mattress toppers seem positively affordable in comparison but there are a number of big differences. First off, it’s important to note that even though there are cooling options available, none of these are active. The Pod 3’s power to cool and warm at specific temperatures works exceptionally well to balance out your body temperature at any given moment. Layer in the smart tracking functionality and you can actually happily leave your Apple Watch charging on the nightstand, these biometrics have you covered.  

The Pod 3 was released in July 2022 at the following price points. If you’re in the US, the RRPs are as follows. The Full is $2195, the US Queen is $2295, and US King and California King sizes are $2495. This is significantly cheaper than the Pod 3 Max Mattress which starts at $3995 for the Full size. In the UK, only the Pod 3 Cover is available. The RRP is £2245 for a UK Double, £2345 for a UK King, and £2545 for a UK Super King. There are regular sales on the Eight Sleep website for big reduction days like Black Friday so do keep an eye out for updates as there have been reductions of up to $200/£100 recently.    

For this review, we slept on a UK King size with the Pod 3 Cover over an Emma Premium Mattress which fit perfectly. 

Eight Sleep Pod 3 Cover

(Image credit: Future)

Eight Sleep Pod 3 Cover review: Design

  • Minimalist black cover you won’t notice once its on
  • Installation is nightmarish for one person
  • Base unit requires space next to the bed  

Given that the Pod 3 has been specifically designed to bring Eight Sleep’s proprietary technology to as many mattresses as possible, the cover takes a little bit more work to install than your typical mattress cover. In the box are actually two different covers. One is a base layer with a zip, and then there’s the layer with the water-cooling technology which goes over the top and then zips into place. Straps then clip under the mattress itself to keep everything in position while you sleep. 

This top layer has an impressive set of water pipes that looks a lot like you’ll be plugged into the Matrix while you sleep. These hoses combine into one thick pipe which has to be fed down between your mattress slats and out from under your bed to click satisfyingly into the base unit. The black base unit itself, while looking innocuous enough, is 37cm high, 38cm long, and 18cm wide so won’t fit under your bed. This means you might have to get imaginative with storage solutions if you don’t want it to look like you’ve got a gaming PC in your bedroom. 

Eight Sleep Pod 3 Cover

(Image credit: Future)

While Eight Sleep patiently talks you through the entire process step by step on the app, the installation process is very tricky with one person. Our main reviewer managed to install it solo on a King size bed but not without losing a nail or two. The layers were exceptionally tight and getting the straps underneath was frankly nightmarish. We’re fit but you’re going to need someone else to help if you don’t want to cry mid installation. 

Thankfully once everything is installed and water poured into the base unit, the rest is plain sailing. The unit takes a few hours to get everything ready with a process called Priming and you can just leave it to set itself up. The zip and strap design keeps the cover securely installed and it hasn’t shifted over our entire review period.

Eight Sleep Pod 3 Cover

(Image credit: Future)

Eight Sleep Pod 3 Cover review: Features

  • Connected app is intuitive
  • Autopilot function is essential but only comes with subscription
  • Smart sensors provides ultra-detailed feedback 

The Eight Sleep app, which is available on both iPhone and Android is brilliantly intuitive. Which is very good news because you’re going to be using it a lot. It’s here where you’ll set your bedtime, temperature on the fly with the easy to use dial, and catch up on the ultra-detailed sensory tracking. You can even set any holidays with a handy Away mode so that you don’t need to tell your bed you aren’t there every day. 

Each night has a Sleep Fitness Score percentage. This is an aggregate of your time to fall asleep, how long you were asleep for, your wake consistency, and how long it actually took you to get up. Yes, you are going to be judged for how long you lurk in bed after the built in vibration function has gently roused you into consciousness. 

Eight Sleep Pod 3 Cover

(Image credit: Future)

A handy graph on the app each day also uses your heart rate and movement to let you know how much time you spent in REM sleep, light sleep and deep sleep, a good balance of which is required for a healthy night’s rest. But while it’s great to be able to see this data - and hopefully consider not eating before bed or consider drinking less caffeine later in the evening - the main draw of the entire affair is a mattress topper that reads your biometrics and actually keeps you asleep. 

And the only way it can match your fluctuating temperature is to change the temperature of the water. As we said above, this Autopilot function is essential if you want to clamber into a warm or cool bed and actually stay asleep while it alters to suit your peak sleeping environment. It’s also behind a paywall, which perhaps isn’t any different to buying a Peloton and then paying for a membership, but feels particularly expensive after such a heavy investment in the cover itself.

Eight Sleep Pod 3 Cover review: Performance

  • Preheating function is incredible
  • Autopilot comes with first-week teething issues
  • Our sleep was significantly improved 

But does the Pod 3 actually work? In short, yes. Exceptionally well. After we signed up for 8+ Pro, the first week was an uncomfortable and sweaty series of learnings for both the cover and us but after the Autopilot functionality kicked in properly there was a notable difference. Getting into a preheated bed on a freezing cold night just feels incredible, and knowing that you can turn it down slightly as you settle down, and then trust that the cover will do the same as you sleep feels brilliant.

We were sleeping under a thick winter duvet which we initially wondered would make everything far too warm but after its learning period, the Pod 3 cover adapted accordingly, and we were able to have full uninterrupted nights of sleep. When you look at the app the next day, you can see how many times the pod actively adjusted your temperature and by how much. You can also rate these changes if you had a particularly good night’s kip which will affect future nights. We found that after the initial learning period, there has been a real improvement. The only problem is when you go somewhere else and realise that you are sleeping far better in a carefully temperature controlled bubble. Yes, it’s a first world problem.

Eight Sleep Pod 3 Cover

(Image credit: Future)

The base unit itself isn’t noisy per se but you can hear it humming away like a very low fan, especially when it’s just turning on for the first time or changing the temperature for you. Anyone who requires complete silence to sleep might find it too much but we quickly became used to it and it’s never noisy enough to wake you up when it adjusts temperature, which would defeat things entirely. Think the levels of a gently hot radiator and you’ll be on the right track. 

There's a real range of temperatures here too. Heat of over 40C is available but we never found ourselves at over +4 - strangely it doesn't say how much it is in C - on the temperature dial which goes all the way up to 10. And there's a real noticeable difference between each setting. Even dropping to -1 on the dial  delivers an immediate cooling effect that will be especially welcome come hotter temperatures. 

Eight Sleep Pod 3 Cover review: Comfort

  • Mattress stays comfortable
  • You’ll notice room temperature changes on other side 

The next piece of good news is that you won’t physically feel  the Pod 3 Cover as you sleep. There’s an awareness of the water layer but unlike some electric blankets, there are no elements to feel so your mattress stays just as comfortable. What is worth noting though is the temperature of the bed when you don’t have the Pod 3 Cover on. Due to the fact that it’s water-cooled, water responds to room temperature. This means that climbing into bed on a cold night, means that your bed feels significantly colder than it already would have. If you and your partner have both sides on, you won’t notice but if you’re sleeping in winter with just one side powered, you’re not going to want to roll over to the other side. It’s a small point to make but an important note if you prefer to starfish all night and don’t want two different temperatures.  

Eight Sleep Pod 3 Cover

(Image credit: Future)

Should you buy the Eight Sleep Pod 3 Cover?

There’s no denying that this is an exceptionally expensive piece of sleep tech and the essential monthly subscription does seem steep. With Autopilot though the Pod 3 Cover creates what can often be an incredible sleep experience. The range of hot and cold temperatures means you’ll always be able to find just the right one to nod off,  and the suite of sleep insights in the app is impressive. The app itself is also exceptionally intuitive and we had no problems connecting to the hub at any point. The Pod 3 is a serious investment though so it’s a relief that you can trial it for 30 days to find out if it’s right for you.   

Louise Blain

Louise Blain is a writer and presenter specialising in tech, games, and horror entertainment. Thanks to the latter, she needs to avoid nightmares and regularly reviews the latest sleep tech for BBC Scotland, TechRadar and T3. Her specialist subjects include mattresses, weighted blankets, and sleep aids.