The Emma Premium Topper includes innovative Premium ThermoSync technology for a cooler sleep.
The Emma Premium Topper is a luxury choice with excellent temperature regulation. 🌡️
It's made from a ThermoSync foam layer and adaptable HRX comfort foam.
This duo offers a combination of support and breathability. 🛠️
The Emma Premium mattress topper is 9 cm (3.5 inches) deep, making it an ideal choice for those looking for a thick mattress topper.
The advanced foam layers provide effective pressure relief and align your spine for restful sleep.
The cover is fully removable and machine-washable, which keeps the topper fresh and improves longevity. 🧼
All materials of the Emma Premium Topper comply with the OEKO-TEX® Standard 100.
Emma Sleep offers a 100-night trial and a 10-year guarantee, so you can purchase worry-free with extra peace of mind. 😌
The Emma topper includes free delivery & returns in 2 - 7 working days.
55% OFF EMMA PREMIUM TOPPER + 5% OFF W/ "SLEEPHEROUK5"
Emma Premium Topper | |
Materials: | ThermoSync foam, HRX comfort foam, polyester cover |
Depth: | 9 cm (3.5 inches) |
Trial period: | 100 nights |
Guarantee: | 10 years |
Available sizes: | Single, small double, double, king, super king |
The Hypnia mattress topper is made from deep, pressure-relieving memory foam.
The Hypnia Ultimate mattress topper is a noteworthy upgrade to improve the comfort of your mattress.
It is 8 cm (3.14") deep, providing a deep layer of comfort to your current mattress.
The Hypnia Ultimate includes memory foam technology that perfectly follows your body shape and aids in blood circulation. 💓
Designed to relieve pressure, it works wonders in aligning the body and reducing tension in the lumbar region or neck.
The Hypnia topper has a soft and absorbing feel, gently hugging around the body like you're sinking into a marshmallow.
The topper includes a removable and washable cover, keeping your sleep environment fresh and hygienic. ✨
It's also OEKO-Tex certified, meaning it's been tested for harmful substances.
The Hypnia topper has a non-slip base designed to keep it secure on the mattress throughout the night.
However, the extra-deep topper sometimes slid off the bed during testing, so we would favour a design with straps for increased stability.
Its ultra-breathable cover promotes ventilation, reducing the likelihood of nighttime sweating. 💨
The Hypnia Ultimate mattress topper comes with free delivery in 2 to 3 working days.
25% OFF HYPNIA TOPPER + 2 FREE PILLOWS W/ PILLOWS2
Hypnia Ultimate Mattress Topper | |
Materials: | Memory foam, 100% polyester cover |
Depth: | 8 cm (3.14") |
Trial Period: | 200 nights |
Guarantee: | / |
Available Sizes: | Single, small double, double, king, super king |
All foams used in this topper are CertiPUR-certified, ensuring they're free from toxins, heavy metals, dyes, and harmful chemicals.
The Simba Hybrid mattress topper is one of the most unique toppers on the market.
Proudly designed by the British Simba Sleep, the Simba topper features three layers:
- Simba-Pure synthetic latex (2.5 cm / 1 inch)
- 2,500 Aerocoil 20 mm mini pocket springs, enclosed in 100% polyester pockets
- High-resilience Simba-Pure base foam (2 cm / 0.7 inches)
The Simba-Pure foam is CertiPUR-certified and guaranteed to be free from TCPP, phosphates, parabens, biocides and persistent organic pollutants. 🌱
This is a cooling mattress topper as the springs allow for maximum airflow.
The cover with 3D mesh fabric is also ultra-breathable, further enhancing airflow.
This helps with temperature regulation, ensuring you stay cool and fresh all night long. ❄️
Because of its hybrid composition, the Simba topper also feels much firmer than pure foam toppers.
This is great if you just want to add a touch of firmness. 🧱
The Simba topper has an anti-slip base and elasticated straps to keep it firmly in place on your mattress.
The Simba mattress topper comes with free delivery & returns, a 14-day returns policy, and a 1-year guarantee.
Simba Hybrid Mattress Topper | |
Materials: | Synthetic latex, mini pocket springs, Simba-Pure foam |
Depth: | 7 cm (2.7 inches) |
Trial period: | 14-day returns policy (you can try out the topper in these 14 days but this is subject to change) |
Guarantee: | 1 year |
Available sizes: | Single, small double, double, king, super king |
This 10 cm (4") thick quilted topper adds extra comfort to your sleep.
The Acrali Home mattress topper stands out as the thickest mattress topper UK.
Made with super soft premium quality microfibre, the Acrali Home mattress topper moulds around the body.
Microfibre is made with airy fibres, making it a breathable choice for those that get too warm at night.
This 10 cm deep mattress topper has a baffle box stitched design to ensure all the filling stays in place.
The Acrali Home mattress topper is 100% machine washable and tumble-dry friendly.
The thick mattress topper comes with elasticated straps that grip onto the corner of the mattress to keep it in place.
The Acrali Home mattress topper includes free delivery and returns.
Acrali Home Mattress Topper | |
Materials: | Microfibre |
Depth: | 10 cm (4 inches) |
Trial period: | / |
Guarantee: | / |
Available sizes: | Standard single, small double, double, king, super king |
How we test products
Our mission is to take the guesswork out of finding the perfect sleep products.
We've dedicated hundreds of hours to testing mattresses and sleep accessories, and rely on a team of testers of differing weights, temperature preferences, and sleeping positions to evaluate each product.
Tested products are granted the Sleep Hero tested stamp of approval, a mark of our review's reliability.
If we haven't personally tested a product, please be assured that we invest significant time and energy into scouring the UK market and researching the best recommendations, and we work with a team of sleep experts who review our articles, ensuring that the insights we provide are not only relatable but also reliable.
How thick should a mattress topper be?
Mattress toppers are available in a range of thicknesses. 🙌
Most mattress toppers start around 4 cm - 5 cm (1.57 - 1.9") deep.
An extra thick mattress topper can measure 7 - 10 cm (3 - 4"), almost double the thickness of a regular topper.
What is the thickest mattress topper?
The thickest mattress topper is around 10 cm (4") in depth.

A 10 cm (4") thick mattress topper can provide even more comfort than a standard mattress topper.
The additional depth moulds around your hips and shoulders and relieves pressure from these areas.
An extra thick mattress topper can even make a firm mattress feel softer. 😍
The Acrali Home mattress topper, made with soft microfibre, is one of the thickest toppers available.
Take a look below:
What is a mattress topper?
A mattress topper sits on top of your mattress.
It is designed to improve the feeling of your mattress by adding an extra layer of comfort. ☁️

If your mattress lacks support or feels too firm, a mattress topper can help to enhance the overall feel. 💞
Extra deep mattress toppers come in various materials, including microfibre, wool, duck feather, and memory foam.
But what kind of thickness should you desire? 👇
Do you need a thick mattress topper?
So, what type of person requires a thick mattress topper?
Many people could benefit from a thick mattress topper, but it depends on your weight, sleeping position and firmness preference.
Thick mattress toppers are best for side sleepers
Deep mattress toppers are a perfect choice for side sleepers. ✔️

This is because side sleepers need a mattress that moulds around the hips and shoulders when sleeping in the side position.
The best extra thick mattress topper will contour to the body's shape and relieve pressure in the joints.
A thick memory foam mattress topper gently contours around the body's shape and provides a weightless feeling.
Thick mattress toppers are ideal for lighter people
Lighter-weight people may benefit from a thick mattress topper. 👌

Often, even medium-feel mattresses can feel too firm for lighter people. 🧱
A mattress that is too firm can put pressure on the hips and shoulders and have you waking up with aches and paints.
A deep mattress topper cushions those areas whilst encouraging better spinal support for those who weigh less.
Thick mattress toppers can help those with joint pain
Some people suffer from aches and pains in the hips, pelvic region, elbows, and shoulders.
A mattress that is too firm puts pressure on the joints and spine, which can have you tossing and turning throughout the night. 🙁

However, a thick mattress topper will cushion around these sensitive pressure points.
Those who are elderly, pregnant or suffer from chronic pain could benefit from an extra-thick mattress topper.
Alternatively, those struggling to sleep during pregnancy should consider a body pillow for extra support.
Who is a thick mattress topper not suitable for?
A thick mattress topper (or any mattress topper) isn’t suitable for everyone. 👎
Some may find that a mattress topper makes their bed feel too soft.
If you are on the heavier side, you may experience too much sinking when using a deep mattress topper.
Likewise, stomach sleepers need a firm mattress that lifts their back and helps to keep the spine straight. 📏

A thick mattress topper could create a bend in the spine in this position, resulting in back pain.
If you’re trying to make a soft mattress feel firmer, then a mattress topper isn’t the way to go.
Whilst firm mattress toppers are available, a thick mattress topper typically creates a softer feel.
Instead, consider purchasing a firmer mattress like the DreamCloud Luxury Hybrid or Panda Hybrid Bamboo mattress.
When is it time to buy a new mattress?
It’s important to remember no matter how thick the mattress topper is, there is only so much that it can do.
An extra thick mattress topper can help relieve pressure and provide additional comfort.
However, if your mattress is old and dipping, it might be time to throw in the towel. 🙅

A mattress topper isn’t going to be a cure for indents or mattresses that provide no support.
Instead, consider replacing the mattress altogether.
Buying a mattress doesn’t have to be stressful, and most now come with sleep trials and extended warranties to keep you protected. 🤞
Our best mattress guide has the top UK mattress recommendations.
Can you wash a thick mattress topper?
Some thick mattress toppers are machine-washable or include washable covers. 🧼

This is great for those with allergies who need to keep on top of removing bacteria and dust mites. 🦠
Simply pop your mattress topper into the washing machine with your laundry detergent on the recommended setting.
You should check the product label to see if the mattress topper you buy is washable or has a washable cover.
Can I wash a thick memory foam mattress topper?
Memory foam toppers are not washable. ❌

That’s because water can damage memory foam and void your warranty.
We recommend using a waterproof mattress protector over your mattress topper.
This will protect the material and prevent you from damaging the topper and losing your warranty. ☔
Our favourite waterproof mattress protectors:
Thick mattress topper sizes
A deep mattress topper comes in standard UK sizes.

This includes:
- Thick mattress topper single: 90 x 190 cm (3’ x 6’3”)
- Thick mattress topper small double: 120 x 190 cm (4' x 6'3")
- Thick double mattress topper: 135 x 190 cm (4’6” x 6’3”)
- King size mattress topper thick: 150 x 200 cm (5’ x 6’6”)
- Thick mattress topper super king size: 180 x 200 cm (6’ x 6’6”)
You should choose a mattress topper to match the size of your current mattress.
For example, you should purchase a thick mattress topper king-size option if you have a king-size mattress.
On the other hand, those with a double mattress should opt for an extra thick mattress topper double size.
Thick mattress topper depths
Mattress toppers also come in a range of depths. ✅
Extra deep mattress toppers are usually 7 - 10 cm (2.7 - 3.9 inches) deep.
Thick mattress topper prices
Thick mattress topper prices vary from budget-friendly to high-end. 💰

IKEA mattress toppers are budget-friendly, but their quality and durability may not always meet expectations. 😟
Cheaper mattress toppers also don’t tend to include sleep trials or warranties that can protect you from wasting your money.
Luxury mattress toppers such as the Tempur topper include the best materials but can cost as much as a brand-new mattress.
Consider mid-range mattress toppers such as the Simba mattress topper if you are looking for a good quality topper that doesn't break the bank.⚖️
We recommend investing in a decent quality product that is within your means.
Thick mattress topper discount codes
Is an ultra thick mattress topper out of your price range? 🤔

Luckily, thick mattress topper voucher codes can help you stick to your budget.
Just bookmark our discounts page for all the best deals.
You can also sign up for our newsletter for exclusive discount codes. 🏷️
Should you buy a thick mattress topper?
Whether or not you need a thick mattress topper depends on your needs and lifestyle.
A thick mattress topper is an excellent choice for side sleepers, those with joint pain, or lighter weight sleepers who will experience a good night’s sleep on a thick topper.
But they’re not for everyone.🤔
For many, a regular mattress topper or a brand new mattress might be more appropriate.