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The best mattress topper thickness for most people is between 2 inches (5cm) and 3 inches (7.6 cm). The choice of thickness depends on your body weight, your sleeping position, and how much you want to change the feel of your mattress.
The most common mattress topper thickness options range between 1 inch (2.5 cm) and 4 inches (10 cm), with each option suiting a particular set of needs.
The guide below is for anyone considering buying a new mattress topper and unsure of what size is best for them.
The mattress topper thickness you need depends on what you're buying it for, as outlined below.
The table below compares the four mattress topper thicknesses in terms of feel, pressure relief, sheet fit, cost, and who each one suits.
| 1 inch (2.5 cm) | 2 inches (5 cm) | 3 inches (7.6 cm) | 4 inches (10 cm) | |
|---|---|---|---|---|
| Change to mattress feel | Slight extra cushioning | Noticeably softer surface, support unchanged | Softer surface that shapes to your body | Feels like a different mattress |
| Pressure relief on hips and shoulders | Minimal | Moderate | Deep | Deepest |
| Sheet fit | Standard fitted sheets fit | Standard fitted sheets fit | Deep-pocket sheets may be needed | Deep-pocket sheets may be needed |
| Cost | Lowest | Low to mid | Mid to high | Highest |
| Best for | Slightly softening a mattress you otherwise like | Back and stomach sleepers who want a softer surface | Side sleepers and people with hip or shoulder pain | Heavier sleepers and anyone who wants a plush surface on a firm mattress |
A 1-inch mattress topper adds a little more cushioning than a mattress pad and much less than a 2-inch topper.
A 1-inch topper is too thin for your hips and shoulders to sink into, so it does not provide extra firmness or pressure relief.
A 2-inch mattress topper adds a more noticeable degree of comfort without significantly altering the firmness of the existing mattress.
2-inch mattress toppers suit most back and stomach sleepers, improve comfort, and preserve stability. Light to average-weight sleepers benefit from better pressure relief without losing the support of the underlying mattress.
A 2-inch topper doesn't offer enough cushioning for side sleepers who need deeper contouring, which is when the sleep surface adapts to your body shape. Heavier individuals usually find they need a thicker mattress topper to ease pressure points.
A 3-inch mattress topper suits sleepers who need to relieve pressure points without making the mattress too soft.
3-inch toppers let your body sink in a little further, which takes pressure off the shoulder and hip, while the mattress underneath still keeps your spine in line.
Adding a thicker mattress topper increases bed height, which can affect the fit of sheets without sufficient pocket depth, and for some people. A higher bed may be inaccessible for shorter or less mobile people. 3-inch toppers are also more expensive than 1- and 2-inch varieties.
A 4-inch mattress topper provides more comfort and support than any thinner topper. Thicker toppers are best for heavier sleepers and anyone who wants to alter their mattress firmness significantly.
A 4-inch thickness allows the body to sink deeper and helps distribute your body weight evenly, which may help relieve lower back pain and pressure on sensitive joints.
Which of the four thicknesses to choose depends on your body weight, your sleeping position, and the mattress you already own.
To choose the best thickness for your mattress topper, consider your body weight, sleeping position, topper material, existing mattress firmness and condition, bed height, and budget.
The higher your body weight, the thicker your mattress topper needs to be.
We recommend these thicknesses for each weight group.
Side sleepers need a thicker topper than people in any other sleeping position, because their weight is supported by one shoulder and hip.
We recommend the following for side, back, and stomach sleepers.
Latex, memory foam, and wool compress differently under your weight, so the same topper thickness feels different depending on the material.
Here is how the three common topper materials compare.
A thick topper makes a bigger difference to how firm your sleep surface is, and does more to extend the life of a worn mattress.
An old mattress that has lost its cushioning needs a thicker topper than a new one. After years of being compressed every night, the foam in the top layers of a mattress loses height and stops springing back. A 3-inch (7.6 cm) or 4-inch (10 cm) topper adds the cushioning those layers no longer give.
Adding a topper does not fix a mattress that severely sags in the middle, because the topper simply sinks into the dip. If you experience a severe sag, you need a new mattress.
Make sure you understand that mattress toppers make your bed taller. A higher bed surface is not always an issue, but it may have the following side effects.
Before buying a thick mattress topper, make sure that the additional height doesn't affect your ability to get in and out of bed, and that you have sheets that will accommodate the extra inches.
Thicker toppers cost more, but the material makes a bigger difference to the price than the thickness.
A thick synthetic memory foam topper costs less up front than a thin organic latex one. Good quality genuine organic latex toppers last roughly twice as long as polyurethane foam, so the eco-friendly option is better value in the long term.
A 2-inch (5 cm) mattress topper is enough for back and stomach sleepers who weigh 230 lbs (104 kg) or less and want a noticeably softer surface.
Two inches is not enough for side sleepers or heavier sleepers.
Get a 2-inch (5 cm) mattress topper if you sleep on your back or stomach and want a softer surface, but don't need extra support.
Get a 3-inch (7.6 cm) mattress topper if you sleep on your side or want to significantly change the firmness and feel of your mattress.
A 4-inch (10 cm) mattress topper is not too thick for heavier sleepers or for anyone who wants a firm mattress to feel plush.
Four inches is too thick for someone who likes their mattress and wants only a little more softness, because it changes the feel of the bed more than any thinner topper.
There is no mattress topper thickness proven to relieve back pain, so choose the thickness by your weight and sleeping position, as any other sleeper would.
Firmness and support do more for back pain than thickness, as our guide to the best organic mattresses for back pain explains. A topper that is too soft for your weight lets your hips sink, which bends your lower back and can make the pain worse.
No, a 6-inch (15 cm) mattress topper is thicker than we recommend for any body weight or sleeping position.
6-inch mattress toppers are the same depth (and price) as a thin mattress and are far more than most people need in a topper.
