Fitted Sheets: How to Choose the Right Size and Pocket Depth

Have you ever woken up to find that one corner of your fitted sheet has slipped off the mattress? Or struggled to stretch a sheet over your bed, even though it’s supposed to be the right size?

It’s a small detail that can quickly become frustrating. And quite often, the problem isn’t the sheet itself, but its dimensions or pocket depth.

Because choosing a fitted sheet that fits perfectly isn’t just about knowing the width and length of your mattress. Its thickness matters just as much!

So, what size fitted sheet should you choose for a 140 × 200 or 160 × 200 cm bed? What exactly does a 30 cm pocket depth mean? And how can you stop your fitted sheet from slipping off during the night?

Here’s our practical guide to finding the perfect fit and enjoying a comfortable, neatly made bed every night.

Why Is Choosing the Right Fitted Sheet Important?

We often spend plenty of time choosing the right mattress, duvet or pillow. Yet the fitted sheet also plays an essential role in how comfortable our bed feels.

After all, it’s the fabric we sleep directly on, night after night. It should therefore feel pleasant against the skin while staying securely in place, even when we move around in our sleep.

A poorly fitting fitted sheet can cause several problems:

• Corners that come loose during the night.
• Uncomfortable wrinkles forming underneath your body.
• Fabric that feels too tight and is difficult to put on or remove.
• Elastic edges that don’t fit properly underneath the mattress.
• Premature wear and tear on the fabric or seams.

The good news? A few simple measurements are usually all you need to avoid these problems.

What Size Fitted Sheet Do You Need for Your Mattress?

Let’s start with the basics: width and length.

Your fitted sheet should match the actual dimensions of your mattress, not those of your bed frame or base.

For example, if your mattress measures 160 cm wide and 200 cm long, you should choose a 160 × 200 cm fitted sheet.

It might sound obvious, but with so many mattress sizes available, it’s surprisingly easy to get confused.

Common Fitted Sheet Sizes

Here’s a helpful table showing some of the most common European mattress sizes and their corresponding fitted sheets:

Please note that standard bed sizes vary between countries. For example, UK king-size and super king-size mattresses have different dimensions from some European equivalents. Always check the actual measurements rather than relying on the bed’s name.

At Zizzz, our organic cotton fitted sheet collection includes sizes such as 90 × 200, 140 × 200, 160 × 200 and 180 × 200 cm, depending on the model.

These sizes are suitable for many modern single and double beds.

What Is the Pocket Depth of a Fitted Sheet?

Pocket depth is probably one of the least understood measurements when buying bed linen. Yet it’s essential for achieving a proper fit.

It refers to the depth of the fitted sheet’s corners, which extend down the sides of the mattress.

The elasticated edge helps keep the fabric securely tucked underneath.

The thicker your mattress, the deeper the pockets you’ll generally need.

What’s the Difference Between Pocket Depth and Mattress Thickness?

This is where things get a little confusing!

Pocket depth refers to the depth of the fabric at the corners of a fitted sheet.

Mattress thickness, on the other hand, refers to the actual height of your mattress, measured from its bottom to its upper surface.

For a fitted sheet to stay securely in place, its pockets generally need to be slightly deeper than the mattress itself. This extra fabric allows the elasticated edge to tuck underneath the corners.

As a general rule, it’s useful to allow approximately 5 to 7 cm of extra depth.

For example, if your mattress is 25 cm thick, you would usually look for a fitted sheet with a pocket depth of around 30 to 32 cm.

However, there’s an important detail to remember: some brands advertise the actual pocket depth, while others indicate the maximum mattress thickness their fitted sheets can accommodate.

These two measurements aren’t interchangeable.

How to Measure Your Mattress for the Right Fitted Sheet

You don’t need to be a bedding expert! All it takes is a measuring tape and a few minutes.

Step 1: Measure the Width

Measure your mattress from one side to the other, without including the bed frame.

You might find that it measures 90, 140, 160 or 180 cm, for example.

Step 2: Measure the Length

Next, measure your mattress from the head to the foot.

Pay particular attention to whether it’s 190 or 200 cm long. That 10 cm difference might not sound like much, but it makes a real difference when it comes to a properly fitting sheet.

Step 3: Measure the Thickness

Measure the height of your mattress from its base to its highest point.

If your mattress has a quilted or padded surface, make sure to include that additional thickness.

And if you use a mattress topper underneath your fitted sheet, remember to include its height too.

For example:

You’ll therefore need a fitted sheet suitable for a mattress at least 27 cm thick, even though the mattress itself is only 22 cm high.

This is a particularly common mistake among people who use a mattress topper to make their bed feel softer and more comfortable.

What Pocket Depth Should You Choose for a Thick Mattress?

Modern mattresses can be surprisingly thick, particularly pocket-sprung, hybrid and multi-layer comfort models.

A standard fitted sheet isn’t always deep enough to accommodate them.

Here are some general guidelines to help you choose the right pocket depth:

These measurements are approximate and assume that pocket depth is measured from the top of the sheet to its elasticated edge. The actual fit also depends on the fitted sheet’s design and the manufacturer’s recommendations.

At Zizzz, we prefer to indicate the maximum mattress thickness our fitted sheets can accommodate, making it easier for you to choose the right model.

Zizzz Fitted Sheets: Up to 30 cm for Percale and 26 cm for Satin

Our two organic cotton fitted sheet collections have slightly different fitting dimensions.

Our organic cotton percale fitted sheets are therefore suitable for mattresses up to 30 cm thick.

Our organic cotton satin fitted sheets, meanwhile, are designed for mattresses up to 26 cm thick.

Here’s a practical example: if you have a mattress that’s 28 cm thick, our percale fitted sheet is suitable, while our satin model isn’t designed for that height.

That’s why it’s always worth checking this detail before choosing your bed linen.

Percale or Cotton Satin: Which Fabric Should You Choose for Your Fitted Sheet?

Once you’ve found the right dimensions, it’s time to think about comfort!

After all, a good fitted sheet shouldn’t just stay securely on your mattress. It should also feel comfortable against your skin, allow air to circulate and suit your personal sleeping preferences.

At Zizzz, we’ve chosen to work with organic cotton, offering two different weaves with distinct textures: percale and satin.

Organic Cotton Percale: Freshness and Lightness

Do you love that wonderful feeling of slipping into a freshly made bed with cool, crisp sheets?

Percale might just become your favourite fabric.

Percale isn’t a different fibre from cotton. It’s a particular type of weave.

Its closely woven structure creates a slightly matte finish, a cool touch and a crisp yet lightweight feel.

Our Zizzz percale fitted sheets are made from GOTS-certified organic cotton, with a thread count of 220 and a fabric weight of 132 g/m².

They’re also made in Portugal, reflecting our commitment to European manufacturing.

Percale is particularly appealing if you:

• Love the feeling of cool, fresh sheets.
• Tend to get too warm during the night.
• Prefer a natural, slightly matte texture.
• Want durable bed linen for everyday use.

Discover our organic cotton percale fitted sheets, available in several colours and sizes.

Organic Cotton Satin: Softness and a Silky Feel

If you prefer slipping into wonderfully soft, smooth and comfortable sheets, cotton satin might be a better choice for you.

Contrary to what some people think, satin isn’t necessarily a synthetic material.

Just like percale, satin refers to a type of weave. At Zizzz, our satin is made from organic cotton.

Its particular weaving technique creates a smoother surface that reflects light slightly, giving the fabric its characteristic silky feel and subtle sheen.

Our satin fitted sheets have a thread count of 276 and a fabric weight of 120 g/m².

They come in a beautiful natural ecru shade, without any added dyes.

Cotton satin is particularly appealing if you:

• Love a soft, silky feel.
• Prefer a smooth surface against your skin.
• Appreciate fabrics with a subtle natural sheen.
• Enjoy timeless, natural colours.

Discover our organic cotton satin fitted sheets.

Choosing between percale and satin is ultimately a matter of personal preference. Both are made from natural, breathable fibres, but they offer different sensations.

Why Choose an Organic Cotton Fitted Sheet?

We spend a significant part of our lives in bed. And among all the different elements of our bedding, the fitted sheet is one of the fabrics that stays in direct contact with our skin for the longest time.

It therefore makes sense to pay attention to what it’s made from.

Organic cotton is a natural plant-based fibre that’s breathable, pleasant against the skin and well suited to everyday use.

Unlike conventional cotton farming, organic cotton cultivation prohibits genetically modified seeds and certain synthetic pesticides and fertilisers.

At Zizzz, our percale collection is GOTS-certified. This certification sets environmental and social requirements throughout the textile supply chain.

Our satin is also made from certified organic cotton, although the finished product itself does not carry GOTS certification.

This transparency is part of our philosophy: offering high-quality natural materials without making unnecessary promises.

Because sleeping well also starts with feeling comfortable in your own bed.

Why Does My Fitted Sheet Keep Coming Off the Mattress?

You’ve chosen the correct width and length, but your fitted sheet still slips off during the night?

There are several possible explanations.

The Pockets Aren’t Deep Enough

This is one of the most common reasons.

If the pocket depth is too shallow for your mattress, the elasticated edge can’t tuck far enough underneath it.

As a result, the corners may pop off as soon as you move around in your sleep.

The Fitted Sheet Is Too Large

A fitted sheet that’s too big can also cause problems.

When the fabric isn’t sufficiently fitted, wrinkles can appear and the sheet may shift around during the night.

You’re Using a Mattress Topper

If your fitted sheet stayed perfectly in place before you added a mattress topper, the combined height may now be too much for it.

In this case, choose a fitted sheet with enough depth to cover both the mattress and the topper.

The Elastic Has Lost Its Stretch

Over time and after repeated washing, the elastic in a fitted sheet can lose some of its elasticity.

Even if the dimensions are correct, loose elastic can prevent the sheet from staying securely in place.

Remember to follow the washing and care instructions on the label to help preserve the fabric and its finishing details for as long as possible. Our guide on how to care for your organic bed linen gives you all our tips.

Common Mistakes to Avoid When Buying a Fitted Sheet

To make your life easier, here’s a quick summary of the most common mistakes:

Taking just a few minutes to check these details can save you plenty of frustration when making your bed.

Frequently Asked Questions About Fitted Sheet Sizes and Pocket Depth

What pocket depth do I need for a 25 cm mattress?

For a mattress that’s 25 cm thick, a pocket depth of around 30 to 32 cm is generally a good starting point. Alternatively, choose a fitted sheet whose manufacturer specifically states that it’s suitable for mattresses up to 25 cm thick.

What’s the difference between a 30 cm pocket depth and a sheet for a 30 cm mattress?

A 30 cm pocket depth normally refers to the depth of the fabric at the corners. It often fits a slightly thinner mattress because some extra material is needed to tuck underneath. A fitted sheet advertised as suitable for mattresses up to 30 cm thick, on the other hand, is specifically designed to accommodate that maximum height.

What fitted sheet size do I need for a 160 × 200 cm mattress?

Choose a 160 × 200 cm fitted sheet, then check that its pocket depth is suitable for your mattress thickness. This European queen-size format is available in the Zizzz collection.

What fitted sheet should I choose for a 30 cm thick mattress?

You’ll need a fitted sheet specifically designed for mattresses up to 30 cm thick. At Zizzz, our organic cotton percale fitted sheets are suitable for mattresses up to this height.

Can I use a 140 × 200 cm fitted sheet on a 140 × 190 cm mattress?

It’s generally not recommended. The extra 10 cm of fabric may create wrinkles and prevent the sheet from fitting securely. It’s better to choose a fitted sheet that matches the exact dimensions of your mattress.

Should I measure my mattress with the topper included?

Yes, if your fitted sheet needs to cover both. Measure their combined thickness to ensure you choose a sheet with sufficient depth.

Which fitted sheet is best if I get too hot at night?

If you’re looking for a cooler sleeping experience, organic cotton percale is an excellent option. Its naturally cool feel and breathable structure make it particularly pleasant for people who tend to get warm during the night.

The Right Fitted Sheet for More Comfortable Nights

Choosing the right fitted sheet isn’t complicated once you know the three essential dimensions of your mattress: width, length and thickness.

By taking a few moments to check these measurements and the required pocket depth, you can enjoy a sheet that stays neatly in place, without uncomfortable wrinkles or corners coming loose in the middle of the night.

And once you’ve found the right size, all that’s left is to choose the fabric you love sleeping in.

At Zizzz, we believe small details can make a big difference when it comes to sleep. That’s why we favour natural materials such as organic cotton, with carefully chosen weaves designed to offer softness, breathability and comfort.

Cool, crisp percale or soft, silky satin: the choice is yours.

Because a beautifully made bed, with perfectly fitting sheets that feel wonderful against your skin, is already a lovely invitation to a good night’s sleep.

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Our Mission at Zizzz

Enhancing quality of life and well-being through better sleep

At Zizzz, our mission is to improve quality of life by promoting good sleep as an essential component of overall well-being.

We offer products and resources that promote restorative and revitalizing sleep, recognizing it as one of the three pillars of a healthy lifestyle, alongside a balanced diet and regular physical activity.

By prioritizing quality sleep, we empower individuals to lead healthier and happier lives.

Preserving our environment and helping to build a better future

We achieve this goal by using only natural materials such as wool, traceable down, and organic cotton in our products, ensuring a luxurious and eco-friendly sleep environment.

Committed to sustainability and ethical practices, we produce locally, supporting local economies and reducing our carbon footprint.

Choosing Zizzz means investing in your own well-being while contributing to a more sustainable future for all.