Flat sheet vs fitted sheet: pros, cons and differences

A flat sheet, also known as a top sheet, is a large, rectangular bed sheet. A flat sheet, sometimes referred to as a top sheet, is a non-fitted, rectangular piece of fabric that forms an essential part of a bedding set. Unlike a fitted sheet that has elastic corners designed to fit snugly around a mattress, a flat sheet is simply a large, rectangular piece of fabric that is hemmed on all sides to prevent fraying.

A fitted sheet is a specific style of bed sheet intended for use as a bottom sheet. Fitted sheets are designed and shaped with elasticised corners to match and fit the standard dimensions of a mattress and ensure they cover, fit and protect a mattress.

Now that we’ve defined each bed sheet, we can take a closer look at the common use cases of both sheets, staring with flat sheets:

They act as a layer between yourself and your duvet

A flat sheet can lie between yourself and your duvet; when used like this, the flat sheet shields you from direct contact with your duvet. This can be handy for maintaining a hygienic sleeping setup. The flat sheet can catch sweat, body oils and skin particles, and since flat sheets are easier to wash than duvets, using one can help keep your bed cleaner. 

Depending on its fabric, a flat sheet can also add an extra layer of softness to your bed and add an element of temperature control. If you get too hot during the night, you can push the duvet aside and sleep under the flat sheet alone, while when the weather is cooler, a flat sheet can be used as an extra layer of warmth. 

They can be used as a bottom sheet

A flat sheet can also be used as the bottom sheet on your bed, acting as a layer between yourself and your mattress or mattress protector. This layer protects your mattress from body oils, sweat, dirt and spills that could otherwise stain or damage your mattress. 

In addition, flat sheets are a pretty versatile option to use as a bottom sheet. Their rectangular shape makes them adaptable for various mattress sizes. For example, although flat sheets come in standard sizes, they don’t have elasticised corners like fitted sheets do, so they can be adapted to fit non-standard mattress sizes or shapes.

Fitted sheets are used solely as a bottom sheet

Compared to flat sheets with multiple uses, fitted sheets have a singular purpose: to act as the bottom sheet between yourself and your mattress. With elastic corners snugly fitting around a mattress, fitted sheets provide a secure, taut fit and stay in place even if you move around in your sleep. 

Apart from their designated functions, flat sheets and fitted sheets each possesses distinct pros and cons that it's important to be aware of:

Pros of flat sheets

Versatility

Flat sheets have multiple use cases, acting as a functional bottom sheet, a protective layer and a lightweight cover choice. 

Easy maintenance

Flat sheets are typically easier to wash, dry, and iron than fitted sheets or duvets. They are also easier to fold and store.

Hygienic

Flat sheets offer a layer of protection, keeping the heavier, more difficult-to-wash beddings (like blankets, duvets, or mattresses) clean from sweat, oils, and skin particles.

Aesthetic

A flat sheet can contribute to a neatly made bed, especially when used as a top sheet with the edges folded over the duvet.

Cons of flat sheets

Shifting

A flat sheet may shift or bunch up during the night, especially if used as a bottom sheet or if the sleeper moves a lot, which can lead to an uncomfortable surface.

Extra effort required

When used as a bottom sheet, flat sheets require more effort to secure properly compared to fitted sheets. You have to tuck in the edges under the mattress, often needing to make "hospital corners" to keep it in place.

Not a snug fit

Unlike fitted sheets, flat sheets don't have elastic edges to provide a snug fit when used as a bottom sheet.

Extra layer

For some, using a flat sheet as a top sheet adds an unnecessary layer, making the bed feel too warm, or the bedding feel too heavy.

Related article: 9 different types of beds sheets and their pros and cons

Pros of fitted sheets

Secure fit 

Fitted sheets have elasticized corners that ensure a snug fit on the mattress, keeping the sheet from moving around during sleep. This provides a taut and smooth sleeping surface.

Ease of use:

Fitted sheets are easier to put on a mattress than flat sheets used as bottom sheets. There's no need to tuck in edges or make "hospital corners".

Protects the mattress

Fitted sheets cover a mattress's entire top and sides, protecting it from sweat, body oils, and stains.

Neat appearance: When put on properly, fitted sheets give a bed a tidy and neat look due to their tight fit.

Cons of fitted sheets

Specific sizing

Fitted sheets need to match the mattress size exactly, or they won't fit properly. This can be challenging with non-standard mattress sizes or thicknesses.

Difficult to fold

Fitted sheets are notoriously difficult to fold neatly due to their elastic corners. 

Wear and tear

The elastic in fitted sheets can wear out over time, causing the sheet to fit less snugly. Similarly, fitted sheets may shrink with repeated washing, making them too small for the mattress.

Difficult to repurpose

Unlike flat sheets, fitted sheets can't be used as top sheets or easily repurposed for other uses due to their elastic corners.

Although flat and fitted sheets have differences in their use cases, they’re very often used together. Set up wise, the usual practice is to start by placing the fitted sheet on the mattress as the bottom sheet, ensuring a snug fit by tucking its corners securely. Next, you can add the flat sheet on top of the fitted sheet. The flat sheet usually serves as an extra layer for added comfort or as a cover. Many people like to drape the flat sheet over a duvet and tuck it in for a neat and inviting look. 

Hopefully, this guide has helped you understand exactly what flat and fitted sheets are, the differences between them and how they’re usually used. As you can see, flat and fitted sheets have some cross-over in what they can be used for. 

Flat sheets are a great choice if you like extra insulation and a layer between your bottom sheet and your duvet. Flat sheets are also good to use as a bottom sheet if you prefer a more flexible sheet that can be used for different-sized mattresses. For example, if you buy a flat sheet for a king-size bed, you know that it can be used as a bottom sheet for a queen or double bed. It will just require more tucking in. 

On the other hand, if you specifically need a well-fitted bottom sheet that provides a more defined fit to your mattress, a fitted sheet should be your priority. It is designed to fit securely around the mattress, giving a neat and tailored appearance. 

As we’ve covered, using both flat and fitted sheets together is also pretty common, so don’t feel that you can only use one or the other. At the end of the day it all comes down to the bedding combination that best suits your needs and what you find most comfortable.

Related article: A guide to bed sheets: thread counts, sizes and more