How to Measure for a New Mattress

Buying a new mattress is a significant investment in your comfort and sleep quality, so the last thing you want is to arrive at delivery day only to find that your perfect new mattress doesn’t fit on the bed!

A mattress usually can’t be returned once opened, so buying the wrong size can be a costly mistake. That’s why we’ve put together this guide to ensure you get all the measurements you need to find the perfect mattress and experience stress-free delivery.

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Key Takeaways
Before Measuring	Remove all pillows, blankets and bedsheets to ensure accuracy. Always use a tape measure and keep measurements consistent in either cm or inches throughout.
Mattress Length	Measure from head to foot along the top edge. For rounded edges, measure between the furthest points.
Mattress Width	Measure side to side across the widest part. Shaped mattresses may be thinner in places and require additional measurements for corner cuts or splits.
Mattress Depth	Measure from bottom to top, including any pillow tops or quilting. If going deeper than your current mattress, check that sheets, protectors and toppers will still fit.
Bed Frame	Measure the internal dimensions: length, width and depth. Check for protruding edges or structural features that may limit usable space.
Room Measurements	Check the widest dimension against doorways, hallways, staircases and banister heights. Allow at least 100mm of clearance between the mattress and any walls.
Tight Spaces	Consider roll-up mattresses or zip & link if access is restricted. Zip & link also allows each half to be set to a different tension.
Room Space	Leave at least 60–90cm of walking room around each side of the bed. TV beds need extra length and overhead clearance. Ottoman and storage beds require extra space for access.
Non-Standard Sizes	Most UK mattresses follow standard sizing, but antique or unusual bed frames may need a made-to-measure mattress.
Professional Help	If you’re unsure about measuring, call 01642 613684 for a measuring template (£15, refunded against purchase). . Double-check every measurement before ordering.

Measuring an Existing Mattress

If you’re replacing a mattress that you already own, you can just measure it directly.

Before measuring, make sure you remove anything covering the mattress, including pillows, blankets and bedsheets, so that your measurements will be accurate.

Always measure in centimetres or inches, ideally using a tape measure, and keep that consistent for each measurement.

An image of someone measuring a divan base with a tape measure

Measure:

Length: From head to foot, along the top edge of the mattress. If your mattress has rounded edges, just measure the furthest points.

Width: Side to side, across the widest part. While this will be consistent for most mattresses, shaped mattresses may be thinner in some places.

Depth: From the bottom to the top of the mattress, including any pillow tops or quilting. If you want your new mattress to be deeper than the current one, make sure that your bedsheets and any protectors and toppers will still fit over it.

If you have an odd-shaped mattress, such as for a caravan or narrowboat, you will need to make extra measurements for corner cuts, splits in the mattress, etc.

If you’re worried about making these measurements yourself, call our team on 01642 613684 and we can send you a template to use. These are £15, but the cost will be deducted from your mattress if you choose to buy with us.

Remember to double-check each measurement to make sure that it is correct.

Most UK mattresses will conform to standard sizing, with some slight variation depending on years of use or manufacturing differences. If you do find your mattress isn’t a standard size or shape e.g. if you have an antique bed frame, then we offer a fantastic range of special size mattresses, which can be made to measure.

Measuring a Bed Frame

If you're buying a mattress to fit a bed frame, just measure the internal dimensions of the frame where the mattress sits.

Someone measuring a bed frame with a tape measure

Measure:

Internal Length: Inside the headboard to the inside of the footboard.

Internal Width: From one inner side rail to the other.

Maximum Depth: How deep the frame allows a mattress to sit. When choosing what depth mattress you want, you should also measure this against the headboard and footboard, to see how much will be covered by the mattress.

Check for any protruding edges, footboards, or structural features that may limit usable space.

Measuring the Room

Of course, having a mattress that fits your bed isn’t much use if you can’t get it through the door!

When buying a new mattress, it’s also important to look at how it will fit in your home. Take the widest dimension of your mattress or bed frame and check that against the width and height of any doorways, hallways and staircases to see if it can fit through. You should also measure the height of your landing banister to see if the mattress could be lifted over the top of it.

Ideally, there should be at least 100mm of space between the mattress and any walls to prevent it from bumping against anything, which may cause marks or scratches.

If your space is limited and you think we might struggle to get a mattress in, don’t worry! We offer a variety of space-saving solutions.

Roll-Up Mattresses

Roll-up mattresses are full-size mattresses that have been compressed and vacuum-sealed into a bag or box, allowing them to be easily transported and carried through tight spaces. Once in your bedroom, the mattress can be rolled out and left to expand back to its original size over a few hours.

Zip & Link Mattresses

Zip & link mattresses are also a great option for larger sizes. These come as two separate halves, which are then zipped together. Not only does this make them much easier to move than a full king or super king, but the two halves can also be set to different tensions, so they’re ideal if your partner prefers a different mattress firmness than you.

To learn more about roll-up or zip & link mattresses, check out one of our extensive blogs, which will answer any questions you might have:

Measuring for a New Bed

If you are planning to buy both a new bed and mattress, then you will also want to measure the space around your current bed (or the area where you plan to put the new bed).

For most beds you will want to leave at least 60 – 90cm walking room around each side, but some types will require more room.

TV Beds

TV beds are longer than standard beds, to accommodate the TV stored in the footboard. You will also want to check the space above the footboard to make sure the TV won’t smack into anything when it rises!

Ottoman Beds

Ottoman beds lift up, either at the end or one side. You will need to leave extra room around whichever side opens so that you can easily lift the bed and move items in and out of the ottoman.

Similarly, storage beds will need extra room. When researching the bed, find out where the drawers are located and how far they pull out, then measure the space to make sure they can be fully pulled out. Again, you will want to leave extra space so that you can easily access the drawers.

Conclusion

Getting your mattress measurements right is the key to ensuring a smooth and stress-free delivery. By taking the time to measure your existing mattress or bed frame and room accurately, you’ll avoid the frustration of an ill-fitting mattress and enjoy a perfect night’s sleep sooner. Whether you’re choosing a standard size, a made-to-measure option, or one of our convenient roll-up or zip and link mattresses, you can rest easy knowing you’ve found the right fit for your home and your comfort.