---
title: "How to Choose a Mattress (UK Decision Guide)"
description: "How to choose a mattress in the UK: pick the type, match spring tension to your weight, then feel, size, base, trial and warranty. No brand rankings."
url: "https://bedguide.co.uk/mattresses/how-to-choose-a-mattress/"
category: "mattresses"
primary_entity: "how to choose a mattress"
date_published: 2026-08-03
date_modified: 2026-09-25
---

# How to Choose a Mattress (UK Decision Guide)

> To choose a mattress, pick the build type first. Then match spring tension or foam support to your body weight. Then choose the top feel for how you sleep. Check the UK size in centimetres and your bed base. Last, read the trial, returns and warranty terms before you pay.

## Key facts

- Materials: pocket springs, open coil springs, memory foam, latex, hybrid stacks

Key facts:

- Build: Type first — Pocket, hybrid, foam, latex or open coil — then tension.
- Spring tension rule of thumb (NBF): Heavier = firmer tension — Each maker sets its own weight bands.
- Shop test time (NBF): At least 10 minutes — Lie in your usual sleep position, then turn over.
- Online cancel window: 14 days — Counted from delivery for most distance sales. Trials are shop extras.
- UK King: 150 × 200 cm — Longer than a Double. Narrower than many EU King sizes.

Sources:

- [National Bed Federation — regulations and standards](https://www.bedfed.org.uk/resources/regulations-standards/) — No legal size-tolerance standard. Accepted practice is plus or minus 20 mm on stated length and width. Checked 2026-09-25.
- [IKEA UK mattress size guide](https://www.ikea.com/gb/en/rooms/bedroom/mattress-size-guide-pub63d34391/) — Lists UK standard sizes and extra 80 × 200, 90 × 200 and 140 × 200 lines you must not mix by name alone. Checked 2026-08-28.
- [Vispring — mattress buying guide (tension by body weight)](https://www.vispring.com/guide/mattress-buying-guide/) — One maker's published tension bands by body weight, shown in the table. Checked 2026-09-25.
- [National Bed Federation (Bed Advice) — buying a bed that is right for you](https://bedadvice.co.uk/bed-buyers-guide/buying-a-bed-thats-right-for-you/) — Test for at least 10 minutes. Heavier people need firmer tension. Partners 3 stone apart may need different mattresses. Checked 2026-09-25.
- [National Bed Federation (Bed Advice) — 7 steps to choosing a mattress](https://bedadvice.co.uk/7-steps-in-choosing-the-right-mattress/) — Shop together, the lie-side-by-side space test, and the hand-in-the-back test. Checked 2026-09-25.
- [National Bed Federation (Bed Advice) — advice for children](https://bedadvice.co.uk/beds-and-beyond/bed-and-mattress-advice-for-children/) — Medium feel for children, base suitability, avoiding hand-me-down mattresses and replacing at growth stages. Checked 2026-09-25.
- [GOV.UK — accepting returns and giving refunds](https://www.gov.uk/accepting-returns-and-giving-refunds) — The 14-day distance-sale cancel right, the extra 14 days to return, and the custom-made and sealed-hygiene exceptions. Checked 2026-09-25.

## What should I decide first when I choose a mattress?

Decide in this order. Each step narrows the next one.

1. **Type** — how the core holds you up.
2. **Support** — spring tension or foam firmness for your body weight.
3. **Feel** — how soft the top is, for the way you sleep.
4. **Size** — width and length in centimetres.
5. **Base** — whether your bed base suits the mattress.
6. **Trial and warranty** — what happens if it is wrong.

Soft, medium and firm labels mix steps 2 and 3. Split them, or you compare unlike things. This page is a decision order, not a brand list. We have not slept on any mattress here.

## Step 1: Which mattress type should I start with?

Start with how the core holds you up.

| Type | Good starting point | Skip it if |
| --- | --- | --- |
| [Pocket sprung](/mattresses/pocket-sprung) | Springs in fabric bags. Often kinder for couples. | You want a very light mattress to move alone. |
| [Hybrid](/mattresses/hybrid-construction) | Springs under a thick foam or latex layer | Your slat gaps are wider than the maker allows. |
| [Memory foam](/mattresses/memory-foam) | Slow moulding. Can cut partner movement. | You sleep hot and dislike a “hug” feel. |
| [Latex](/mattresses/latex-talalay-vs-dunlop) | Bouncier foam. Often cooler than memory foam. | You want the slow sink of memory foam. |
| [Open coil](/mattresses/open-coil-bonnell) | Linked springs. Usually lower cost. | Partner movement bothers you. |

See every type side by side in [mattress types compared](/mattresses/mattress-types-overview).

## Step 2: How do I match support to my body weight?

Spring tension means how hard the springs push back. It should suit your weight. The National Bed Federation (NBF) gives a general rule: the heavier you are, the firmer the tension you need.

A heavy sleeper on soft tension can sink too far. A light sleeper on firm tension can feel perched on top.

Makers publish their own weight bands. Here is one example.

| Body weight | Vispring's suggested tension |
| --- | --- |
| Up to 70 kg (11 st) | Soft |
| 70–102 kg (11–16 st) | Medium |
| 102–127 kg (16–20 st) | Firm |
| Over 127 kg (20 st) | Extra firm |

Source: Vispring's mattress buying guide, checked on 25 September 2026. This is one maker's chart. Other makers use different bands and names. A "medium" from one brand may not match another. Always ask for the chart for the exact model.

For foam mattresses, ask about [foam density](/mattresses/foam-density-explained) and firmness. Thickness alone is not support. See [spring tension vs comfort feel](/mattresses/spring-tension-vs-comfort-feel) and [higher body weight support](/care/higher-body-weight-mattress-support).

## Step 3: How should sleep position change the top feel?

Once support is right, pick the top feel.

- **Side sleepers** often want more give at the shoulder and hip.
- **Back sleepers** often want even support without deep sinking.
- **Stomach sleepers** often want less sink so the hips do not drop.

The NBF suggests a simple test. Lie on your back and slide a hand under the small of your back. If it slides in too easily, the bed may be too firm. If you struggle to fit it in, it may be too soft.

See [firmness and sleep position](/mattresses/firmness-and-sleep-position) and the [side](/mattresses/side-sleeper-mattress-guide), [back](/mattresses/back-sleeper-mattress-guide) and [stomach](/mattresses/stomach-sleeper-mattress-guide) guides. If you have pain, ask a GP or physiotherapist. This is not medical advice.

## Step 4: Which UK size do I need?

Use centimetres, not names. A UK Double is 135 × 190 cm. A King is 150 × 200 cm. A Super King is 180 × 200 cm. See [UK standard sizes](/sizing/uk-standard-bed-sizes).

The NBF suggests a space test for couples. Lie side by side with your hands behind your head. Your elbows should not touch. It also notes there is no legal size tolerance. Accepted practice is 2 cm either way.

Measure stairs and doors too. See [footprint and access](/sizing/bed-footprint-and-access).

## Step 5: Will it suit my bed base?

The base can void a warranty if it is wrong. Foam-heavy mattresses often need a firm platform or slats with a small gap. Makers often quote about 7 cm as a maximum. The warranty leaflet wins. See [base compatibility](/care/mattress-base-compatibility) and [how to choose a bed base](/beds/how-to-choose-a-bed-base).

## Step 6: What trial, returns and warranty should I check?

Read three sets of rules before you pay:

- **Trial** — a shop extra that lets you return or swap after sleeping on it. See [mattress trial periods](/care/mattress-trial-periods).
- **Legal rights** — what the law gives you if the mattress is faulty. See [UK bed refund and return rights](/care/uk-bed-refund-and-return-rights).
- **Warranty** — what the maker covers, such as dips deeper than a stated depth. See [mattress warranty explained](/care/mattress-warranty-explained).

## How do I test a mattress in a shop?

The NBF suggests lying on a bed for at least 10 minutes, and longer if you can. Wear comfy clothes. Take off your coat and shoes. Lie in your usual position, then turn over. If the bed is for two, go together. See [how to try a mattress in a shop](/mattresses/how-to-try-a-mattress-in-a-shop) and [questions to ask in a bed shop](/mattresses/questions-to-ask-in-a-bed-shop).

## How do I choose a mattress online without trying it?

You cannot lie on it first. So lean harder on facts and return rules.

1. **Read the layer list.** Note the core, each layer and total depth.
2. **Find the tension or firmness chart.** Check it against your weight.
3. **Check the size in centimetres,** not just the name.
4. **Check the weight and delivery.** Will it arrive rolled? Can you carry it upstairs?
5. **Read the trial terms.** Look for a minimum wait, protector rules and collection charges.
6. **Know your cancel right.** GOV.UK says online buyers can usually cancel within 14 days of receiving the item. They then have another 14 days to send it back.

Custom-made items, such as a special size, can be an exception. Sealed items opened for hygiene reasons can be too. Ask the seller before you order.

## How do I choose a mattress for a child?

Size comes first. Cots, cot beds and bunk beds need a mattress that fits the frame. Bunks often limit mattress depth so the guard rail still works. See the [kids mattress guide](/sizing/kids-mattress-guide).

The NBF suggests a medium mattress. It lets a child change position easily. The NBF also says to check the mattress suits the base, such as slats or mesh.

The NBF advises a new mattress, not a hand-me-down. It also suggests replacing the bed at big growth stages. A tall teenager needs feet on the mattress, not over the end. See [second-hand mattress hygiene](/care/second-hand-mattress-hygiene) and the [kids sizes path](/learn/kids-sleep-sizes).

## How do two people with different needs choose one mattress?

Shop together, and both lie down in your usual positions. Then pick one of these routes:

- **Similar weights, different feel:** a medium tension with a middle top feel can work. Test it together.
- **Big weight gap:** the NBF says partners about 3 stone (18 kg) or more apart may need different mattresses.
- **Two mattresses joined:** [zip-and-link](/mattresses/couples-and-zip-and-link) zips two mattresses into one bed. Each side can have its own tension.
- **One mattress, two halves:** a [split tension mattress](/mattresses/split-tension-and-dual-firmness) has a different tension on each side.

Compare the two in [split tension vs zip-and-link](/compare/split-tension-vs-zip-and-link). Partner movement is a separate question. See [motion isolation](/mattresses/motion-isolation). A topper will not split two support needs.

## Not sure where to start? Try the finder

Our [starting-point finder](/learn/start) asks three quick questions. It points you to one guide or a full learning path. It does not pick a mattress for you. For a guided route, try [buy your first mattress](/learn/first-mattress).

## What should I ignore in the shop script?

Ignore “orthopaedic” as a medical claim — see [what orthopaedic means](/mattresses/orthopaedic-mattress-explained). Ignore a spring count without a size. Ignore matching quizzes as proof — see [how mattress matching quizzes work](/mattresses/mattress-matching-quizzes-explained). Ask construction questions instead.

## Related BedGuide entries

- [Before you buy a mattress](/mattresses/before-you-buy-a-mattress)
- [What’s inside a mattress](/mattresses/whats-inside-a-mattress)
- [How to read a mattress spec](/mattresses/how-to-read-a-mattress-spec)
- [Budget vs premium mattress](/mattresses/budget-vs-premium-mattress)
- [Answers hub](/answers)

## Frequently asked questions

### What is the first thing to decide when buying a mattress?

Pick the support type first — pocket sprung, open coil, foam, latex or hybrid. Then match tension or foam support to your weight. Then pick the top feel for your sleep position.

### Soft, medium or firm — which should I buy?

Those words mix two things. Spring tension should suit your weight. The padding on top decides how plush it feels. Ask about each one on its own.

### What spring tension do I need for my weight?

The heavier you are, the firmer the tension you usually need. Each maker publishes its own weight bands, and they differ. Use the chart for the exact model.

### What size mattress do couples need in the UK?

Many couples prefer a King (150 × 200 cm) or Super King (180 × 200 cm) over a Double (135 × 190 cm). Check sizes in centimetres, not just the name.

### How long should I lie on a mattress in a shop?

The National Bed Federation suggests at least 10 minutes, and longer if you can. Lie in your usual sleep position. Try your side and your back.

### Can I return a mattress bought online?

Online orders usually come with a 14-day right to cancel from delivery. Custom-made items can be an exception. A sleep trial is an extra set by the shop.

### What mattress is best for a child?

Choose the right size for the bed first, especially on cots and bunks. The NBF suggests a medium feel and a new mattress, not a hand-me-down.

### What if my partner and I need different firmness?

Look at zip-and-link, which joins two mattresses, or a split tension mattress. The NBF says a weight gap of about 3 stone or more may need different mattresses.

### Can a topper fix the wrong mattress?

A topper can change how the surface feels. It cannot add real spring support or fix a sagging core. If the tension is wrong, the mattress is wrong.

### What should I ignore in a mattress advert?

Ignore “orthopaedic” as a medical claim and a spring count with no size. Ask for the support type, tension for your weight, size in centimetres and the approved base.

---

Source: https://bedguide.co.uk/mattresses/how-to-choose-a-mattress/ · BedGuide — educational encyclopedia, no affiliate commission. Facts checked against official sources where possible; see https://bedguide.co.uk/editorial-policy. Report an error: https://bedguide.co.uk/corrections.