Your child has outgrown the cot bed, the spare room needs a proper mattress for when your parents visit, or you’ve moved into a flat where the bedroom only fits a single. Single mattresses are the forgotten category — most reviews focus on doubles and kings, leaving you scrolling through Amazon listings with identical descriptions and wildly different prices trying to work out if the £89 option is a bargain or a mistake.
The good news: a quality single mattress costs less than you’d expect. The best ones rival double mattresses for comfort and support — they’re just narrower. After testing several for a guest bedroom renovation, the differences between brands at the same price point were surprisingly large. Spending 20 minutes researching before buying saves you from sleeping badly for years.
In This Article
- Single Mattress Sizes Explained
- Best Single Mattresses Overall
- Best for Children
- Best for Guest Rooms
- Best Budget Single Mattresses
- Mattress Types Compared
- What Firmness for a Single Mattress
- Single Mattress Buying Checklist
- Frequently Asked Questions
Single Mattress Sizes Explained
UK single mattress sizes aren’t quite as standard as you’d think:
- Standard UK single: 90cm x 190cm (3ft x 6ft 3in) — fits most single bed frames. This is what you want unless you know otherwise.
- Small single: 75cm x 190cm (2ft 6in x 6ft 3in) — for narrow spaces, bunk beds, and children’s cabin beds. Check your frame before ordering.
- Long single: 90cm x 200cm (3ft x 6ft 6in) — for taller sleepers. Less common but available from most major brands.
- EU single: 90cm x 200cm — the same as a UK long single. Relevant if you’ve bought a bed frame from IKEA (which uses EU sizing). Our mattress sizes guide covers all UK sizes in detail.
Always measure your bed frame before ordering. A standard single mattress in a small single frame won’t fit, and returning a mattress is never fun.
Best Single Mattresses Overall
Best Overall: Emma Original Single (about £250, emma-mattress.co.uk)
Emma’s flagship mattress shrunk to single size loses nothing in quality. The three-layer foam construction (Airgocell for breathability, memory foam for pressure relief, HR foam for support) provides the same comfort as the double and king versions. The cover is removable and washable at 60°C, which matters more for a child’s mattress or guest bed than you’d think.
At £250 before discounts (Emma runs sales constantly — you’ll rarely pay full price), it’s the best all-round single mattress in the UK. 100-night trial, 10-year warranty. Available direct from Emma and through Amazon UK.
Best Pocket Sprung: Simba Hybrid Single (about £300, simbasleep.com)
If you prefer springs to all-foam, the Simba Hybrid combines 2,500 titanium pocket springs with Simba’s Simbatex foam layer. The springs respond individually to pressure, providing excellent support for different body weights — making it adaptable across kids, teens, and adults without feeling too firm or too soft for any of them. We’ve previously compared pocket sprung mattresses in detail if you want the full technology breakdown.
Best Value Premium: Brook + Wilde Lux Single (about £280, brookandwilde.com)
Brook + Wilde let you choose your firmness at the point of ordering — soft, medium, or firm. This is unusually flexible for a boxed mattress brand and means you can match the mattress to the primary user rather than compromising on medium. The Lux uses a 2,000-spring unit with three foam layers. Premium feel, mid-range price. Free delivery and a 200-night trial — the longest in the industry.
Best for Children
Best for Kids: Silentnight Healthy Growth Miracoil (about £120, argos.co.uk)
Designed specifically for children aged 3+. The Miracoil spring system provides zoned support that adapts as children grow, with firmer support in the centre and softer edges. The mattress is treated with Purotex — a hypoallergenic finish that reduces dust mite allergens by up to 42%. At £120, it’s the best children’s single mattress under £150.
Available from Argos, Very, and Amazon UK. The Healthy Growth range comes in standard and small single sizes.
Best Budget for Kids: Silentnight Safe Nights Essentials Cot Bed Mattress (about £60)
For the smallest children transitioning from cot to single, this basic spring mattress provides adequate support at minimum cost. Replace it after 2-3 years as the child grows — a child’s mattress takes more punishment than an adult’s.
What Children Need From a Mattress
- Medium-firm support — children’s spines are still developing. Too soft allows poor alignment; too firm causes pressure points on lighter bodies.
- Hypoallergenic materials — children are more susceptible to dust mite allergies. Look for anti-allergy treatments or encasements.
- Waterproof protector — not optional. Accidents happen. A waterproof mattress protector (about £10-15) saves the mattress from stains and extends its life.
- Breathability — children overheat easily. Open-coil or pocket-sprung mattresses breathe better than dense memory foam.
The Lullaby Trust provides safe sleep guidance for babies and young children, including mattress firmness recommendations.
Best for Guest Rooms
Best Guest Room Mattress: Eve Light Single (about £180, evemattress.co.uk)
A guest mattress needs to be comfortable enough for visitors but doesn’t need the same longevity as a daily-use mattress. The Eve Light is a simpler, thinner version of the Eve Original — two foam layers instead of three, adequate support for occasional use, and a lower price point. It won’t rival the Emma or Simba for nightly sleep, but for 20-30 nights a year of guest use, it’s more than sufficient. Understanding the difference between mattress-in-a-box brands helps you pick the right level for your needs.
Budget Guest Option: Dormeo Memory Classic Single (about £130, dormeo.co.uk)
Memory foam on a budget. The Dormeo compresses well for a boxed mattress, expands within 24 hours, and provides decent pressure relief. Not the most breathable (memory foam traps heat), but for occasional guest use, this is a minor issue. Available from Dormeo direct and Amazon UK.
The Guest Room Hack
If your guest room doubles as an office or playroom, consider a trundle bed or daybed with a single mattress. The mattress stays made up and ready; the bed frame tucks away or functions as a sofa during the day. A 15cm-deep foam mattress (like the Eve Light) works better than a thick pocket sprung in trundle frames because it needs to fit within the frame’s depth limit.
Best Budget Single Mattresses
Under £100: Silentnight Essentials Miracoil (about £90, argos.co.uk)
The cheapest single mattress worth buying. Silentnight’s Miracoil spring system provides decent support, the quilted cover is comfortable against the skin, and the build quality is solid for the price. It’s a no-frills mattress that does the job for guest rooms, children’s beds, and student accommodation. Available at Argos, Tesco, and Amazon UK.
Under £150: IKEA ÅKREHAMN (about £120, ikea.com)
IKEA’s foam mattresses are consistently good value. The ÅKREHAMN is a medium-firm all-foam mattress with a 25-year guarantee — the longest warranty of any mattress at this price. IKEA mattresses use EU sizing (90cm x 200cm), so check your bed frame dimensions. Available in-store and online.
Under £200: Nectar Single (about £190, nectarsleep.co.uk)
Nectar offers the most aggressive trial and warranty in the UK market — 365-night trial and a lifetime warranty. The mattress itself is a solid three-layer foam construction with good pressure relief. At £190 for a single, it’s excellent value for a premium-feeling mattress. If you don’t like it after 11 months, you can still return it.
Mattress Types Compared
Memory Foam
Pros:
- Excellent pressure relief
- Moulds to body shape
- Minimal motion transfer
Cons:
- Retains heat (hot sleepers beware)
- Initial off-gassing smell
- Slow to respond to position changes
Best for: adults who sleep in one position, people with joint pain
Pocket Sprung
Pros:
- Breathable and responsive
- Good edge support
- Suits all sleeping positions
Cons:
- Heavier than foam
- More expensive at comparable quality
- Can be noisy over time
Best for: restless sleepers, people who sleep hot, shared beds
Hybrid (Foam + Springs)
Pros:
- Combines pressure relief of foam with breathability and support of springs
Cons:
- Most expensive option
- Heavier than foam-only
Best for: people who want the best of both, those who can’t decide between foam and springs
Open Coil (Bonnell)
Pros:
- Cheapest option
- Reasonable support for the price
Cons:
- Less targeted support
- More motion transfer
- Shorter lifespan
Best for: budget buyers, guest rooms, temporary use
What Firmness for a Single Mattress
For Children (3-12)
Medium-firm. Children’s growing spines need proper alignment without excessive softness. Most children’s mattresses are designed medium-firm by default. Avoid very soft memory foam for children under 8 — they’re too light to compress it properly and end up sleeping on the surface without the support benefits. If your child’s mattress came with a specific tog bedding setup, matching firmness and warmth creates the most comfortable sleep environment.
For Teenagers
Medium. Teenagers are heavier than children but still growing. A medium mattress accommodates the rapid weight and height changes of adolescence without needing replacement every year.
For Adults in Guest Rooms
Medium. When different people of different sizes will use the mattress, medium is the safest bet. It’s the compromise that works for the widest range of body types.
For Adults as Primary Sleeper
Match firmness to your sleeping position:
- Back sleepers — medium to medium-firm
- Side sleepers — medium to medium-soft (need more pressure relief at hip and shoulder)
- Stomach sleepers — firm (prevents the pelvis sinking and straining the lower back)
Bed Frame Compatibility
Slatted Bases
Most single bed frames use wooden slats. For foam and hybrid mattresses, slats should be no more than 7cm apart — wider gaps allow the mattress to sag between slats, reducing support and comfort. If your frame has wider gaps, add a bunkie board (a thin solid panel, about £20-30 from Amazon UK) between the slats and mattress.
Platform Beds
Solid platform beds (no slats, just a flat surface) work well with all mattress types. The solid base provides consistent support. The only consideration is breathability — put a few books under the mattress corners periodically to air the underside and prevent moisture buildup.
Bunk Beds and Cabin Beds
Bunk beds have maximum mattress depth limits — typically 15-18cm. Check your bunk bed’s specifications before ordering. Many premium mattresses are 22-25cm deep and won’t fit safely in a bunk frame. The Silentnight Healthy Growth range is specifically designed at 18cm depth for bunk bed compatibility.
IKEA Frames
IKEA bed frames use EU sizing (90cm x 200cm), which is 10cm longer than a standard UK single (90cm x 190cm). A UK single mattress in an IKEA frame leaves a gap at the foot. Either buy an IKEA mattress or source a UK long single (90×200) from brands that offer it — Emma, Simba, and Silentnight all do.
Single Mattress Buying Checklist
Buying a mattress online without testing it sounds risky, but the 100-365 night trial periods offered by most boxed brands make it essentially risk-free. If it doesn’t work, you send it back. What matters more is knowing what to look for before you order so the first one is the right one. Before you buy, run through these questions:
- What size bed frame do you have? (Standard 90×190, small 75×190, EU 90×200)
- Who’s sleeping on it primarily? (Child, teen, adult, guest)
- How often will it be used? (Nightly = invest more; occasional = save money)
- Any specific needs? (Allergies, back pain, hot sleeper)
- What’s your budget? (Under £100, £100-200, £200-300)
- Does the brand offer a trial period? (Try before you commit — 100+ nights is standard)
Frequently Asked Questions
What is the best single mattress for a child? The Silentnight Healthy Growth Miracoil (about £120) is our top pick for children aged 3+. It provides zoned support for growing bodies, hypoallergenic treatment for dust mite reduction, and comes in both standard and small single sizes. Pair it with a waterproof mattress protector.
How often should you replace a single mattress? Every 7-10 years for an adult’s daily-use mattress. For a guest room mattress used 20-30 nights a year, it can last 10-15 years. For a child’s mattress, replace every 3-5 years as they grow — a mattress that suited a 5-year-old won’t provide proper support for a 10-year-old.
Are boxed mattresses good enough for daily use? The best ones (Emma, Simba, Nectar) are excellent for daily use and rival traditional mattresses at similar price points. The convenience of vacuum-packing and home delivery doesn’t reduce quality — it reduces retail and logistics costs, which is why boxed brands offer longer trials.
Can adults sleep comfortably on a single mattress? Yes — a standard UK single (90cm wide) is comfortable for a solo adult of average build. Larger adults or restless sleepers may find it tight. The mattress quality matters more than the width for comfort — a good single mattress sleeps better than a cheap double.
Do I need a mattress protector? Yes, always. A protector extends mattress life by preventing sweat, spills, and dust mites from reaching the mattress itself. For children’s beds it’s essential. Waterproof protectors from Silentnight or Slumberdown cost £10-15 and are worth every penny.