Single vs Small Double Mattress: Which Size Should You Choose?
A single mattress measures 90x190cm (3ft) while a small double measures 120x190cm (4ft). The right choice depends on who will use it, how much floor space you have and whether the bed is for daily teenage sleep, occasional guests or a growing child. First-time buyers, students and parents usually need clear facts on room fit, comfort for two and value before purchasing.
UK Mattress Size Basics
UK single mattresses are 90x190cm. Small double mattresses are 120x190cm, giving 30cm extra width. Both share the same 190cm length, so the decision is mainly about width. EU sizes differ (single 90x200cm, double 140x200cm), so always confirm the exact label when buying UK beds. Cot mattresses are typically 60x120cm and cot bed sizes 70x140cm; these are separate categories.
Who Each Size Suits Best
Single mattresses work well for children under 12, students in compact rooms and occasional adult guests. They suit narrow bedrooms and are easy to manoeuvre up stairs. Small double mattresses better suit teenagers who need more space to spread out, couples who sometimes share a guest room or taller teens who move a lot at night. Parents often choose small double for teenagers who host sleepovers or for multi-use guest rooms.
Practical Checklist Before Buying
- Measure the bedroom floor space allowing at least 75cm clearance on each long side for making the bed.
- Check doorways and stairwells; a 120cm wide mattress needs more turning space than a 90cm one.
- Decide primary user: one child, two children sharing, teenager alone or adult guests.
- Consider future use; a small double can serve longer as children grow.
- Match the mattress to a compatible bed frame – see our kids single beds or small double beds.
Space and Room Fit Comparison
A single bed frame typically needs a floor area of roughly 110cm x 220cm including clearance. A small double needs about 140cm x 220cm. In a 2.5m x 3m student bedroom a single leaves more room for a desk or chair. In a larger teenage bedroom a small double still allows space for storage. Always draw the room to scale before deciding. Bunk beds must meet BS EN 747; top-bunk guard rails must rise at least 16cm above the mattress, so follow the maker’s maximum mattress depth. Top bunks are not recommended for children under 6.
| Feature | Single Mattress | Small Double Mattress |
|---|---|---|
| Width | 90cm (3ft) | 120cm (4ft) |
| Length | 190cm | 190cm |
| Typical users | Child, student, single guest | Teenager, two children, guest couple |
| Floor space needed | Smaller footprint | Extra 30cm width |
| Sharing comfort | Not suitable for two adults | Acceptable for occasional sharing |
Cost and Practical Trade-offs
Small double mattresses and their frames generally cost more than single equivalents because they use more materials. Base prices rise with size, and bedding such as sheets and protectors also costs extra for the wider option. However a small double can avoid the need to upgrade in two to three years as a child grows. Single options remain cheaper for short-term student housing or spare rooms used only a few nights a year. All UK mattresses must meet fire-safety rules under the Furniture and Furnishings (Fire) (Safety) Regulations 1988 and are tested to BS 7177.
Recommended Mattress Types for Each Size
For single beds, a foam or sprung model that is easy to rotate works well. The Noomi Waterproof Eco Foam Mattress Single is ideal for children and teenagers because it is practical and wipeable. For small double, consider memory foam or pocket sprung options that offer more support across the wider surface. Browse our full range of single mattresses or small double mattresses. Pair either with a memory foam mattress if pressure relief is important.
Bed Frame Choices and Storage
Choose a frame that matches the mattress size exactly. Single beds suit narrow rooms and are available in many children’s designs. Small double frames give more sleeping area but require a larger bedroom. Ottoman beds add storage underneath; see single ottoman beds and small double ottoman beds. For teenagers, high sleepers or cabin beds free up floor space for desks. Flair, Noomi and Recoil frames are popular choices that meet current safety standards.
Decision Rules for First-Time Buyers
- If the room is under 9m² choose single to keep circulation space.
- If the user is 13 or older and the room is 10m² or larger, choose small double.
- For guest rooms used by couples pick small double; for single visitors single is sufficient.
- Budget under total? A single mattress and frame is usually the realistic option.
- Plan to keep the bed five years or more? Pay the extra for small double.
Students in shared houses often prefer single because it fits standard small bedrooms. Parents buying for teenagers should measure the existing bedroom and consider how long the child will stay in it. Guest rooms benefit from the extra width of a small double when visitors stay longer than one night.
Our picks for this guide
- Noomi Waterproof Eco Foam Mattress Single – Practical wipe-clean surface and eco foam make it ideal for teenagers or students using a single mattress daily (from £129.99 at Bed Kingdom).
- Flair Wizard Small Double Bed Frame – Simple, sturdy frame that pairs perfectly with a small double mattress for teenagers or guest rooms (from £179.99 at Bed Kingdom).
- Recoil Shuttle LED Gaming High Sleeper Bed Small Double Black – Combines small double sleeping space with a raised design that frees floor area in teenage bedrooms (from £619.99 at Bed Kingdom).
- Flair Tetrad Detachable Small Double Bunk Bed – Meets BS EN 747 safety rules and offers two small double sleeping areas for siblings or sleepovers (from £369.99 at Bed Kingdom).
Frequently asked questions
Can two adults sleep comfortably on a small double mattress?
A 120x190cm small double offers enough width for occasional adult sharing but is not as generous as a standard double (135x190cm). Most couples prefer a full double or king for regular use. It works for short guest stays.
Is a single mattress suitable for a 14-year-old?
Many 14-year-olds still fit a 90x190cm single but taller teens or those who move a lot at night may prefer the extra 30cm width of a small double. Check the teenager’s height and sleeping habits before deciding.
Do single and small double mattresses need different bedding?
Yes. Single sheets and duvets are narrower. Small double requires its own size of fitted sheets, protectors and duvets. Mattress protectors are available to fit both sizes and help keep the mattress clean.
Which size is easier to move up stairs?
A single mattress (90cm wide) is significantly easier to carry around corners and up staircases than a 120cm small double. If access is tight, choose single or buy a mattress that can be rolled.
Are there any fire safety rules for these mattresses?
All upholstered mattresses sold in the UK must comply with the Furniture and Furnishings (Fire) (Safety) Regulations 1988 and are tested to BS 7177. Look for the permanent label that confirms compliance.
Related guides
- Small Single Mattress for Bunk Beds: When to Choose This Size
- Euro Double vs UK Double Mattress: Size and Fit Guide
- Double vs King Size Bed: Which Size Is Right for You?
- 3ft Single Bed vs 4ft Small Double: Which Is Right?
- Best Bed Size for Teenagers: Single or Double
- Small Double Bed Room Size Requirements UK