The short answer
For a standard UK king bed, a 240 × 300 cm rug is a dependable starting point when placed beneath the lower two-thirds of the bed. A 200 × 290 cm rug can work in a tighter room; a 270 × 360 cm rug creates a more generous, fully anchored layout.
Try the Rug Size CalculatorWhy 240 × 300 cm often works
A UK king mattress is approximately 150 × 200 cm, although the complete bed frame can be wider and longer. A 240 × 300 cm rug allows roughly 45 cm of exposed rug at each side when centred beneath a 150 cm mattress. That is enough for most people to step onto comfortably in the morning.
Placing the rug under the lower two-thirds of the bed leaves the headboard and bedside tables directly on the floor. This saves rug area where it provides little practical benefit and makes positioning easier in rooms with tight bedside clearances.
Three useful king-bed layouts
The lower-two-thirds layout is the most adaptable: run the 240 cm width across the bed and slide the rug forward until its head edge sits roughly level with the front of the bedside tables, about a third of the way up the bed. A fully anchored layout places the whole bed and bedside tables on a larger rug, which suits spacious bedrooms and creates a calm, hotel-like zone.
For a narrow room, two runners—one at each side—can provide the same soft landing without placing a large rug beneath a heavy frame. A smaller rug across the foot of the bed is decorative but may not reach the spots where feet naturally land.
- 200 × 290 cm: compact lower-bed coverage where side clearance is limited.
- 240 × 300 cm: balanced starting point for many king beds.
- 270 × 360 cm: generous coverage, sometimes including bedside tables.
Measure the frame and room together
Measure the widest and longest points of the complete frame, not only the mattress label. Upholstered wings, sleigh ends and chunky side rails can add meaningful centimetres. Then mark the proposed rug outline using low-tack painter’s tape.
Check that wardrobe doors and room doors open freely. Aim to preserve a visible border of floor around the rug; in many rooms 20–45 cm looks deliberate. If the rug edge falls close to a walking route, make sure it will not create a trip point.
Choose material and pile with daily use in mind
A low- or medium-pile rug is easier to slide beneath a bed and vacuum around. Thick pile feels luxurious but can catch doors and make heavy furniture harder to move. A non-slip underlay helps keep exposed edges stable, particularly on smooth flooring.
Before buying, check the retailer’s actual size tolerance. Handmade and natural-fibre rugs can vary slightly from their listed dimensions. That is usually harmless, but worth allowing for beside fitted furniture.
This guide is general information to help you plan, not professional advice. Check product instructions and your supplier's guidance before you buy, and ask a qualified professional about structural or safety-related work. See our terms of use.