Here's a confession from the sofa cover industry: the number one reason covers get returned isn't quality, colour, or fabric — it's fit. A cover that's too small won't reach the arms. One that's too large bunches, sags, and slips every time someone sits down. And the cause of bad fit is almost always the same: someone guessed.
This guide will show you exactly how to measure your sofa for a cover, step by step, so you get it right the first time. Whether you have a standard 2-seater, an L-shaped corner sofa, a recliner, or a Chesterfield, we'll walk you through the measurements that matter.
What You'll Need
Before you start, gather these tools:
- A soft tape measure (the kind used for dressmaking, not a metal builder's tape — metal can scratch your sofa)
- A notebook and pen (or your phone's notes app)
- A helper (optional but useful for larger sofas — holding the tape straight across a 3-seater is easier with two pairs of hands)
- 10 minutes of uninterrupted time
That's it. No special equipment, no professional installer. Measuring your sofa is genuinely simple once you know which numbers matter.
The Four Measurements That Matter
There are four key dimensions you need to know. Let's take them one at a time.
1. Total Width (Seat-to-Seat)
This is the single most important measurement. It determines which size category your cover falls into.
How to measure: Measure from the outer edge of one armrest to the outer edge of the other armrest, straight across the front of the seat. Keep the tape measure level and straight — don't follow the contours of the cushions.
Write it down: "Total width: ___ cm"
Why it matters: Sofa covers are sized by total width. A standard UK 2-seater is typically 140–180 cm, a 3-seater is 180–220 cm, and a 4-seater is 220 cm+. Knowing this number lets you filter quickly when shopping.
2. Seat Depth
How to measure: Measure from the front edge of the seat cushion to the back of the sofa (where the back cushion meets the frame). If your seat cushions are removable, measure from the front edge of the sofa frame to the back.
Write it down: "Seat depth: ___ cm"
Why it matters: Seat depth determines whether a cover will bunch at the front or pull too tight across the seat. Most UK covers accommodate seat depths of 50–70 cm, but if yours is outside that range, you'll need to pay special attention to stretch-fit options.
3. Arm Height and Arm Depth
How to measure:
- Arm height: Measure from the top of the armrest to the seat surface.
- Arm depth: Measure from the front edge of the arm to where it meets the back of the sofa.
Write it down: "Arm height: ___ cm, Arm depth: ___ cm"
Why it matters: Arms are where covers struggle most. If a cover doesn't have enough fabric to wrap the arms, it rides up and exposes the armrest — which is often the first place to show wear. High, wide arms (like on a Chesterfield) need covers with generous arm dimensions.
4. Back Height
How to measure: Measure from the top of the seat cushion to the highest point of the sofa back.
Write it down: "Back height: ___ cm"
Why it matters: The back height determines whether the cover will drape properly over the back of the sofa. A cover that's too short for the back will look like a badly-fitted sheet. Too tall, and you'll have excess fabric to tuck.
How to Measure Different Sofa Types
Different sofa shapes need slightly different approaches. Here's how to handle the common UK sofa types.
Standard 2-Seater and 3-Seater Sofas
This is the easiest. Take all four measurements above and you're done. Most covers are designed for these standard shapes, so as long as your total width falls within the product's stated range, you'll get a good fit.
Pro tip: If your width falls right at the boundary of two sizes (e.g., your sofa is 180 cm and the sizes are "160–180 cm" and "180–210 cm"), go for the larger size. Stretch fabrics can accommodate slight excess, but they can't stretch beyond their maximum.
Corner Sofas and L-Shaped Sofas
Corner sofas need a slightly different approach because they're essentially two sofas joined at an angle.
- Measure each section separately. Treat the main body and the chaise/corner section as two separate measurements. Note the width of each section.
- Add them together for the total width if you're buying a single-piece cover. For separate covers (one for each section), use the individual measurements.
- Measure the depth of the chaise section separately — it's often deeper than the main seat.
Many of our covers come in corner-specific sizes. Check the full collection and filter by corner sofa options.
Recliner Sofas
Recliners are tricky because the moving parts mean the sofa's shape changes. Here's the key: measure in the closed (upright) position. The cover needs to fit when the footrest is down and the back is upright. When the recliner opens, the cover will stretch — that's what stretch fabrics are designed for.
Also measure the gap between the seat back and the wall — you need enough clearance for both the reclining mechanism and the cover fabric. Our recliner sofa cover collection is specifically designed for these mechanisms.
Armchairs
Armchairs follow the same four-measurement system, just on a smaller scale. The key difference: arm width is proportionally larger on an armchair relative to total width, so pay extra attention to arm dimensions.
For a deep dive on armchair covers specifically, see our armchair covers UK guide.
Chesterfield Sofas
Chesterfields present unique challenges: low backs, high rolled arms, and deep tufting. The rolled arms in particular need generous arm depth measurements — measure from the front of the arm roll to where it meets the seat back, following the curve.
We've written a complete Chesterfield sofa cover guide that covers the nuances in detail.
Common Measuring Mistakes to Avoid
Over hundreds of customer queries, the same measuring mistakes come up again and again. Here are the top five:
Mistake 1: Measuring Cushion Width Instead of Sofa Width
The total width is armrest-to-armrest, not cushion-to-cushion. Two seat cushions on a 200 cm sofa might each be 85 cm — but that's irrelevant. You need the full 200 cm.
Mistake 2: Forgetting to Account for Cushion Thickness
If your seat cushions are unusually thick (some modern sofas have 20 cm+ cushions), the cover needs extra depth to wrap around them. Check whether the cover's stated seat depth range accommodates your cushion thickness, not just your frame depth.
Mistake 3: Not Measuring the Back Height
People focus on width and forget the back. If your sofa has a tall back (75 cm or more), a standard cover may not reach over it — leaving the top of the back exposed.
Mistake 4: Measuring in Inches and Converting Wrongly
If you're shopping on a UK site that uses centimetres (as most do), measure in centimetres. Don't measure in inches and convert — the rounding errors can push you into the wrong size bracket. One inch off either way is the difference between a cover that fits and one that doesn't.
Mistake 5: Measuring with Cushions Removed
Unless you plan to remove your seat cushions every time you put the cover on, measure with the cushions in place. The cover goes over the whole sofa, cushions included.
What to Do If Your Measurements Fall Between Sizes
This is the most common scenario, and the answer is simple: always size up.
Stretch sofa cover fabrics (typically a polyester-spandex blend with 5–15% spandex) can comfortably accommodate 5–10 cm of excess fabric. They cannot, however, stretch beyond their stated maximum. If your sofa measures 185 cm and the size options are "160–180 cm" or "180–210 cm," go with the larger size. The slight excess can be tucked into the crevices between seat and back, or anchored with a sofa gripper pad for a smooth, taut fit.
For more on keeping covers from slipping once fitted, see our guide on how to stop sofa covers slipping.
Quick Reference: UK Sofa Size Guide
Here's a quick reference table for common UK sofa types:
| Sofa Type | Typical Width Range | Cover Size to Look For |
|---|---|---|
| Armchair | 80–120 cm | Armchair / 1-seater |
| 2-seater | 140–180 cm | 2-seater |
| 3-seater | 180–220 cm | 3-seater |
| 4-seater | 220–260 cm | 4-seater |
| Corner sofa | 240–320 cm | Corner / L-shape |
| Recliner 2-seater | 160–200 cm | Recliner 2-seater |
Note: These are typical ranges. Always check the specific product's size guide before ordering.
FAQ
Q: Do I need to measure my sofa with or without cushions on it?
A: Measure with the cushions in place. The cover goes over the entire sofa, including seat cushions. The only exception is if you're buying separate cushion covers rather than a full sofa cover.
Q: What if my sofa is an unusual shape — not a standard 2-seater or 3-seater?
A: Measure all four dimensions (width, seat depth, arm height/depth, and back height) and use a stretch-fit cover with a wide size range. Stretch fabrics accommodate unusual shapes better than fitted styles. If your sofa is truly non-standard, contact the retailer — many offer custom sizing.
Q: How accurate do my measurements need to be?
A: To the nearest centimetre. You don't need millimetre precision, but rounding up or down by more than 2 cm can push you into the wrong size bracket. Use a soft tape measure and measure twice to confirm.
Q: Can I use a cover that's slightly too big for my sofa?
A: Yes, and this is preferable to one that's too small. Excess fabric can be tucked into crevices and anchored with a gripper pad. A cover that's too small will leave arms or back exposed and pull uncomfortably tight across the seat.
Q: How do I measure a corner sofa for separate covers?
A: Treat each section as a separate sofa. Measure the width, seat depth, and back height of each section independently. The corner section (or chaise) typically has a different depth than the main body — measure both.
Q: Does the thickness of my seat cushions affect the cover size I need?
A: Yes. If your cushions are particularly thick (20 cm or more), you may need to size up to ensure the cover wraps fully around them. Check the product's stated seat depth range and compare it to your frame depth plus cushion thickness.
