Measuring a couch for a cover requires three core dimensions taken at the couch’s widest points: total width (armrest to armrest), total depth (front to back), and height (floor to backrest top), plus a check against the cover brand’s specific size chart.
Buying a couch cover that actually fits starts with the tape measure, not the shopping cart. A cover that’s too small won’t stay on, and one that’s too large bunches and slides. The fix is simple but specific: use the right measuring method for the cover style you’re buying. The table below breaks down the two most common fit systems, and the steps that follow walk through every measurement.
The Two Ways Cover Brands Size Their Products
Cover manufacturers use one of two sizing approaches. You’ll need to know which one your chosen brand follows before you start measuring.
| Fit System | What You Measure | Best For |
|---|---|---|
| Total outer dimensions | Outer edge of left arm to outer edge of right arm (width); furthest front to furthest back (depth); floor to top of backrest (height) | Most stretch-fit covers and outdoor furniture covers; brands like Coverstore use this method |
| Seat-width matching | Distance between the inner arms (seat width only), then match to a seat-width chart | Some slipcover brands that size by seating area rather than overall sofa footprint |
Check the product page or size guide for the cover you’re considering before you measure. Using the wrong system guarantees a poor fit.
The Three Measurements That Matter
For most stretch-fit covers, you need three numbers. Move the couch away from the wall so the tape measure can reach all sides, and remove any loose cushions or throws that could throw off the reading. Use a flexible fabric tape measure rather than a rigid metal one — it follows curves and corners better.
Width: Measure left to right at the widest point of the sofa. This is usually across the outer edges of both armrests. If the arms flare outward, measure at their widest flare. Do not measure cushion-to-cushion — that will give you a seat width that’s inches too small.
Depth: Measure from the very front edge of the seat (include any cushion overhang or attached pillow backs) straight back to the rear edge of the backrest. Keep the tape level and straight; don’t follow the curve of the cushion.
Height: Measure from the floor straight up to the top of the backrest or the highest point of the sofa frame. If the backrest has attached pillows or a rounded top, measure to the actual highest point.
Write down all three numbers and compare them directly to the manufacturer’s size chart. A couch that measures 86 inches wide × 38 inches deep × 34 inches tall might match a “Large” from one brand and an “XL” from another — see our top-rated couch cover recommendations here.
Extra Measurements for Specific Styles
Not every sofa fits the three-number formula. Add these when your couch or cover type requires them:
- Sectionals and L-shapes: Measure each section separately — left-arm piece, right-arm piece, corner wedge, and chaise — following the brand’s sectional measuring instructions. Never assume one section’s dimensions represent the whole piece.
- Recliners: If your sofa has reclining seats, measure the fully reclined length from the front edge of the footrest to the furthest rear point. A cover sized for the upright position may be too short when the footrest is extended.
- Skirts and dust ruffles: Some slipcover brands ask for the floor-to-seat height to ensure the skirt touches the floor evenly. If your sofa has legs longer than about 3–4 inches, add this measurement.
- Outdoor furniture covers: Add 1–2 inches to each dimension for ease of installation and removal. Include attached pillow backs and cushion thickness in both depth and height.
The single most common mistake is measuring along a curve rather than pulling the tape straight across the widest point. Another is assuming one brand’s “large” matches another’s. Always measure fresh for the cover you’re buying, and always check the size chart.
Once you have your numbers, you’re ready to match them to a cover that fits your couch and your budget — the right measurement is the first step to a cover that stays in place and looks like it was made for the sofa.
FAQs
Do I need to include the armrests in my width measurement?
Yes, for most stretch-fit covers that wrap around the arms. Measure from the outermost edge of one arm to the outermost edge of the other. Only skip the arms if the cover brand specifically instructs you to measure seat width between the arms instead.
How do I measure a sectional couch for a one-piece cover?
Measure each connected seat section separately — width, depth, and height for each. Compare each section’s dimensions to the brand’s sectional size chart. A one-piece cover for a sectional is rare; most sectionals require a cover per piece or a multi-piece set designed for the layout.
Should I add extra inches to my measurements for shrinkage?
Not on your end. Measure the couch as it sits. Cover manufacturers build allowance for fabric stretch and slight shrinkage into their size charts. The exception is outdoor furniture covers, where brands recommend adding 1–2 inches per dimension for ease of putting the cover on and taking it off.
References & Sources
- Coverstore. “How to Measure a Sofa or Loveseat” Provides total outer-dimension measuring method for stretch-fit covers.
- IKEA. “How to Measure a Sofa Cover” Offers detailed seat-width and combined-dimension measuring guidance.
- Wayfair. “How to Measure for a Slipcover” Covers multi-point measuring, arm-inclusive sizing, and common mistakes.