The most common reason a replacement cushion does not work is size. Listings describe cushions in different ways, some give the cushion size, some the frame size, and a few give both, so measuring your furniture first saves a return.

This guide explains what to measure on each type of patio furniture and how to compare those numbers to a listing. You need a tape measure and a notepad. For roundups that list each maker's sizes, see the Outdoor Cushions category.

Measure the Frame, Then the Old Cushion

Measure the frame where the cushion sits, not just the old cushion. Old cushions compress, shrink and lose shape, so their size can mislead you. If the old cushion still fits well, measure it too and compare the two sets of numbers.

Chairs and Deep Seat Lounge Chairs

  • Width: inside the arms, at the front and at the back. Use the smaller number if they differ.
  • Depth: from the front edge of the seat to the back frame.
  • Back height: from the seat to the top of the back, if you need a back cushion.
  • Thickness: note how much room there is before the cushion would sit above the arms.

See Best Outdoor Deep Seat Cushions and Best Patio Chair Cushions.

Sofas, Loveseats and Sectionals

For a loveseat, measure the full seat length between the arms and the depth. For sectionals, measure one seat module, then count every seat, armless piece and corner. Corner backs are often a different size from standard backs.

Some listings give a fit range for the frame, which is the easiest way to match. See Best Outdoor Loveseat Cushions and Best Outdoor Sectional Cushions.

Chaise Lounges

Lay the chaise flat. Measure the total length, the width inside the frame, and the distance from the foot to the hinge where the back folds. A cushion whose hinge does not line up with the chair's hinge will bunch when you sit up. See Best Chaise Lounge Cushions.

Benches, Swings and Rockers

For benches, measure length between the arms and depth. For porch swings, measure seat length and the back height, since swing listings usually give a combined seat-plus-back figure. For rocking and Adirondack chairs, measure seat depth and the full back height, and note whether there is a gap between seat and back. See bench, porch swing, rocking chair and Adirondack chair cushion guides.

Reading a Listing

  • Check whether sizes are for the cushion or the frame.
  • Look for conflicting numbers between the title and the description, and ask the seller if they disagree.
  • Expect small variation in sewn products. Several makers state a tolerance.
  • Remember that vacuum-packed cushions take one to several days to reach full size.

FAQ

Should a cushion be smaller than the seat?

Usually it should match closely or be very slightly smaller, so it sits flat without gaps or bunching.

What if my measurements fall between sizes?

Choose the size closer to the frame without going over, or look for stretch covers or listings with a fit range.

Do I measure with the old cushion in place?

No. Measure the empty frame, then use the old cushion only as a second check.

The Bottom Line

Measure the empty frame first, write down width, depth, back height and any hinge point, then compare those numbers to the listing. Check whether the listing describes the cushion or the frame, and watch for conflicting sizes. A few minutes with a tape measure prevents most fit problems.