Key takeaways
- Width: straight across the seat at its widest point, usually the front edge. On chairs with arms, measure between the arms, not outside them.
- Depth: from the front edge of the seat to where the seat meets the backrest.
- Back taper: the width at the back of the seat. Many metal and resin dining chairs are 2 to 3 inches narrower at the back than the front, which is why so many cushions are trapezoid-shaped (for example 19 inches at the front and 16 or 17 inches at the back).
A 16 x 16 inch outdoor chair cushion fits small bistro chairs, folding café chairs and many armless dining chairs whose seat measures 16 to 17 inches across, but it will look undersized on most standard patio dining chairs, which usually need an 18 x 18 or 19 x 19 inch pad. The quickest way to know is to measure the flat part of your seat, not the overall chair, and compare it to the size chart below.
Measure the Seat, Not the Chair
Cushion sizes are listed as width x depth, and they describe the cushion itself. To match one to your chair, measure three things with a tape:
IASEAHK Patio Chair Cushions, 18.5" x 16" x 3" Outdoor Chair Cushions Set of 4, Waterproof Outdoor Cushions for Patio Furniture, Outdoors Seat Cushions with Handle and Ties, Navy Blue
Included for '16 x 16 Outdoor Chair Cushions: Which Chairs They Fit and When to Size Up' because the listing specifies 18.5" x 16" x 3" Outdoor Chair Cushions Set of 4 and Waterproof Outdoor Cushions for Patio Furniture, details this guide uses to compare options.
View on Amazon
Pillow Perfect Paisley Indoor/Outdoor Chairpad with Ties, Reversible, Tufted, Weather, and Fade Resistant, 15.5" x 16", Blue/Multi Pretty, 2 Count
Included for '16 x 16 Outdoor Chair Cushions: Which Chairs They Fit and When to Size Up' because the listing specifies Reversible and Tufted, details this guide uses to compare options.
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Pillow Perfect Tropic Botanical Indoor/Outdoor Tufted Wicker Seat Cushion With Ties, 2 Count, 15.5" x 16", Green Swaying Palms Capri
Included for '16 x 16 Outdoor Chair Cushions: Which Chairs They Fit and When to Size Up' because the listing specifies 2 Count and 15.5" x 16", details this guide uses to compare options.
View on Amazon- Width: straight across the seat at its widest point, usually the front edge. On chairs with arms, measure between the arms, not outside them.
- Depth: from the front edge of the seat to where the seat meets the backrest.
- Back taper: the width at the back of the seat. Many metal and resin dining chairs are 2 to 3 inches narrower at the back than the front, which is why so many cushions are trapezoid-shaped (for example 19 inches at the front and 16 or 17 inches at the back).
As a rule, a cushion should be the same size as the seat or up to half an inch smaller on each side. A cushion that overhangs by more than an inch tends to droop at the front and collect water at the edges; one that is 2 or more inches smaller slides around and leaves a visible frame border.
Outdoor Chair Cushion Size Chart
These are the common square and near-square sizes sold for patio chairs, and the seat each one typically suits.
| Cushion size (W x D) | Best for seat width | Typical chairs | Common thickness |
|---|---|---|---|
| 16 x 16 in | 15.5 to 17 in | Bistro chairs, folding café chairs, small metal dining chairs | 2 to 3 in |
| 16 in round | 15 to 17 in round seat | Round-seat bistro chairs and bar stools | 2 to 3 in |
| 16 x 18 in | 16 to 17 in wide, 17.5 to 19 in deep | Narrow but deep dining chairs, some sling chairs | 2 to 4 in |
| 18 x 18 in | 17.5 to 19 in | Standard aluminum and resin dining chairs | 2 to 4 in |
| 19 x 18 in | 18.5 to 20 in wide, 17.5 to 19 in deep | Wider dining chairs with a shallow seat | 2 to 4 in |
| 19 x 19 in | 18.5 to 20 in | Larger dining chairs, many wicker and wrought iron chairs | 3 to 4 in |
| 19 x 20 in | 18.5 to 20 in wide, 19.5 to 21 in deep | Deep dining chairs, armchair-style dining seats | 3 to 4 in |
| 20 x 20 in | 19.5 to 21 in | Club-style dining chairs, rocking chairs, wide wicker seats | 3 to 4 in |
| 20 x 20 x 3 in | 19.5 to 21 in | Same chairs, with a firmer, lower-profile pad | 3 in |
When 16 x 16 is the right call
Classic two-person bistro sets, French-style folding steel chairs and compact balcony chairs often have seats between 15 and 17 inches wide. A 16 x 16 pad fills them neatly without hanging over the rails. It is also the right size when the seat is rounded at the front: a square 16-inch pad sits inside the curve rather than poking out at the corners.
When to size up
If your seat measures 17.5 inches or more, a 16-inch cushion will leave a gap of nearly an inch on each side and shift every time someone sits down. Move to 18 x 18 for seats around 18 inches, 19 x 19 or 19 x 20 for seats around 19 inches, and 20 x 20 for anything wider. If the depth is noticeably larger than the width, choose a rectangular size such as 16 x 18 or 19 x 20 rather than a bigger square.
Thickness and Fill: What Changes Comfort Most
Size gets the cushion to fit; thickness and fill decide whether it is still comfortable after one season. On small bistro chairs, thick cushions raise you higher above a table that is already low, so 2 to 3 inches is the sweet spot. On deeper dining chairs, 3 to 4 inches gives more support without changing table height much.
| Fill type | Feel | Drying time after rain | Typical lifespan outdoors |
|---|---|---|---|
| Polyester fiberfill | Soft, pillowy; flattens with use | Many hours to a day | 1 to 2 seasons |
| Polyurethane foam slab | Firm and even | Slow if soaked; holds water | 2 to 4 seasons |
| Foam core wrapped in fiber | Supportive with a soft top | Moderate | 3 to 5 seasons |
| Reticulated (open-cell) quick-dry foam | Firm, slightly springy | Drains in minutes to an hour | 4 or more seasons |
For 16 x 16 cushions, which usually go on chairs left outside on balconies and small patios, quick-dry foam is worth the extra cost if the chairs are not covered. Fiberfill cushions are cheap and comfortable but tend to develop a flat center within a summer of daily use.
Fabric Choice for Small Chair Cushions
Fabric is where the price gap shows. Solution-dyed acrylic, the category that includes Sunbrella, holds color for years in direct sun and resists mildew; it is common on cushions priced around $35 to $80 each. Spun or printed polyester is far cheaper, often $10 to $25 per cushion, but printed patterns fade within one or two summers in full sun. Olefin sits in between, with good fade resistance at a moderate price.
If the cushions will live in full sun on a south- or west-facing balcony, solution-dyed fabric pays for itself by not needing replacement. Under a covered porch, polyester is usually fine.
Ties, Straps and Keeping Small Cushions in Place
Light 16-inch cushions blow off chairs in a breeze more easily than heavier 20-inch pads. Look for:
- Back ties: two fabric ties at the rear corners that wrap around the back legs or uprights. Check that the ties are long enough for your frame; 10 to 12 inches is typical.
- Non-slip backing: a rubberized bottom panel helps on smooth aluminum and resin seats.
- Hook-and-loop straps: handy on chairs with no vertical uprights to tie to, such as some folding bistro chairs.
Round 16-Inch Cushions
A 16-inch round cushion is the standard answer for round-seat bistro chairs and many backless bar stools. Measure the seat diameter edge to edge through the center. For round seats, a cushion equal to the seat or half an inch smaller looks best; a square cushion on a round seat leaves corners hanging off and is easy to knock loose. Round pads usually have a single center tie or none at all, so a non-slip bottom matters more here.
Quick Fit Guide by Situation
| Your situation | Size to choose | Thickness |
|---|---|---|
| Two-seat balcony bistro set, 16 in seat | 16 x 16 or 16 in round | 2 in |
| Standard aluminum dining set, 18 in seat | 18 x 18 | 3 in |
| Wrought iron or wicker chair, 19 in seat | 19 x 19 or 19 x 20 | 3 to 4 in |
| Wide rocker or club dining chair, 20 in seat | 20 x 20 or 20 x 20 x 3 | 3 to 4 in |
| Seat narrower at back than front | Trapezoid cushion matching front and back widths | 2 to 3 in |
Care and Storage
Small cushions are easy to bring in, and that is the single biggest factor in how long they last. Stand them on edge after rain so water drains out of the foam. Brush off pollen and dirt before it bakes into the fabric, and spot-clean with mild soap and water. Over winter, store them dry in a deck box or closet; a set of four 16 x 16 x 2 inch cushions stacks into a space roughly 16 inches square and 8 to 10 inches tall.
Common Questions
Can I use 18 x 18 cushions on a 16-inch seat?
You can, but expect about an inch of overhang on every side. On a chair with arms or vertical uprights, the cushion will bunch against them. It works better on armless chairs with a flat front edge.
Do 16 x 16 cushions fit bar stools?
Many square-seat outdoor bar stools have 15 to 17 inch seats, so a 16 x 16 pad often fits well. Measure first, because some stools have 13 to 14 inch seats that need a smaller pad.
