18x18 Outdoor Chair Cushions

An 18″ × 18″ cushion fits many dining chairs, both indoor and outdoor. These are some of the most searched chair cushion sizes, but chair seats vary a lot, and many taper toward the back. We make every chair cushion to your exact measurements, including tapered and rounded-front seats.

Build an 18″ × 18″ chair cushionCover only
Cut within ±0.5″Free shippingShips in 2–3 weeksLifetime price match
At a glance

18″ × 18″ chair cushions

Usually fitsDining chairs

Fits many dining chairs, both indoor and outdoor.

Thickness2″–3″

2″ for dining chairs, 3″ for more padding. Up to 8″ is possible.

AttachTies

Matching-fabric ties at the back corners are standard. Velcro on request.

Measure

Check your size

Measure the seat at its widest point side to side, then front to back.
If the back of the seat is narrower than the front, note both widths; we can cut a tapered (trapezoid) cushion.
Note where the chair uprights are so ties sit in the right place. See the measuring guide.
How it works

Order in three steps

1

Open the builder. Your 18″ × 18″ size and a 2″ thickness are filled in; change anything you need.

2

Choose Sunbrella fabric, foam and ties. Not sure on color? Order a swatch.

3

We cut within ±0.5″ and ship in 2–3 weeks, with free shipping.

Other sizes

Shop by size

22″ × 22″24″ × 24″25″ × 25″26″ × 26″27″ × 27″28″ × 28″17″ × 17″18″ × 18″18″ × 20″All sizes
FAQ

Questions

Is 18x18 a standard dining chair cushion size?

It is common, but chair seats vary by brand. Measure your seat and enter the exact size.

My seat is wider at the front. Can you match it?

Yes. Order a trapezoid cushion with the front and back widths.

Can I order a set?

Yes. Order one cushion or a full set; there is no minimum order.