Outdoor Seat Cushions for Chairs 20 x 18 x 3 in - Comfortable Patio

Our review of these outdoor seat cushions focuses on people who want a straightforward, durable upgrade for metal or wooden patio chairs. The single biggest reason to buy is comfort combined with weather resistance: the thick polyurethane foam and a 100% polyester, UV-resistant cover make these cushions both supportive and suitable for regular outdoor use. They arrive compressed, so allow 24 hours for the foam to recover, but once fluffed they provide a firm, stable seat that keeps its shape and color on a sunny patio.

Key Features

• Size: 20 x 18 x 3 in dimensions are designed to fit most dining and bistro chairs but it is important to measure your chair before buying for a correct fit.
• Waterproof and durable cover: The 100% polyester cover is breathable, UV- and fade-resistant to keep the cushion looking fresh outdoors over time.
• Hidden zippered design: A concealed zipper allows for easy cleaning and replacement of the cover while keeping a neat, seamless look on the chair.
• Upgraded foam core: Thick, high-resilience 100% polyurethane foam delivers firm support that relieves pressure and resists permanent compression.
• Secure fit: Non-slip ties and an anti-slip bottom keep the cushion in place so you can sit without sliding on metal or slatted seats.
• Compressed shipping: Cushions arrive compressed and should be left 24 hours after unpacking to regain full shape for lasting comfort.

Who It's For

These cushions are best for homeowners with standard dining or bistro patio chairs who want a firm, dependable seat and a true navy color that resists fading. They work well on metal, wood, or wicker chairs on a deck, patio, balcony, or garden seating area where durability and easy cleaning matter.

Shoppers who need custom-sized or very thick lounge cushions should look elsewhere; if your chair seat differs by more than 0.5 in from the listed dimensions, a different size or custom pad will be a better choice. Also, if you prefer plush, sink-in cushioning, these firmer, high-resilience foam pads may feel too supportive.

Pros & Cons

Pros

• Well-made covers deliver good color accuracy and hold up to sun exposure thanks to UV resistance.
• Thick polyurethane foam offers firm support and maintains shape over time.
• Non-slip ties and anti-slip bottom keep cushions secure during use.
• Hidden zipper makes the cover easy to remove for cleaning without spoiling the look.

Cons

• Arrives compressed and requires about 24 hours to fully expand, which delays immediate use.
• Only one listed size (20 x 18 x 3 in) so it may not fit chairs with dimensions outside the 0.5 in tolerance.

Specifications

Size	20 x 18 x 3 in
Quantity	Set of 2
Cover material	100% polyester (breathable, UV- and fade-resistant)
Foam core	100% polyurethane, high-resilience foam
Attachment	Non-slip ties and anti-slip bottom
Assembly	Required; arrives compressed, allow 24 hours to regain shape

Our Verdict

These cushions are a practical, value-focused choice for anyone who wants a firm, colorfast seat for standard patio chairs. The combination of high-resilience foam, a waterproof polyester cover, and secure ties gives reliable comfort and low maintenance, making them a sensible buy for outdoor dining and casual seating areas.

Frequently Asked Questions

Will these cushions fit my dining chair?
Measure your chair seat and compare to 20 x 18 x 3 in; if the difference is more than 0.5 in the fit may be poor.

Do the covers come off for washing?
Yes, there is a hidden zippered design so the cover can be removed for cleaning or replacement.

How long until the cushions expand after unpacking?
They arrive compressed and should be left about 24 hours to fully regain their shape and firmness.