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18 x 20 Patio Cushions

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Price with selected options

15% Off - Till Stock Lasts
  • Outdoor cushions 18 x 20, designed for long-lasting comfort
  • Weather-, and UV-resistant fabric designed for durability
  • Durable foam filling offers relaxation
  • Variety of fabrics, colors, and patterns available
  • Easy to install, remove, clean, and maintain

Made Right for Everyday Outdoor Seating

When your outdoor furniture needs 18 x 20 outdoor seat cushions, you're working with precise space constraints. These smaller dimensions work perfectly for bistro sets, apartment balconies, and breakfast nook chairs where standard cushions overwhelm the scale. The compact 18 x 20 size provides full seat coverage without hanging over edges or creating bulk that makes small spaces feel cramped. Weather resistant fabric and dense foam construction mean these cushions maintain their comfort and appearance through daily use, turning those hard metal or plastic seats into places people actually want to sit for more than a few minutes.

Use Cases:

  • For dining sets and accent chairs
  • For backyard and poolside furniture
  • Upgrades for seat cushions or bistro chairs 
  • Porch chair, folding chair, or portable seating
  • Replacement outdoor seat cushions for worn-out pads
  • Custom-fit for odd-shaped or hard-to-fit seating
  • Pick from a curated catalogue of performance fabrics built for life outdoors.
  • Available in a range of solids, prints, stripes, and textures
  • Designed to resist fading, moisture, mold, and mildew.
  • Easy to maintain, spot clean or machine wash depending on fabric.

Foam Core Options:

  • Choose the level of support that suits your seating style.
  • Soft, medium, or firm high-resilience foam for lasting shape retention.
  • Add a Dacron fiber wrap for a fuller look and a cushier finish.

Whether you’re updating the cushions on an outdoor pergola setup or redesigning a private patio, 18 x 20 patio chair cushions are the standard size for most outdoor furniture. Pick your ideal fabric, foam density, color, and pattern to create cushions that match your exact vision of an outdoor space that reflects your style. 

Why Choose Our Custom Outdoor Couch Cushions?

  • Perfect Fit, Every Time: These 18 x 20 patio chair cushions are crafted to standard dimensions, so they sit properly on chairs without awkward overhang or gaps that make them look cheap.
  • Weather-Ready: Choose outdoor-rated fabrics built to resist fading, water, and mildew.
  • Comfort That Stays: High-density foam holds its shape through seasons of use.
  • Easy Care: Zip-off covers make maintenance simple.
  • Customizable: Select your fabric, foam firmness, and thickness for a cushion that matches your seating and your lifestyle.
Use Coupon Code

ZIPCUSHION15 - Get 15% Off Sitewide

Frequently Asked Questions

Always measure between the seams or between the cording of the case. Measure the length, width, and thickness of square and rectangular shapes. For round and cylindrical shapes, measure diameter and thickness. Custom cushions require additional measurements based on the type of shape.

18x18 and 18x20 Inches are the medium sizes that work well on most sofas, chairs, and beds, while 20x20 inches is popular for large cushions.

If your backseat is 18 x 20 in dimension, yes. Otherwise, we recommend ordering separate back cushions for a better fit. Back seat cushions should be more comfortable and may have a different thickness than your seat cushions.

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Customer Reviews

Based on 751 reviews
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(675)
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D
Darlene

Excellent quality and fits perfectly . I needed a custom filer cushion for my outdoor set. The support team was so helpful on assisting me with the order.

S
Sam

Awesome in quality and customer support!

M
Marykay Holland (Shawnee, US)
Very Satisfied Customer

My custom made trapezoid cushion was a perfect fit. It was delivered ahead of schedule. They called to verify cushion thickness, and requested I send a photo of the sketch with measurements to recheck. I am very pleased with its appearance and comfort. Great product, carefully constructed and great customer service. I will use again if needed. Thank you. MKHolland Shawnee OK

D
Dena Libner (Portland, US)
fantastic quality

The quality of these cushions are absolutely fantastic, and the selection/purchasing process was seamless. Thrilled to have found ZipCushions!

M
Matina Wielgos (Wood Dale, US)
Perfect custom cushion!

Love my window seat cushion! I ordered a custom size window cushion with piping. Color was exactly what I wanted! Of all the sites I looked at theirs is the most user friendly and clear for customer. I received updates often and it arrived in a timely manner. So pleased!

V
VALARIE

The foam was top-quality..

S
Sherrie

Cushions fit perfectly, well-made, fast shipping!

I
Iana

Exactly the size I requested — the custom dimensions were spot on and it fits perfectly. The quality is excellent: firm, well-shaped, and the material feels durable and well-made. Everything matched my order exactly. Very satisfied with this purchase

L
Lexie Hash (Bel Air, US)
Awesome! So happy with cushion!

Zip Cushions was absolutely amazing to work with. Their team was incredibly thorough and took the time to double check all of my measurements to make sure everything was perfect. I really appreciated the attention to detail and care they put into the process. My new cushion turned out beautifully and fits exactly as I hoped. The quality is excellent and you can tell it was made with precision. Shipping was also very quick which made the whole experience even better. I would highly recommend Zip Cushions to anyone looking for a custom piece done right.

J
Jacquelyne

Perfect fit and fabric. Exactly what I was looking for.