Key takeaways
- Width — edge to edge across the widest point. For tapered seats (common on wicker and rattan dining chairs), measure the front edge and the back edge separately; a taper of 2 inches or more usually needs a custom or wicker-specific cover.
- Depth — front edge to back edge.
- Thickness — measure the foam itself, then add roughly ½ inch if it’s wrapped in polyester batting, which most outdoor seat foam is.
- Back cushions — these are usually fiber-filled, not foam. Measure seam to seam, then add 1–1.5 inches to the width and height if you want a plump rather than flat look.
What's inside
The right replacement cushion covers for outdoor furniture are sized from the bare foam insert—never from the old cover—and the fabric choice in most climates comes down to solution-dyed acrylic for exposed, full-sun patios versus polyester for covered or budget setups. Everything below walks through the measuring steps, the fabric trade-offs with real numbers, and when zippers beat ties.
Step 1: Measure the Insert, Not the Old Cover
Old covers shrink, stretch, and sag, so measuring them gives you dimensions that are ½–1 inch off in at least one direction. Pull the cover off, let the foam sit uncompressed for an hour, then measure:
- Width — edge to edge across the widest point. For tapered seats (common on wicker and rattan dining chairs), measure the front edge and the back edge separately; a taper of 2 inches or more usually needs a custom or wicker-specific cover.
- Depth — front edge to back edge.
- Thickness — measure the foam itself, then add roughly ½ inch if it’s wrapped in polyester batting, which most outdoor seat foam is.
- Back cushions — these are usually fiber-filled, not foam. Measure seam to seam, then add 1–1.5 inches to the width and height if you want a plump rather than flat look.
Most cover makers recommend an insert that is ½–1 inch larger than the finished cover so the cushion fills out without wrinkles. If your foam is 4 inches thick, order a 4-inch cover—don’t add loft to foam the way you would to fiber.
If the cushions are on the frame, measure the furniture instead: interior width between the arms, rail to seat-back depth, and—if ties are involved—the distance between tie attachment points.
| Furniture piece | Typical footprint | Typical thickness | Measuring notes |
|---|---|---|---|
| Dining chair pad (incl. wicker/rattan) | 16×16 to 20×20 in | 2–3 in | Check for taper; note tie spacing on the frame |
| Deep-seat club chair | 22×22 to 25×25 in | 4–6 in foam | Back pillows usually 6–8 in of fiber loft |
| Wicker/rattan loveseat or sofa | 38–44 in wide (loveseat); 56–72 in (sofa) | 4–6 in | Measure frame interior, not the sagging old cushion |
| Chaise lounge | 21–24 × 72–80 in | 2–4 in | Measure each hinged section plus the hinge gaps |
| Bench / settee | 40–48 in wide | 3–5 in | Rounded fronts need a “bullnose” style cover |
Step 2: Choose Fabric — Solution-Dyed Acrylic vs Polyester
“Solution-dyed” means the pigment is inside the fiber, not printed on the surface, which is why it resists fading. Solution-dyed acrylic (Sunbrella and Outdura are the best-known mills) is the premium option; polyester ranges from genuinely solution-dyed mid-grade fabric down to cheap printed spun polyester that can visibly fade in a single summer of direct sun.
| Fabric | Fade resistance in full sun | Water behavior | Typical price per standard cover | Realistic lifespan outdoors |
|---|---|---|---|---|
| Solution-dyed acrylic | 5–10 yr fade warranties are standard | Sheds light rain, dries fast | $40–$90 stock; $90–$160 custom | 6–10 years |
| Solution-dyed polyester | 2–4 years before noticeable fade | Similar to acrylic, slightly slower drying | $25–$50 | 3–5 years |
| Printed spun polyester | Fades in 1–2 seasons of direct sun | Water-resistant until surface treatment wears | $15–$35 | 1–3 years |
| PU/PVC-coated “waterproof” polyester | Coating often outlasts… nothing—it cracks and peels in 1–3 years | Blocks rain but traps condensation inside | $20–$45 | 2–4 years |
| Olefin | 3–5 years | Good; resists mildew well | $25–$50 | 3–6 years |
The “Waterproof” Catch
Waterproof cushion covers for outdoor furniture sound ideal but create a trade-off: a sealed coating keeps rain out and traps humid air and condensation in, which is exactly what mildew needs. On an uncovered deck in a wet climate, the better-performing combination is a breathable water-resistant woven cover over reticulated (quick-dry) foam, stored on edge during storms. If you do buy coated waterproof covers, look for vented panels or a zip-off design so the inserts can dry, and plan to replace them sooner.
One more color note: black cushions for outdoor furniture hide stains beautifully, but black shows fading fastest in cheap printed fabrics—it turns gray-brown within a season or two. If you want black, solution-dyed acrylic is close to mandatory. Also expect a black cushion in direct sun to run noticeably hotter to the touch than a light color.
Step 3: Zipper vs Tie Closures
- Zippers give the cleanest look and keep covers tight on deep-seat sofas and chaises. The weak point is the zipper itself: metal zips corrode within a season or two near salt air, so look for a #5 resin coil zipper with a fabric flap covering it. A failed zipper on an otherwise good cover means paying for a re-sew or living with a gap.
- Ties are the better call on open-frame wicker and rattan dining chairs, where there’s no seat lip to stop a cushion from sliding. Two ties minimum; four for a full-size seat pad. Measure your frame’s tie spacing or confirm the cover has self-adjusting tie positions. Ties fray and snap over 2–4 years but are cheap to replace; they also suit renters because they adapt to non-standard frames.
- Hybrid covers (zipper body plus corner ties) exist and solve both problems—worth the small upcharge on seat pads that get heavy use.
Match the Cover to Your Situation
| Your situation | Fabric pick | Closure | Why |
|---|---|---|---|
| Uncovered deck, full southern sun | Solution-dyed acrylic | Resin zipper | Only fabric that survives 5+ years of UV |
| Covered porch, tight budget | Printed polyester | Ties or zipper | UV exposure is low; cheap covers last several seasons |
| Humid or rainy climate | Acrylic or olefin, vented | Zipper | Breathability beats “waterproof”; pair with quick-dry foam |
| Wicker/rattan dining chairs | Any, matched to exposure | Ties | No seat lip; cushions slide without anchors |
| Kids, pets, heavy use | Solution-dyed acrylic | Zipper | Machine-washable, bleach-cleanable, abrasion-resistant |
| Renter / one-season fix | Spun polyester | Ties | Universal fit, $15–$35, no commitment |
When a Cover Alone Won’t Fix It
Replacement seat cushions for outdoor furniture (cover plus insert) run about $50–$150 per piece, with deep-seat sets typically $150–$350, versus $15–$50 for a cover alone. Buy the full cushion if the foam fails the press test: push down hard, release, and if it doesn’t spring back within a few seconds, the foam is dead. For replacement foam, look for at least 1.8 lb/ft³ density and a 30–35 ILD firmness for seats; uncovered furniture benefits from reticulated quick-dry foam that drains rather than sponging up rain.
If you own a discontinued collection—Martha Stewart Living patio sets from the mid-2000s are a common example—brand-labeled cushions are no longer produced. The best replacement cushions for outdoor furniture in that case are universal sizes or custom covers built from your measurements. Deep-seat frames on legacy sets most often fall in the 22–25 inch width range, which standard covers usually fit once you’ve measured the frame interior.
FAQ
Should the cover be smaller than the insert?
Slightly, yes. Most makers recommend a foam insert about ½–1 inch larger than the cover so the cushion looks plump. Fiber back pillows want even more oversize—1–1.5 inches.
Do waterproof covers prevent mildew?
No—they often cause it by trapping condensation. In wet climates, breathable covers plus quick-dry foam mildew far less than sealed coatings.
Can I machine-wash outdoor cushion covers?
Solution-dyed acrylic covers generally machine-wash cold and air-dry; many tolerate a diluted bleach solution for mildew. Coated “waterproof” polyester should be wiped or hosed only—machine washing degrades the coating.
What size cover fits a typical wicker chair?
Most wicker dining and porch chairs take a seat pad around 18×18 to 20×20 inches, but wicker frames taper—measure the seat front and back before ordering rather than assuming a square.
