---
title: "Custom Window Seat Cushions: Measuring, Thickness and Fabric"
url: "https://cushionguide.com/cushions/window-seat-cushions/"
section: "The Cushion Atlas"
author: "Rosa Delgado, The Porch Keeper of Savannah"
author_url: "https://cushionguide.com/masters/rosa/"
published: "2026-01-06"
updated: "2026-09-24"
keywords: "window seat cushion, custom window seat cushion, window bench cushion, window seat cushion with piping, thin window seat cushion, long window seat cushion"
---

# Custom window seat and window bench cushions for the sunniest seat in the house

*Every house has one seat the dog claims by noon, and it is usually under a window. The cushion has to fit wall to wall, take the sun and survive the nap. Here is how buyers got theirs right, and the one time it went sideways.*

> **The quick answer:** A window seat cushion is a foam seat cut to the exact wall-to-wall length and depth of your window seat. The standard is 4 in (10 cm) thick; 2 or 3 in suits narrow seats under a low sill so the window still opens. Write every spec, thickness included, in the order's personalization note, and choose a fabric that can take daily sun.

![Long mustard window seat cushion with self piping on a white paneled base, border terrier asleep in warm afternoon sun](https://cushionguide.com/media/window-seat-cushions/mustard-window-seat-cushion-border-terrier-afternoon-sun-1600.webp "Mustard carries the sunlight along the whole length of the seat and hides the terrier's wheaten coat.")

## The seat everybody fights over

The first thing I notice in a window seat photograph is never the cushion. It is who is asleep on it. In our lead photo a border terrier has taken the long mustard cushion for the afternoon, and that tells you how a **window seat cushion** really gets used.

A window seat is a reading spot, a nap spot, a street-watching spot and often a lid over the mittens. Window seats come up again and again: bedroom niches, dormers, old paneled seats with drawers underneath.

If yours is angled or spans several windows, go to [bay window cushions](https://cushionguide.com/cushions/bay-window-cushions/). If it doubles as a book corner, the [reading nook cushions](https://cushionguide.com/cushions/reading-nook-cushions/) hub has bolsters and back pillows.

## Window seat numbers, wall to wall

|   |   |
|---|---|
| Length x depth | The true wall-to-wall size, to the nearest 1/4 in; the workshop cuts to the numbers you write |
| Standard thickness | 4 in (10 cm) |
| Under a low sill | 2 or 3 in (5 or 7.5 cm) so the window still opens; 2 in is the sensible minimum for sitting |
| Very long seats | Usually split into equal pieces, such as 92 in (234 cm) as two 46 in cushions; one piece on request |
| Size not in the dropdown | Pick the closest option, then write exact size, thickness, fabric and piping code in personalization |
| Cover | Zippered and removable, hidden on the back edge against the wall |

## Straight, notched, or following an arch

Most window seats are plain rectangles, boxed and piped. When a casing or a wall return pokes into the seat, the cushion gets a notch: draw it with its size and position, as in [notched cushions](https://cushionguide.com/guides/notched-cushion-cutouts-posts-casings/).

Curves are another animal: trace them on paper rather than guessing. An arched window seat has been made that way, as a rectangle plus an arc of a circle, and the [paper template Pattern](https://cushionguide.com/guides/paper-template-for-custom-cushion/) walks you through it.

For the edge, a box edge with piping is the classic window look. Self piping, cut from the cushion's own fabric, keeps a stripe unbroken; a buyer in the US got it on a 94.75 in (241 cm) beige stripe, longer than any listed size, by writing the stripe's own code as the piping color.

## Fabric for a seat in the afternoon sun

Kids and dogs are the real quality control, and on a window seat the sun is the third inspector. Choose for the life the seat leads.

- [Linen and cotton-linen](https://cushionguide.com/fabrics/linen-and-cotton-linen/): soft and lived-in. One reading-nook seat paired forest green linen with mustard piping.
- [Velvet](https://cushionguide.com/fabrics/velvet/): wipes easily and glows in low light. A 25 x 17 in (64 x 43 cm) beige velvet seat was called magnificent on arrival.
- [Striped cotton and ticking](https://cushionguide.com/fabrics/striped-cotton-and-ticking/): stripes run front to back because the roll is about 55 in (140 cm) wide, so a long striped piece needs a seam.
- [Performance and pet-friendly weaves](https://cushionguide.com/fabrics/performance-and-pet-friendly/): for the seat the terrier owns. Tight, washable, mid-tone.

Before you choose a deep color for your sunniest window, read [will a window seat cushion fade?](https://cushionguide.com/guides/window-seat-cushion-fading-sun/)

## Thickness, and why the window gets a vote

Four inches is the standard, and most buyers keep it. The foam is high-density, firm and non-sagging; it is not memory foam.

Go thinner when the window says so. On a narrow seat under a low sill, 2 or 3 in keeps the sash clear. Give your absolute maximum height including the cover, because thin foam has to be cut evenly to the cover or it bulges past your limit. Thinner than 2 in can be made, but it gives too little support to sit on.

Curious how firm 4 in feels? Try the [foam firmness finder](https://cushionguide.com/studio/foam-firmness-finder/), then read [window seat cushion thickness](https://cushionguide.com/guides/window-seat-cushion-thickness/).

## The reorder that arrived 2 inches thin

A buyer in the US ordered a long window seat cushion, 79.25 x 11 in (201 x 28 cm), in linen with pink piping. It arrived, and she realized she had typed the wrong depth. So she reordered at 79.25 x 23.25 in (201 x 59 cm) in a lighter linen with the same piping, and the workshop confirmed by message that it would be 4 in thick like the first.

It arrived 2 in thick. Production had followed the order description, not the chat.

I tell that story at every kitchen table I can, neighbor. The message thread is a conversation. The order note is the instruction.

## Window seat mistakes I've watched good people make

- ✗ Confirming thickness in a chat message instead of the order note. Production reads the order.
- ✗ Measuring once, in the middle. Old walls wander; measure back and front edges and both diagonals.
- ✗ Cutting a narrow cushion exactly to a smooth seat with nothing to grip. Ask for ties or a non-slip base.
- ✗ Asking the maker to weave a custom pattern. Cushion makers cut and sew; choose from the fabric charts.
- ✗ Picking pale linen for the seat the dog lives on. Choose a tight, washable, mid-tone weave with a zip-off cover.

> The workshop cuts from the order note, not the chat. Put the window seat cushion's thickness in the personalization box, or 4 in can arrive as 2 in.
>
> — Rosa

## Dressing a window seat, and where to start

Look through the gallery and you'll see how little a window seat needs. A moss green cushion with mustard gold piping and one leather pillow. Navy ticking with navy piping under a brass sconce. A cream and taupe stripe fitted wall to wall in a bedroom niche, with nothing but dried grass in a vase.

My porch rule works at the window too: two pillows at the ends, one throw, and room for a person. What's the first thing that lands on your window seat every evening?

Before ordering, read [how to measure a window seat in an older home](https://cushionguide.com/guides/how-to-measure-window-seat-cushion/) and, for long seats, [one piece or two](https://cushionguide.com/guides/long-bench-cushion-one-piece-or-two/). The [3D bench cushion builder](https://cushionguide.com/studio/bench-cushion-builder/) previews length, thickness and piping.

> **Tailor's margin:** Under a low window sill, a 2 or 3 in window seat cushion keeps the sash clear. Give the maker your maximum height including the cover.

## Buyer questions

**A common question:** My window seat size isn't in the dropdown. How do I order it?

**The workshop's answer:** Pick the option your size falls into, or the closest one, usually the next size up; the dropdown only sets the price. Then type your exact size, thickness, fabric code and piping code into the personalization box. The workshop always cuts to that note, and fractions like 57 5/8 x 15 3/8 in are fine.

**A common question:** How thin can the cushion be so my window still opens over it?

**The workshop's answer:** For a narrow seat under a window, 2 or 3 in is the usual suggestion, and 2 in (5 cm) cushions have been made so the window above still closes. Thinner is possible but gives little support. Give your absolute maximum including the cover; the thickness is confirmed with you before production.

**A common question:** My window seat is almost 8 feet long. One cushion or two?

**The workshop's answer:** Long seats are usually recommended as equal pieces, for fit, durability and easier handling: a 92 in (234 cm) seat went as two 46 in cushions. Each piece is added to the cart at its own size. It's still your choice, and long one-piece seats have been made on request.

**A common question:** My window seat has a rounded end. How do I measure it?

**The workshop's answer:** Send the total width and depth, the straight length of each edge before the curve starts, and where each curve starts and ends, sketched and photographed. For tricky curves, trace the seat on wrapping paper, cut it out and photograph it flat beside a tape measure. A curve can't be read from numbers alone.

**A common question:** How big is the box for a long window seat cushion?

**The workshop's answer:** Much smaller than the cushion, because long foam cushions are vacuum-compressed before boxing. A 111.5 x 34 in (283 x 86 cm) window seat cushion shipped in a package of about 24 x 20 x 8 in (60 x 50 x 20 cm). If space matters, ask for your order's package size.

**A common question:** Can I see a photo of my cushion before it ships?

**The workshop's answer:** Usually, yes. Ask in messages and the finished piece is photographed before it goes to the courier; for custom shapes the workshop sends final-check photos with measurements and waits for your approval. Changes are still possible at that stage, though a photo depends on the day's production schedule.

## Before you measure the window

### Can two window seat cushions in one order be different colors?

Yes. Add each cushion to the cart at its own size and write its fabric and piping code in that item's personalization note, so each cushion's instructions travel with it.

### Does the fabric I pick change the price of a window seat cushion much?

Not much. Window seat cushions are quoted mainly by size: the price rises with length times depth and with thickness, so an 8 to 9 in cushion sits well above a standard 3 to 4 in one. Angled ends cost a little more than a plain rectangle.

### Can a window seat cushion be tufted with buttons?

Yes. Tufted, French-mattress style cushions are priced by size on their own listing; choose the size closest to yours and write the exact measurements and fabric color in personalization. Long, thin tufted pieces can take a single row of buttons down the center.

### How tall should a back cushion be above a window seat?

Standard backrests are about 16 in (40 cm) tall and 4 in (10 cm) thick, measured from the top of the seat cushion and made the same length as the seat. The workshop recommends 16 in over 12 in for support. A very long soft back, such as 88 in, works better as two 44 in pillows.

### Is there a wipe-clean fabric for a window seat?

Velvet wipes easily, and every standard fabric's cover washes on a gentle cycle at 86°F (30°C). Faux leather is available for a little more if you want a true wipe-down surface; ask to see those fabrics before you order.

### How deep is a typical window seat, and how high should it sit?

Most window seats are 18 to 24 in deep and 36 to 72 in wide. With the cushion on, a comfortable seat sits about 16 to 21 in off the floor, close to a chair's 18 to 19 in. Guides also suggest keeping the seat top a few inches below the window's lower edge. Measure your own seat, though, since built-ins vary widely.

### Do back pillows make a window seat feel shallower?

Yes. Back pillows can take roughly 4 in off the usable depth, so a 20 in seat feels more like 16 in once they lean against the wall. The workshop's standard back cushion is about 16 in tall and 4 in thick. On a shallow seat, choose thinner backs or a single flat lumbar instead of a row of plump squares.

## Related at the atelier

- [Window Seat Cushion in Forest Green: Where to Spend and Save](https://cushionguide.com/readings/forest-green-window-seat-cushion-mustard-piping/): On a custom window seat cushion, spend on the seat: a box edge cut to the full depth of the window box, flush to the wall and front, with piping that outlines a dark color.
- [Emerald Chevron Window Seat Cushion: Built for a Full House](https://cushionguide.com/readings/emerald-gold-chevron-window-seat-cushion-oak-bench/): A long window seat cushion seats guests best when it is cut to the exact length of the seat, with a directional print like an emerald chevron running lengthwise and pillows kept to the ends so the…
- [How thin can a window seat cushion be so the window still opens?](https://cushionguide.com/answers/thin-window-seat-cushion-under-windowsill/): A window seat cushion can be made as thin as 3/4 in (2 cm), but 2 in (5 cm) is the thinnest recommended for sitting.
- [How much does a custom window seat cushion cost?](https://cushionguide.com/answers/custom-window-seat-cushion-cost/): A custom window seat cushion is priced by its size: send the length, depth and thickness, and the workshop sends a quote that shows the shipping cost.
- [How to measure a window seat cushion when the walls aren't square](https://cushionguide.com/guides/how-to-measure-window-seat-cushion/): To measure a window seat cushion in an older home, take the width at the front edge and along the back wall, then the depth at the left end, middle and right end, all from the face of the trim and…
- [Mid-century window seat cushions for long, low ranch ledges and lounge chairs](https://cushionguide.com/concepts/mid-century-window-seat-and-lounge-chair-cushions/): A mid-century window seat cushion should be long, low and ordered a hair under the ledge.
- [Why mildew grows under a window seat cushion in winter, and what helps](https://cushionguide.com/guides/window-seat-cushion-mildew-condensation/)

*Porch light's on — Rosa*

---

Written by Rosa Delgado (https://cushionguide.com/masters/rosa/) for CushionGuide (https://cushionguide.com/about/). The site explains made-to-measure cushions and the partner workshop makes them; measurements are in inches first. This Markdown mirrors the page at https://cushionguide.com/cushions/window-seat-cushions/