---
title: "Trapezoid Window Seat Cushion Cost: How the Price Is Set"
url: "https://cushionguide.com/answers/trapezoid-bay-window-cushion-cost/"
section: "The Cutting Table"
author: "Hana Lindqvist, The Quiet Geometer of Seattle"
author_url: "https://cushionguide.com/masters/hana/"
published: "2026-07-09"
updated: "2026-07-09"
keywords: "trapezoid window seat cushion cost, bay window cushion price, trapezoid cushion quote, custom bay window seat cushion"
---

# How much does a trapezoid bay window seat cushion cost?

*Two measurements set the price. Three more make it fit. The conversation usually runs in this order.*

Also asked as: How much would a trapezoid cushion cost?; Can I get a quote for my window seat?

> **The quick answer:** A trapezoid window seat cushion's cost is set by two measurements: its depth and its longest length. Select those ranges on the trapezoid listing and the price appears; the low starting price is for the smallest size. For a firm quote, send a drawing with all five A-E measurements and any notches. Piping costs nothing extra.

![Curved black window seat cushion on an oak bay in a green library with a tuxedo cat, olive pillows and a brass arc lamp](https://cushionguide.com/media/bay-window-cushions/curved-black-bay-seat-green-library-tuxedo-cat-1600.webp "A curved black cushion follows an oak bay seat in a green library, with a tuxedo cat asleep on the bend.")

## Key facts

- Trapezoid price uses the depth and the longest length.
- The listing's starting price is for the smallest size.
- A firm quote uses a drawing with A-E measurements, notches included.
- Thickness options are 2, 3, 4 or 5 in (5, 8, 10 or 13 cm).
- Piping is not extra and can be a contrasting color.
- Bays over about 14 ft (4.3 m) are made in two pieces.
- Cover-only trapezoids can be made for foam you supply.

## “Can you just tell me the price?”

Not before two numbers. A [trapezoid cushion](https://cushionguide.com/cushions/trapezoid-cushions/) is priced by its depth and its longest length. Choose those ranges on the trapezoid listing and the price appears.

The low starting price you see first is for the smallest size. Angled shapes also cost more than rectangles. They take more labor.

To test your numbers before you ask, try the [trapezoid cushion calculator](https://cushionguide.com/studio/trapezoid-cushion-calculator/).

## “And for a firm quote?”

1. **Draw the seat from above**: A simple sketch. Front edge at the bottom, wall at the top.
2. **Label A to E**: Front, back, depth, and both angled sides.
3. **Mark any notches**: Where the seat meets a post or casing, draw the cutout with its size.
4. **Choose a thickness**: 2, 3, 4 or 5 in (5, 8, 10 or 13 cm).
5. **Choose the piping**: It is not extra. It can be a contrasting color.

## A bay seat with notches

A buyer in the US sent a bay seat: 70 in (178 cm) along the front, 44 in (112 cm) along the back, 20.5 in (52 cm) deep, with 2.5 in (6.4 cm) notches, at 2 in (5 cm) thick.

Those numbers were enough. Depth and longest length went onto the trapezoid listing, and the price appeared.

## “My bay is long, and I already have foam.”

Bays over about 14 ft (4.3 m) are made in two pieces.

If you already have foam, a cover-only trapezoid can be made for it. Covers are removable and wash at 86°F (30°C). Keep them out of the tumble dryer. The [trapezoid measurements Pattern](https://cushionguide.com/guides/trapezoid-cushion-measurements/) shows where each tape goes.

What does your longest edge measure?

Two numbers set the price.
Five numbers set the fit.
The drawing does both.

> **Tailor's margin:** A trapezoid window seat cushion is priced from depth and longest length; the other three A-E measurements are what make it fit.

> Piping on a trapezoid window seat cushion costs nothing extra, and it can be sewn in a contrasting color.
>
> — Hana

## Buyer questions

**A common question:** How is a trapezoid window seat cushion priced?

**The workshop's answer:** By two measurements, depth and longest length, selected on the trapezoid listing. The low starting price is for the smallest size, and angled shapes cost more than rectangles because they take more labor.

**A common question:** Roughly what would my bay window cushion cost?

**The workshop's answer:** It depends on your A-E measurements, so send a drawing first. Past quotes covered a linen trapezoid about 137 in (3.48 m) along the front and 30 in (77 cm) deep with contrast piping, and a bay over 14 ft made in two pieces. Cover-only versions have been made where the buyer supplied the foam.

**A common question:** What thickness options are there for a trapezoid bay cushion?

**The workshop's answer:** 2, 3, 4 or 5 in. Piping is not extra and can be a different color, and the cover is removable and washable at 86°F (30°C), with no tumble dryer.

**A common question:** Is one long cushion cheaper than several pieces?

**The workshop's answer:** Usually about the same, because price follows total surface. Separate pieces add sewing and zippers, yet real splits came out equal or slightly cheaper.

**A common question:** Does the store sale apply to a custom trapezoid quote?

**The workshop's answer:** Yes. Custom quotes already include the current store sale, even for custom sizes, but codes can't be stacked on top.

## Questions buyers ask next

### What if my seat is smaller than the smallest size option?

Payment is matched to your written size. Below the smallest option, you order that option and the shop refunds anything above its quote; a cushion a few inches shorter than an option has sometimes earned a small partial refund.

### Can I supply my own foam and order only a trapezoid cover?

Yes. Cover-only trapezoids are made for buyer-supplied foam, including one for a bay about 95 in (241 cm) along the front. Send the same A-E drawing, measured on the foam, plus its thickness.

### When does a bay cushion have to be made in two pieces?

When the bay runs over about 14 ft (4.3 m). The two pieces are still sized from your A-E drawing, and the same thickness and piping choices apply to both.

## Related at the atelier

- [How much does a custom trapezoid cushion cost?](https://cushionguide.com/answers/trapezoid-cushion-cost-quote/): A custom trapezoid cushion has no fixed price: it is quoted from the length of every side (back, front and both angled sides), the thickness, the fabric and whether it is part of a set.
- [My cushion is bigger than the largest size option. Can I still order it?](https://cushionguide.com/answers/cushion-larger-than-listed-sizes/): Yes, a cushion bigger than the largest size option can still be ordered, through a custom purchase link.
- [Trapezoid Bench Cushion in Hibiscus Print: A Daily Wear Test](https://cushionguide.com/readings/tropical-hibiscus-trapezoid-cushion-canal-house-bay/): A dark, busy print is the most forgiving cover for a trapezoid bench cushion in a family bay window: red and orange hibiscus on navy hide drips and paw marks that a pale plain fabric would show.
- [Trapezoid Bench Cushion in Mudcloth on a Floating Oak Bay Seat](https://cushionguide.com/readings/mudcloth-trapezoid-cushion-floating-oak-bay-seat/): A trapezoid bench cushion in a bay reads well from across the room when its shape and contrast are right: angled ends that follow the side walls, a straight front edge, and a dark field against pale…
- [Trapezoid Bench Cushion in Terracotta: Notes from the Bay](https://cushionguide.com/readings/terracotta-trapezoid-window-seat-knit-olive-pillows/): A trapezoid bench cushion is measured as a list of lengths: front, back, depth and each angled side, plus any short corners.
- [Every cushion shape, drawn once, with the numbers it needs](https://cushionguide.com/guides/cushion-shapes-chart/): Cushion shapes fall into a few families: rectangles and squares, angled shapes such as trapezoids and clipped corners, polygons, corner runs (L, U, T), notched seats, curves, and traced shapes.
- [How to measure a trapezoid cushion so the numbers close](https://cushionguide.com/guides/trapezoid-cushion-measurements/)
- [Making a paper template a cushion workshop can actually use](https://cushionguide.com/guides/paper-template-for-custom-cushion/)

*— Hana*

---

Written by Hana Lindqvist (https://cushionguide.com/masters/hana/) 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/answers/trapezoid-bay-window-cushion-cost/