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Fabric Shrinkage and Prewashing Guide

Cotton shrinks the first time it is washed, and that shrinkage can throw off a carefully planned quilt. Understanding how much to expect helps you decide whether to prewash and how much extra fabric to buy.

How Much Does Cotton Shrink?

Most quilting cotton shrinks 1 to 3 percent, and up to 5 percent on the first hot wash. That means a 44 inch wide fabric can lose about 1 to 2 inches of usable width after washing, which matters when you are cutting strips WOF.

To Prewash or Not

Prewash if you want the finished quilt to be machine washable without surprise shrinkage, or if you are mixing fabrics with different care needs. Skip prewashing for a crisper handle and when using precuts, which fray badly if washed.

Planning for Shrinkage

If you do not prewash, add about 1/4 to 1/2 inch to each cut dimension or buy roughly 10 percent extra yardage so the finished quilt still meets its planned size after the first wash.

Shrinkage at a Glance

Fabric widthAfter 3% shrinkAfter 5% shrink
44" bolt~42.7"~41.8"
42" usable~40.7"~39.9"
10 yd yardage~9.7 yd~9.5 yd

Frequently Asked Questions

How much does quilting cotton shrink?

Most quilting cotton shrinks 1 to 3 percent, and up to 5 percent on the first hot wash. That means a 44 inch wide fabric can lose about 1 to 2 inches of usable width after washing.

Should I prewash fabric before quilting?

Prewash if you want the finished quilt to be machine washable without surprise shrinkage, or if you are mixing fabrics with different care needs. Skip prewashing for a crisper handle and when using precuts.

How does shrinkage change yardage planning?

If you do not prewash, add about 1/4 to 1/2 inch to each cut dimension or buy roughly 10 percent extra yardage so the finished quilt still meets its planned size after the first wash.

How do I prewash without fraying?

Use a delicate cycle with cold water, add a color catcher for dark fabrics, and either serge the cut edges or wash pieces inside a mesh laundry bag to limit fraying.

Cutting & measuring

Tools that make fabric math easier

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Acrylic quilting ruler

Essential for accurate fabric cutting. Look for non-slip and clear grid lines.

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Rotary cutter (45mm)

Fast, clean cuts through multiple layers. Replace the blade when it skips threads.

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Self-healing cutting mat

Protects your work surface. Get the largest size your space allows.

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Pre-cut fabric bundle

Coordinated fat quarters or jelly rolls, ready to piece straight out of the pack.

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Fabric marking pen

Water-soluble or heat-erasable options. Test on a scrap first.

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Flat-head quilting pins

For pinning layers before basting. Extra-long pins help with thick sandwiches.

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