Quilt Backing Fabric

Quilt backing fabric, cut in one piece

The back of a quilt is half of it, and it is the half nobody plans until the top is finished. This is where the backing fabrics live: wide cuts of 100% cotton that go under a quilt without a seam down the middle, plus everything you need to work out how much to buy.

What wide back fabric is

Standard quilting cotton comes off a 44 or 45 inch bolt. Once the selvedges are gone you have about 42 usable inches, which backs a baby quilt and nothing larger. For anything bigger you buy two lengths, join them, match the print across the join, press the seam open, and then hope the longarm does not land on it.

Wide backing fabric skips all of that. It is woven on a wider loom, most commonly at 108 inches, so a single uncut piece goes right under a queen. Some mills weave 118 and 120 inch, which is as wide as quilting cotton is normally made, but 108 is the width the trade settled on and the one you will find most prints in.

One 108 inch piece is the equivalent of about 7.2 yards of regular width cotton, which is worth remembering when you compare a price per yard and think the wide one looks dear.

How much quilt backing fabric do you need

The rule is simple: add eight inches to each dimension of the finished top, four inches of overhang on every side. Longarm quilters ask for that margin because the frame needs something to grip, and a back cut exactly to size is a back that comes up short once the quilting draws it in. If you are quilting it yourself on a domestic machine you can get away with six, but eight costs almost nothing and saves the whole project.

Working from 108 inch wide backing:

A 3 yard cut of 108 inch backing is the workhorse. It measures 108 by 108 and covers a top up to roughly 92 by 92 with the allowance built in, which is most throw, twin and queen quilts in one seamless piece. A king is the one size that still wants a seam, but one instead of three.

What makes a good backing

Weight first. A backing much heavier than the top fights the quilt sandwich and makes the whole thing hang stiff. A backing much lighter lets the batting shadow through. Standard quilting cotton on both faces is the safe answer, and it is why most backing fabrics are exactly that.

Then the print. A busy or mottled print hides everything: the quilting stitches, the tension that went slightly off in the third row, the join if you had to make one. A flat solid does the opposite and shows every line as a hard scratch across the cloth. Tonals sit in the middle, which is why so many quilters keep coming back to them. If your quilting is meant to be admired, use a quiet backing. If it is meant to be forgiven, use a busy one.

Color last. A dark backing behind a pale low contrast top will shadow through the batting and dull everything above it. A white backing shows every mark the years put on a quilt. Grays and warm neutrals are neutral for a reason.

Can you use a bed sheet

People do, and it is not forbidden, but there is a reason quilters warn each other off it. A sheet is woven with a much higher thread count than quilting cotton, and that density makes it hard to needle. Hand quilters find it heavy going, domestic machines skip stitches, and longarm quilters will often refuse it outright or charge extra. Sheets also come with a hem and a fold line that never presses out. If the quilt is a picnic blanket, use the sheet. If it is going to be quilted properly, use backing fabric.

Prewash or not

Cotton shrinks two or three percent in the first wash. The question is whether you want it to happen before or after the quilting. If you prewash the top you must prewash the backing too, because a shrinking back under an unshrunk top pulls the quilt out of square. If you prewash neither, everything shrinks together and gives you the soft crinkle most quilters are after. What you must not do is prewash one and not the other. Strong colors are the exception: a saturated red or a deep navy is worth washing first whatever you do with the rest.

Press before you load. A backing that has been folded in a parcel has a crease in the middle, and a crease under a longarm becomes a tuck.

What we stock

108 inch wide quilt backing fabric in 3 yard cuts, in tonals that hide the stitching and go under almost any top, plus wider cotton by the yard in our Fabric by the Yard collection for quilts under 55 inches wide. Cut and shipped from our own warehouse.