How Much Backing Fabric for a Throw Quilt?
A throw quilt is the most common everyday project, and the backing is the easiest layer to miscalculate. If you are asking how much backing fabric for a throw quilt, the short answer for a standard 50 by 60 inch throw is about 3.5 yards of 42-inch quilting cotton pieced, or 1.75 yards of 108-inch wide backing in one piece. The rest of this guide walks through the math so the number makes sense for your exact quilt.
What Counts as a Throw Quilt
A standard throw quilt measures 50 inches by 60 inches. Some quilters build a larger "throw" at 55 by 65 or 60 by 72 inches for extra drape over a couch or chair. The backing math below uses the 50 by 60 size, then a reference table extends it to the larger 60 by 72 throw. Always measure your finished top before cutting — pieced tops often finish a half inch or more off the planned size.
Step 1: Add Backing Overage
The backing must be larger than the quilt top so your machine has room to hold and quilt the edges. The planning default is 4 inches per side:
- Backing width = quilt width + (4 × 2) = 50 + 8 = 58 inches
- Backing length = quilt length + (4 × 2) = 60 + 8 = 68 inches
So your backing rectangle for a 50 by 60 throw is 58 by 68 inches. Longarm quilters may ask for 6 to 8 inches per side, which pushes the cut closer to 62 by 72 inches — buy extra if you are sending the quilt out.
Step 2: Count the Panels
A 44-inch quilting cotton yields about 42 inches of usable width after trimming selvages. The 58-inch backing width needs two 42-inch widths sewn side by side, so you will piece 2 panels. A 108-inch wide backing covers the full 58 inches in a single piece, so it needs just 1 panel.
Worked Example: Backing Yardage
For a 50 by 60 throw (58 by 68 backing):
| Fabric width | Panels | Backing yardage |
|---|---|---|
| 42-inch usable cotton | 2 | 3.5 yd planning (2 × 68" = 136" ÷ 36 ≈ 3.8; buy 4 yd to be safe) |
| 108-inch wide backing | 1 | 1.75 yd (68" ÷ 36 ≈ 1.9; buy 2 yd) |
Throw Quilt Backing Reference Table
| Throw size | Backing cut (4"/side) | Pieced 42" | Wide 108" |
|---|---|---|---|
| 50×60 | 58×68 | 3.5 yd | 1.75 yd |
| 55×65 | 63×73 | 4 yd | 2 yd |
| 60×72 | 68×80 | 4.5 yd | 2.25 yd |
Pieced vs. Wide Backing
Pieced 42-inch cotton is the budget choice and the most common. You sew two widths together, press the seam open, and the center seam sits under the quilt. Wide 90-inch or 108-inch backing removes that seam and saves an hour of piecing, which many quilters prefer for a gift throw. If your top has a directional print or you want a seamless back, wide backing is worth the premium. Either way, buy a little extra for shrinkage and crooked cuts.
Frequently Asked Questions
How much backing fabric do I need for a 50 by 60 throw quilt?
With 4 inches of overage per side, cut backing to 58 by 68 inches. That needs 2 panels of 42-inch cotton (about 3.5 yards planning, or 4 yards to buy safely), or 1 piece of 108-inch wide backing (about 1.75 yards).
Should I piece backing or buy wide backing for a throw quilt?
A 50 by 60 throw fits 108-inch wide backing in one piece, which removes the center seam. 42-inch cotton needs two panels sewn side by side. Wide backing costs more per yard but saves piecing time.
How much overage should I add to throw quilt backing?
Use 4 inches per side (8 inches total across) for domestic quilting, and 6 to 8 inches per side if your longarm quilter requires extra gripping room.
Will one width of fabric back a 50 by 60 throw?
No. One 42-inch width covers only part of the 58-inch backing width, so you need two panels. Only 90-inch or 108-inch wide backing covers a throw in a single piece.