Quick answer: for a 90 × 108 inch queen quilt with 4 inches of extra backing on each side, buy 8¼ yards of standard 42-inch quilting cotton and sew it with horizontal seams, or 3¼ yards of 108-inch wide backing with no seams at all. Vertical seams would need 9¾ yards, a full 1½ yards more.
Step 1: Work out the backing size
Backing must be larger than the quilt top so it doesn't come up short during quilting. Longarm quilters usually ask for 4 inches extra on every side; if you're quilting on a home machine, 2 to 3 inches is often enough.
For a 90 × 108 inch top with 4 inches per side:
- Width: 90 + 4 + 4 = 98 inches
- Length: 108 + 4 + 4 = 116 inches
Step 2: Compare the two seam directions
Standard quilting cotton gives about 42 usable inches once the selvages are trimmed, so a 98-inch-wide backing needs several panels sewn together. There are two ways to arrange them.
Vertical seams: panels run the full 116-inch length, side by side.
- Panels needed: 98 ÷ 42 = 2.33, so 3 panels
- Fabric: 3 × 116 in = 348 in = 9.67 yd → buy 9¾ yards
Horizontal seams: panels run across the 98-inch width, stacked top to bottom.
- Panels needed: 116 ÷ 42 = 2.76, so 3 panels
- Fabric: 3 × 98 in = 294 in = 8.17 yd → buy 8¼ yards
Both layouts use three panels, but horizontal panels are shorter, so they save 1½ yards. At $12 a yard, that's $18 saved just by turning the seams.
| Option |
Panels |
Fabric to buy |
| 42 in cotton, vertical seams |
3 × 116 in |
9¾ yd |
| 42 in cotton, horizontal seams |
3 × 98 in |
8¼ yd |
| 108 in wide backing |
1 × 116 in |
3¼ yd |
Step 3: Consider wide backing
Wide backing fabric, usually 108 inches wide, covers a 98-inch backing in a single piece. You only need the length: 116 inches, or 3¼ yards, and there are no seams to sew or press.
Wide backing costs more per yard, but you buy far fewer yards. Multiply each option's yardage by its price per yard to see which is cheaper for your fabric choices.
Queen quilts come in different sizes
"Queen" isn't a fixed size. Patterns range from about 84 × 92 inches to 96 × 108 inches depending on how much drop over the sides the designer wants. Always measure your finished top, then run your own numbers in the quilt backing calculator, which compares both seam directions automatically.
Sewing the panels
- Trim the selvages before sewing. They're woven more tightly and can pucker.
- Use a ½-inch seam allowance for strength.
- Press seams open so the backing lies flat and there's less bulk for the longarm or your machine to cross.
- Square the backing, then mark the centre of each side to help line it up with the top.
If you're sending your quilt to a longarm quilter, ask whether they prefer seams in a particular direction before you sew. Some prefer seams that run parallel to the machine's rollers.
Other queen sizes
Queen patterns vary. With 4 inches of overhang on each side:
| Queen top |
Backing size |
42 in cotton |
108 in wide |
| 84 × 92 in |
92 × 100 in |
7¾ yd (horizontal seams) |
2⅞ yd |
| 90 × 108 in |
98 × 116 in |
8¼ yd (horizontal seams) |
3¼ yd |
| 96 × 108 in |
104 × 116 in |
8¾ yd (horizontal seams) |
3¼ yd |
In every case, horizontal seams use less cotton than vertical ones for these sizes.
Cutting the panels
For the 90 × 108 inch example with horizontal seams:
- Cut three panels, each 98 inches long, from 8¼ yards.
- Trim the selvages.
- Sew the panels together along their long edges with ½ inch seams.
- Press the seams open.
- The backing now measures about 98 inches wide and about 118 inches long before trimming, enough for the 116 inch length you need.
Using up fabric from your stash
You don't need one fabric. A backing can be pieced from two or three coordinating prints, or include a strip of leftover blocks. Just make sure the finished backing is at least 98 × 116 inches and that seams are pressed flat.
Common mistakes
Measuring the pattern, not the finished top. Piecing and quilting shrink a top slightly. Measure what you've actually made.
Cutting all panels the quilt's length. Check whether horizontal seams would save fabric first.
Leaving selvages on. They're tighter woven and can pucker after washing.
Too little overhang for a longarm. Ask your quilter; some need more than 4 inches per side.