How Much Fabric for a California King Quilt Backing?
For a 102 x 99 inch california king quilt with 4 inches extra per side, buy 9 yards of 42 inch quilting cotton (3 panels, vertical seams) or 6 1/8 yards of 108 inch wide backing. If your longarmer asks for 6 inches per side, plan 9 1/4 or 6 3/8 yards.
This page works out backing for a california king quilt top of 102 x 99 inches, the typical size in our quilt size chart. If your top is a different size, the quilt backing calculator runs the same math for any measurement.
How much california king backing do you need for each overage?
Overage is the extra backing added to every side. Home quilters often use 2 to 4 inches, while longarm quilters typically want 4 to 6 inches so the frame can clamp the fabric.
| Extra per side | Backing size (in) | 42 in, vertical | 42 in, horizontal | 108 in wide |
|---|---|---|---|---|
| 2 in | 106 x 103 | 8 5/8 yd (3) | 8 7/8 yd (3) | 2 7/8 yd |
| 4 in | 110 x 107 | 9 yd (3) | 9 1/4 yd (3) | 6 1/8 yd |
| 6 in | 114 x 111 | 9 1/4 yd (3) | 9 1/2 yd (3) | 6 3/8 yd |
| 8 in | 118 x 115 | 9 5/8 yd (3) | 9 7/8 yd (3) | 6 5/8 yd |
How do you piece a backing for a california king quilt?
With 4 inches per side, the cheapest layout for standard cotton is vertical seams. Here is the cutting plan.
- Buy 9 yards of 42 to 45 inch quilting cotton, in one continuous length if possible.
- Cut 3 panels, each 107 inches long.
- Trim the selvages from both long edges of every panel.
- Sew the panels together along the long edges with a 1/2 inch seam and press the seams open. The finished piece needs to be at least 110 inches across, so the last panel only needs to be about 30 inches wide and you can trim the extra.
- Square the backing to about 110 x 107 inches and mark the center of each edge.
Seams and longarms
Many longarm quilters prefer backing seams that run horizontally, parallel to the frame rollers, because the fabric rolls more evenly. If yardage is close, ask which way your quilter wants the seams.
Does fabric width change the california king backing yardage?
Quilting cotton is sold as 42 to 45 inches wide, but the usable width after trimming selvages, and after prewashing, can be 38 to 44 inches. For some sizes that difference adds a whole panel.
| Usable width | Best layout | Yards |
|---|---|---|
| 38 in | 3 panels, vertical seams | 9 yd |
| 40 in | 3 panels, vertical seams | 9 yd |
| 42 in | 3 panels, vertical seams | 9 yd |
| 44 in | 3 panels, vertical seams | 9 yd |
What if your california king quilt is bedspread size?
A bedspread-style california king quilt that reaches toward the floor (a 22 inch drop plus a 12 inch pillow tuck) finishes near 116 x 118 inches. Its backing needs 13 7/8 yards of 42 inch cotton (4 panels) or 7 yards of 108 inch wide backing with 1 seam.
Longarms and frames for king-size quilts
King quilts are heavy. A midarm, sit-down longarm or frame system lets the machine do the work instead of your shoulders.
Grace Little Rebel Sewing and Quilting Machine
$2,799.00A midarm with built-in stitch regulation that can sit on a table or a frame.
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Handi Quilter Amara ST 20 Stationary Longarm with Lift Table
$9,495.00A 20 inch sit-down longarm with a lift table: room for king quilts without a frame.
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Grace Qnique 16X Longarm with Q-Zone Queen Frame
$4,849.00A complete longarm and frame system for quilting large tops edge to edge.
Check pricePrices change often, so confirm on Amazon. As an Amazon Associate we earn from qualifying purchases.
Is it cheaper to send a california king quilt to a longarmer or quilt it yourself?
Longarm services usually price by the square inch of the top. A california king top is 10,098 square inches, so even a modest edge-to-edge rate adds up across several quilts a year. Run your own numbers in the longarm cost calculator before deciding whether a sit-down longarm or frame belongs in your sewing room.
Frequently asked questions
How many yards of fabric do I need for a california king quilt back?
A california king quilt of 102 x 99 inches needs a 110 x 107 inch backing with 4 inches extra per side. In standard 42 inch cotton with about 40 inches usable, that is 9 yards cut into 3 panels. In 108 inch wide backing it is 6 1/8 yards. Buy an extra 1/4 yard if you plan to prewash or match a large print.
Should I use wide backing for a california king quilt?
Yes, for most quilters. Pieced from 42 inch cotton, a california king back needs 3 panels and 2 long seams. A single 6 1/8 yard length of 108 inch wide backing has no seams, which longarmers prefer, and is often cheaper per square inch.
How much extra backing does a longarm quilter need for a california king quilt?
Most longarm services ask for 4 to 6 inches extra on every side, and a few ask for 8. At 6 inches per side, the california king backing grows to 114 x 111 inches, which is 9 1/4 yards of 42 inch cotton or 6 3/8 yards of wide backing. Ask before you cut, because a short backing is the most common reason a quilt is sent back.
How do I cut and sew a pieced california king quilt backing?
Cut 3 panels of 42 inch cotton, each 107 inches long. Trim off the selvages, since they shrink differently. Sew the panels along their long edges with a 1/2 inch seam, press the seams open, then trim the pieced back to about 110 x 107 inches. Mark the center of each side to help line it up with the top.
Does washing fabric change how much backing I need?
Yes. Prewashed quilting cotton can lose 1 to 2 inches of width and several inches of length per yard, and trimmed selvages take another inch. If you prewash, plan with 38 to 40 inches of usable width. The usable width table on this page shows how the yardage changes, and a small change can add a whole panel on bigger quilts.
How we research: we compare manufacturer specifications, owner manuals, published standards and recurring themes in verified owner reviews. We do not test products in person, and this is researched guidance, not professional advice. Follow your machine manual and pattern, and take care with rotary cutters, hot irons and needles. As an Amazon Associate we earn from qualifying purchases.