Plus Size Clothing Patterns

Commercial patterns are drafted for a B cup and a standard proportion, so plus-size sewists often need to choose a size by high bust, grade between sizes and make a full bust adjustment. The tools below help with both, and draft a circle skirt pattern to your own measurements that prints at full size on home paper — no size chart needed.

Why plus-size patterns need adjusting

Most sewing patterns are drafted from a base size with a B cup and then graded up and down. Plus-size bodies vary far more than the grading assumes: bust, waist and hip differences, a fuller upper arm, a fuller tummy or a rounded upper back are all common. Some pattern companies draft separate plus-size blocks — often for a D cup or with extra room at the tummy — which makes a big difference. Check the pattern envelope or the designer’s size chart for the cup size and figure the pattern was drafted for.

Choosing a size: high bust, not full bust

1. Measure your high bust — around your back, under your arms and above the fullest part of your bust.
2. Add about 2 in (5 cm) to estimate what your full bust would be with a B cup.
3. Choose the pattern size whose bust matches that number. This fits your shoulders, neckline and upper chest.
4. If your full bust is larger than the pattern’s full bust, make a full bust adjustment.
5. Choose the waist and hip sizes separately and blend (grade) between them at the side seams.

Choosing by full bust instead usually gives gaping necklines and shoulders that are too wide, because the extra width goes everywhere rather than just over the bust.

The full bust adjustment (FBA)

A full bust adjustment adds width and length over the bust without enlarging the shoulders. You draw lines through the bust point on the front pattern piece, cut, and spread the pattern by half the extra bust amount (because the front piece is half the front). The result is a larger bust dart, or a new dart if the pattern had none. The calculator above gives the amount per side: if the pattern’s bust is 44 inches and your full bust is 47, each side needs 1.5 inches, adding 3 inches across the front. Knit patterns often need less — or no — FBA because the fabric stretches.

Ease: what the numbers on the envelope mean

Body measurements tell you which size to start with; finished garment measurements (often printed on the tissue or in the instructions) tell you how the garment will actually fit. Compare the finished measurements to your body plus the ease you like.

Circle skirts: the maths

Circle skirts suit any size because they are drafted from your own waist measurement, with no hip measurement at all. The drawback is fabric: a full circle at plus sizes often won’t fit across 60-inch fabric in one piece, so the tool tells you when to cut two half circles instead.

Worked example: circle skirt

For a 40-inch waist and a 24-inch finished length, a full circle skirt has a waist radius of 40 ÷ 6.283 = 6.37 inches. With a 1-inch hem allowance the outer radius is 31.4 inches, so the full circle is almost 63 inches across — too wide for 58–60-inch fabric. The tool suggests cutting two half circles joined at the sides, needing about 3.6 yards. A half circle skirt from the same waist needs a radius of 12.7 inches and less fabric, with less swing.

Printing the pattern

The pattern prints at full size across several pages with a 1-inch test square on the first. Print at 100% (“actual size”), measure the test square, then trim and tape pages together using the page labels (row letter, column number). For long skirts it is often quicker to draw the arcs directly on paper or fabric with a tape measure pivoting from the corner — the tool gives the radii for that method too.

Common plus-size fitting adjustments

• Full bust adjustment (FBA) — more room over the bust.
• Full tummy adjustment — more length and width at the front waist and hip.
• Full upper arm adjustment — widen the sleeve.
• Round back adjustment — more length across the upper back.
• Full seat adjustment — more room in trousers and fitted skirts at the back.
• Lengthen or shorten at the marked lines to suit your height.

The pattern pack

The optional pack includes a plus-size measurement worksheet, a pattern size comparison sheet, an FBA step-by-step guide, a fitting adjustments log and an Excel fabric yardage calculator. The tools on this page are free.

AI-assisted content

This page was drafted with AI assistance and reviewed by Kedop. Always make a toile (test garment) before cutting good fabric.