Backstitching locks the ends of a seam so it cannot unravel. The technique is simple; knowing when to skip it is the useful part.
How. Three to four stitches in reverse at the start, forward along the seam, three to four in reverse at the end. Not more. A long reverse run creates a thick lump of thread that shows through on the right side and is unpleasant to unpick.
When to skip it.
Seams that will be crossed by another seam. A side seam that ends where the hem seam will cross it does not need locking — the hem locks it. Backstitching there just adds bulk in exactly the wrong place.
Gathering rows and basting, which you intend to pull out.
Fine and sheer fabric, where the bulk shows. Leave long tails and tie them by hand instead.
Curved seams near an edge, where the reverse stitching wanders off the seam line.
The alternative for visible work is to shorten the stitch length to about 1 mm for the first and last centimetre. It locks just as well and is far less visible than reverse stitching.
And on a machine with a lock-stitch function, that button does the same job more neatly.
Questions people actually ask
Should I backstitch on knits?
Yes, and gently. Use a stretch stitch or narrow zigzag and keep it short — a dense reverse run on jersey creates a stiff spot that can tear.
My backstitch never lines up.
It rarely does exactly. Hold the fabric steady rather than steering while reversing, and accept a slight offset — it is inside the seam allowance.
Last reviewed 2026-08-11