How do I stop my seams fraying without an overlocker?

Four finishes you can do on an ordinary machine or with shears, compared on bulk, durability and what fabric each suits — and how to tell which your fabric actually needs.

Difficulty: beginner
Time: 20 min
Read: 5 min

Short answer

Zigzag along or just over the raw edge with a medium width and short length — that covers most fabrics on any machine. Pinking shears are enough for tightly woven cloth that is rarely washed. A French seam encloses the edges entirely and is the most durable, for straight seams on light fabric. Choose by how badly the fabric frays, not by neatness.

Woven fabric frays because the cut edge releases the yarns running the other way. How much it frays depends on the weave: a tightly woven poplin sheds a millimetre and stops, while a loose linen or a rayon challis will unravel until the seam gives way. Finishing the edge is what stops that, and an overlocker is only one of several ways to do it.

What you'll need

A machine with a zigzag stitch, for most of these
Pinking shears
Sharp fabric scissors
An iron

Four ways to finish a raw seam edge compared

Step by step

Test how much your fabric frays before deciding.Cut a scrap, rub the raw edge hard between your fingers a dozen times and see what comes away. Almost nothing means pinking will do. A pile of loose threads means the edge needs binding or enclosing.
Zigzag for everyday sewing.Set a medium width — about 3mm — and a fairly short length, about 1.5mm. Run the stitch so the right swing just falls off the raw edge, which wraps the edge slightly. Do the two allowances separately if the seam is pressed open, or together if pressed to one side.
Deal with zigzag tunnelling on light fabric.A zigzag that pulls the edge into a tight roll needs a narrower, longer stitch and a lower tension, or a strip of tissue paper underneath torn away afterwards. A three-step zigzag, if the machine has one, tunnels far less.
Use pinking shears where the fabric barely frays.Cut the allowance with the zigzag shears so any fray runs only to the next notch. Fast, adds no bulk, needs no machine. Not adequate for loose weaves, for anything washed frequently, or for a garment expected to last years.
Use an overcast stitch and foot if your machine has one.Many machines include an overcasting stitch and a foot with a small bar that the thread wraps around, which stops the edge curling. It is the closest a domestic machine gets to an overlocked edge and it is worth learning if you have it.
Bind the edge for an unlined jacket or a visible seam.Bias binding folded over the raw edge and stitched through. It is the smartest-looking finish, it is what makes an unlined garment look expensive inside, and it adds noticeable bulk and time.
Enclose the edge with a French seam on light straight seams.Sewn twice so the raw edges are sealed inside a channel. The most durable finish of all and the right answer for sheer and light fabric where any edge would show through.
Use a flat-felled seam on shirts and workwear.One allowance trimmed, the other folded over it and topstitched down. Strong, flat, fully enclosed, and it is the seam on the outside of a pair of jeans and up a shirt sleeve. It needs straight seams and shows two rows of topstitching on the right side.
Finish before you assemble where it makes sense.On a garment with long straight seams it is often quicker to finish each piece's edges before sewing the seams than to wrestle a part-made garment under the foot.

Tips

Knits do not fray — the edge rolls but it does not unravel — so a knit seam needs no finish at all unless you want it neater.
If a fabric frays so badly that it sheds while you are cutting, spray the cut edges lightly with starch or use a fray-stopping liquid on the very worst areas before you handle them.
Pressing the allowances before finishing makes every method easier and neater.
Choose the finish before you cut, because French and flat-felled seams use the allowance differently and you may need a wider one.

Common mistakes

Zigzagging with too wide and too short a stitch on fine fabric — It packs so much thread into the edge that the fabric tunnels into a hard rolled cord, which then shows as a ridge through the right side.
Pinking a loosely woven fabric — Pinking only shortens the path a fray can travel. In a loose weave the yarns pull out along the notch edges anyway and the seam is no better protected than raw.
Choosing a French seam for a curved or thick seam — The second row of stitching has to enclose the first, and on a curve or in thick cloth the allowance will not turn cleanly, so the raw edges escape.

Alternatives

Zigzag: Any machine with a zigzag. Suits nearly all woven fabric, adds very little bulk, quick. Can tunnel on very light cloth unless the stitch is adjusted.
Pinked edge: Zigzag shears only, no machine. Fastest and flattest. Only adequate on tightly woven fabric in a garment that is not washed hard.
Bias bound: Bias binding wrapped over the edge and stitched. The neatest visible finish, ideal inside an unlined jacket. Slow and adds bulk.
French seam: Sewn twice with the raw edges sealed inside. The most durable, and the right choice for sheers and light fabric. Straight or gently curved seams only.
Flat-felled seam: One allowance folded over the other and topstitched. Very strong and completely enclosed, as on jeans and shirts. Shows two rows of stitching on the right side.
Overlocker: Trims and wraps in one pass, which is what factory garments have. Neatest and fastest, and it is a separate machine to buy, thread and maintain.

Questions people ask

Do I have to finish seams at all?

On a garment that will be washed, yes, on any woven fabric that frays. On a cushion cover, a lined bag or anything where the seam is enclosed and never washed, a pinked or even raw edge is often fine.

Should I finish the allowances together or separately?

Separately if the seam is pressed open, together if it is pressed to one side. Finishing together is quicker and slightly bulkier, and it is what most ready-to-wear does.

Is a zigzag as good as an overlock?

Close enough for almost all home sewing. An overlocker is faster, neater and trims as it goes, but a well-set zigzag on the edge holds a fray back just as effectively.