The basic method: backstitch and cut

To end a stitch on a sewing machine, sew forward to the end of your seam, then press the reverse button (or lever, depending on your machine) and sew backward over the last half-inch of stitching. This backward stitching, called a backstitch, locks the thread in place so it will not unravel. Then raise the presser foot, pull the fabric away from the needle, and trim the thread tails with scissors or thread cutters.

The backstitch works because it tangles the thread loops together. When you sew forward, the top thread and bobbin thread interlock. When you backstitch, you cross over those same loops in reverse, creating knots that hold even under stress. Most machines have a dedicated reverse button on the front panel or a lever near the presser foot — check your manual if you are unsure which one yours has.

The length of the backstitch matters. A half-inch is standard and strong enough for most seams. If you backstitch too far (more than an inch), you waste thread and create a bulky knot. If you backstitch too little (a quarter-inch or less), the seam may still come loose over time.

Key Takeaways

  • Press the reverse button and sew backward over the last half-inch of your seam to lock the stitches in place.
  • Raise the presser foot before pulling the fabric away, or you risk bending the needle or breaking thread.
  • Trim thread tails close to the fabric with scissors or a thread cutter to prevent snagging.
  • If your machine has a thread cutter built into the presser foot, use it to cut both threads at once instead of reaching for scissors.
  • Backstitching at the start of a seam (before you sew forward) prevents the beginning from coming loose just as much as backstitching at the end.

Why backstitching matters more than you think

A seam that is not locked will eventually fray and separate, especially on garments that get washed and worn often. The stress of movement and laundering pulls the thread loops apart if there is nothing holding them together at the edges. A backstitch creates a physical knot that resists that pull.

Some sewers skip the backstitch on seams that will be crossed by another seam later — for example, the side seam of a shirt that will be crossed by the armhole seam. The logic is that the crossing seam will hold it in place. This works, but only if the crossing seam is actually sewn before the garment is washed. If you wash the garment before that second seam is done, the first seam will come loose. Backstitching at every end is the safer habit.

Step-by-step: the complete process

Start by sewing your seam in the normal forward direction. Watch the fabric move under the presser foot and listen for the rhythm of the needle — most machines make a steady clicking sound. When you reach the end of the line you want to sew, stop with the needle in the fabric (not raised).

Press and hold the reverse button or pull the reverse lever toward you. The needle will continue to move up and down, but the fabric will feed backward instead of forward. Sew backward slowly — you do not need to go fast — for about half an inch. Then release the reverse button and the machine will return to forward mode.

Raise the presser foot lever (usually on the right side of the machine, behind the needle). This releases the tension on the fabric. Pull the fabric straight back and away from the needle — do not pull to the side, as that can bend the needle. The thread should come free easily.

Use scissors or a thread cutter to trim the thread tails. Cut as close to the fabric as you can without cutting the fabric itself. If your machine has a thread cutter built into the presser foot or the back of the machine, use that instead — it cuts both the top thread and the bobbin thread at once, which is faster and neater.

What to do if you forget to backstitch

If you realize after removing the fabric that you forgot to backstitch, you can fix it by hand. Thread a needle with thread that matches your seam, tie a knot at the end, and push the needle through the loop of thread at the end of your seam. Pull the needle back through the same loop several times to create a knot. This is not as strong as a machine backstitch, but it will hold for light use.

For a seam that will get heavy wear — a crotch seam, a bag handle, a stress point — it is worth unpicking the last inch or so with a seam ripper and re-sewing it with a proper backstitch. The time it takes now is less than the time it takes to repair a failed seam later.

Machines with automatic thread cutters

Some modern machines have a thread cutter button on the front panel. When you press it after backstitching, the machine cuts both threads automatically and retracts the presser foot. This is convenient, but you still need to pull the fabric away by hand — the machine does not do that part.

Other machines have a thread cutter built into the presser foot itself. You raise the presser foot as normal, and as you pull the fabric away, the threads pass through a small cutting slot on the foot. This cuts them cleanly without you having to reach for scissors. Check your manual to see if your machine has either of these features.

Common mistakes that weaken seams

Pulling the fabric before raising the presser foot is the most common mistake. The presser foot holds the fabric in place against the feed dogs (the metal teeth that move the fabric). If you pull before raising the foot, you risk bending the needle, breaking the thread, or pulling the fabric out of alignment. Always raise the foot first.

Backstitching too far — more than an inch — creates a thick knot of thread that can be hard to press flat and may show through thin fabrics. It also wastes thread. A half-inch is enough.

Leaving long thread tails can cause them to catch on other parts of the garment or snag during washing. Trim them as short as you can. If the tail is so short that you cannot grip it with scissors, use a thread cutter or let it be — a very short tail is unlikely to cause problems.

Finishing seams on stretchy or delicate fabrics

On stretchy fabrics like knit or spandex, a single backstitch may not be enough because the fabric itself can stretch and pull the thread loose. Consider using a stretch stitch instead of a regular stitch if your machine has one — these stitches are designed to move with the fabric. If you use a regular stitch, backstitch twice: once at the normal half-inch, then again at the quarter-inch mark, to create a double lock.

On delicate fabrics like silk or lace, a long backstitch can pucker the fabric because the extra thread pulls the fibers together. Use a shorter backstitch — a quarter-inch instead of a half-inch — and sew more slowly so you have better control.

Frequently Asked Questions

Can I backstitch by hand instead of using the machine's reverse button?

No. Hand backstitching after the seam is done will not hold as well because the stitches will not interlock with the machine stitches the way a machine backstitch does. If you forget to backstitch on the machine, you can hand-stitch a knot at the end as a temporary fix, but re-sewing the end with the machine is better for seams that will get wear.

What if my machine does not have a reverse button?

Most machines made in the last 30 years have a reverse button or lever. Check your manual or the front and sides of the machine near the needle area. If your machine truly has no reverse function, you can tie off the thread by hand at the end of each seam, or look into whether your machine model has an optional reverse foot attachment.

Do I need to backstitch on both ends of the seam?

Yes. Both the beginning and the end of a seam need to be locked. Backstitch at the start of the seam before you sew forward, and backstitch again at the end. This takes only a few extra seconds and prevents the seam from coming loose from either direction.

Why does my backstitch look different from my forward stitches?

It should look the same. If the backstitch stitches are loose, uneven, or a different length, the tension may be wrong or the thread may not be threaded correctly. Check that both the top thread and bobbin are inserted properly and that the presser foot is down (tension only works when the foot is down). If the problem continues, consult your manual or a sewing machine technician.

Can I cut the thread while the needle is still in the fabric?

No. Always raise the presser foot and pull the fabric away first. Cutting the thread while the needle is down can cause the thread to jam in the machine or break inside, which may require a service call to clear.