Backstitch is the lock that keeps your seams from unraveling

A backstitch is a few stitches sewn in reverse at the start and end of a seam. It locks the thread so the seam does not come apart when you wash or wear the garment. Most sewing machines have a reverse button or lever that lets you stitch backward for a second or two, then forward again. Without a backstitch, even a perfectly straight seam will fray and fail.

You do not need special thread, special fabric, or a particular machine model. Any machine with a reverse function can backstitch. The whole process takes about three seconds per seam end.

Key Takeaways

  • Press the reverse button or lever on your machine while it is running to stitch backward; release it to return to forward stitching.
  • Backstitch at the start of a seam by sewing forward two or three stitches, then reversing for two or three stitches, then continuing forward.
  • Backstitch at the end of a seam by reversing for two or three stitches just before you reach the edge of the fabric.
  • The reverse function is usually a button on the front of the machine or a lever near the presser foot; check your manual if you cannot locate it.

Where to find the reverse button on your machine

The reverse control varies by machine type. On most modern machines, it is a button on the front panel labeled with an arrow pointing left or a small "R" for reverse. Press it while the machine is running and the needle will move backward. Release it and the needle returns to forward motion. Some older or mechanical machines have a lever near the presser foot that you push down or to the side to engage reverse.

If you cannot find the reverse control, check the manual that came with your machine or search the manufacturer's website for your model number. The manual will show you exactly where it is and how to use it. Do not assume the machine does not have reverse—nearly all machines made in the last 30 years have this feature.

Backstitch at the beginning of a seam

Start by positioning your fabric under the presser foot and lowering the foot to hold it in place. Lower the needle into the fabric by turning the handwheel or pressing the needle-down button. Now sew forward for two or three stitches at normal speed. Then press and hold the reverse button while the machine continues to run. The needle will move backward over those same two or three stitches. After two or three backward stitches, release the reverse button and continue sewing forward along your seam line.

The result is a small cluster of stitches going forward, then backward, then forward again. This tangle of thread is what locks the seam. You do not need to stop the machine or lift the presser foot—just press the button and keep going.

Backstitch at the end of a seam

When you reach the end of your seam, about a quarter inch before the fabric edge, press the reverse button. Sew backward for two or three stitches, just as you did at the start. Then release the reverse button, lift the presser foot, and remove the fabric. The seam is now locked at both ends.

If you sew all the way to the edge of the fabric and then backstitch, the thread may pull the fabric or create a pucker. Backstitch slightly before the edge to avoid this. With practice, you will develop a feel for the right distance.

Common mistakes and how to avoid them

The most common error is forgetting to backstitch at all. If you start sewing and go straight forward without reversing, the first few stitches will have no lock. When you wash the garment, those stitches come loose and the seam begins to fray. Make backstitching a habit: forward, reverse, forward at the start; reverse before the end.

Another mistake is backstitching too many times. Two or three stitches in reverse is enough. Backstitching five or six times does not make the seam stronger—it just wastes thread and can create a stiff, bulky spot. Keep it short and straightforward.

Some sewers accidentally press the reverse button while sewing the main seam, which creates a wobbly line. Make sure you know where the reverse button is before you start, so you do not hit it by accident. If your machine has the reverse lever near the presser foot, keep your fingers clear of it while sewing forward.

Backstitch on different fabric types

Backstitch works the same way on all fabrics—cotton, polyester, knit, linen, and others. The only difference is thread tension and stitch length, which you adjust before you start sewing, not during the backstitch. A backstitch on heavy fabric like denim uses the same reverse motion as a backstitch on light fabric like cotton voile.

On stretchy fabrics like jersey or spandex, some sewers use a ballpoint needle and a slightly longer stitch length to prevent runs. The backstitch itself does not change. You still sew forward two or three stitches, reverse two or three stitches, and continue forward. The lock works the same way.

When you cannot backstitch

A few situations prevent backstitching. If your machine has no reverse function, you can tie off the thread by hand instead. Pull both thread ends to the back of the fabric, tie them in a knot close to the seam, and trim the excess. This is slower than backstitching but it works.

If you are using a serger or overlock machine, backstitching does not explore because the machine uses a different stitch structure. Sergers lock thread automatically as they cut and bind the fabric edge. Check your serger manual for how to find the seam on that machine.

Frequently Asked Questions

Do I have to backstitch on every seam?

Yes, on seams that will be worn or washed. Backstitching prevents the seam from unraveling. On temporary seams like basting stitches that you will remove later, you can skip it. On any seam that stays in the finished garment, backstitch both ends.

What if I backstitch too far and go past the fabric edge?

The thread will hang loose at the edge. Trim it close to the fabric with scissors. The seam is still locked because the stitches are in the fabric; the loose thread at the edge does not affect the hold. This happens to most sewers at some point and is not a problem.

Can I backstitch by hand if my machine is broken?

Yes. Thread a needle, tie a knot at the end, and push the needle through the fabric from back to front at the start of the seam. Then push it back through the same hole and forward again, creating a short stitch. Repeat this two or three times. It is slower than a machine backstitch but it locks the seam the same way.

Does backstitch use more thread?

Yes, a small amount. A two-stitch backstitch at each end uses maybe an extra inch of thread per seam. Over a whole garment, the difference is negligible. The thread you save by not having to repair a failed seam far outweighs the small amount used in backstitching.

What stitch length should I use for backstitch?

Use the same stitch length you are using for the main seam. If your seam is set to a length of 2.5 millimeters, your backstitch will also be 2.5 millimeters. You do not change the stitch length dial when you backstitch—only the direction changes.