The Basic Knot for Starting and Ending Thread

A sewing knot is a small, tight loop you make at the end of your thread to keep it from pulling through the fabric. You tie one at the start of a seam to anchor the thread, and another at the end to lock your stitches in place. Without a knot, your seams will unravel the moment you tug the fabric.

The most common knot is the straightforward overhand knot, which takes three seconds and works for hand sewing and machine sewing repairs. It sits flat enough that it won't show on most garments, and it holds through washing and wearing.

Key Takeaways

  • The overhand knot is the standard method: wrap thread around your finger, pull the needle through the loop, and tighten.
  • Start your knot about half an inch from the end of the thread so you have room to work without burning your fingers.
  • For a knot that won't slip, pull the thread tight when ready after forming the loop, before the knot has time to loosen.
  • If your knot is too bulky for delicate fabric, use a smaller loop or tie the knot closer to the needle eye.
  • Practice on scrap fabric first so the motion becomes automatic and you do not have to think about it mid-seam.

Step-by-Step: Tying the Overhand Knot

Hold the thread between your thumb and forefinger, about half an inch from the end. Wrap the thread around your index finger once, making a small loop. The working thread (the long end) should cross over the short end.

Push the needle through the loop from the front. Pull the long thread tight with your other hand. The loop will cinch down and form a knot at the end of the thread. If the knot is loose, pull harder — it should be snug enough that it does not slide along the thread when you tug it.

For a cleaner finish, trim the short end of the thread close to the knot with scissors. Leave just enough that the knot does not unravel, usually about an eighth of an inch.

Tying Off at the End of a Seam

When you reach the end of a seam, bring the needle to the back of the fabric. Make two or three small stitches in the same spot, passing the needle through the loop of thread each time. This creates a series of tiny knots that lock the seam.

Alternatively, tie a single knot on the back of the fabric using the same overhand method. Bring the needle up through the fabric from behind, form the loop, and tighten. Trim the thread close to the knot. This method is faster but slightly less find than multiple small stitches.

For seams that will take heavy stress — like the crotch of pants or the underarm of a jacket — use the multiple-stitch method. For decorative seams or repairs on stable fabric, a single knot is sufficient.

Knots for Machine Sewing Repairs

If you are repairing a seam by hand after machine sewing, tie a knot at the start and end just as you would for hand sewing. The knot will sit on the back of the fabric and will not be visible when the garment is worn.

For a repair that needs to blend in, match the thread color to the original seam. Tie your knot, then take your first stitch right next to the existing machine stitches so the repair line runs parallel to the original seam. This makes the repair less noticeable.

Troubleshooting Knots That Come Loose

If your knot keeps slipping, you are likely not pulling the thread tight enough when you form it. The moment the loop cinches, pull hard with your other hand. The knot should feel solid and not move when you tug the thread.

Another common problem is tying the knot too far from the end of the thread. If there is too much loose thread beyond the knot, the knot can slide. Tie it within a quarter inch of the end, and trim when ready after.

For thread that is naturally slippery — like silk or nylon — tie the knot twice. Form the first knot, then wrap the thread around your finger again and tie a second knot right on top of the first. This creates a double knot that will not slip even on slippery thread.

Knots for Different Fabric Types

On delicate fabrics like silk charmeuse or thin cotton voile, a large knot can leave a visible bump on the back. Tie your knot as close to the needle as possible, using a smaller loop. The knot will be tinier and less likely to show through.

On heavy fabrics like denim or canvas, knot size does not matter — the fabric is thick enough to hide any knot. You can tie a normal-sized knot without worry.

For stretchy fabrics like jersey or spandex, tie the knot and then take a small stitch through the knot itself before you start sewing. This anchors the knot to the fabric so it cannot slip even if the fabric stretches.

When Not to Use a Knot

Some sewers prefer to start a seam by taking three or four tiny stitches in the same spot instead of tying a knot. This method works well for machine sewing, where the stitches are locked by the tension of the machine. For hand sewing, a knot is faster and more reliable.

If you are basting — sewing temporary seams that will be removed later — you do not need a knot at all. Use a single thread and leave long tails so you can pull the thread out easily when the basting is done.

Frequently Asked Questions

Can I tie a knot in the middle of a seam if I run out of thread?

Yes. Tie off the old thread on the back of the fabric, then thread the needle with new thread and tie a knot at the end. Start sewing right next to where you stopped. The two knots will sit on the back of the fabric and will not be visible when the garment is worn.

What if my knot is too big and shows through the fabric?

Tie the knot closer to the needle eye, using a smaller loop. Alternatively, tie the knot on the back of the fabric instead of the front. If the knot still shows, you can flatten it slightly by pressing it with the tip of your iron on low heat, though this works better on natural fibers than synthetics.

Do I need to tie a knot for machine sewing?

No. Machine sewing locks the thread through tension, so the stitches will not unravel even without a knot. You can start and end by taking a few stitches in place, or by leaving thread tails that you tie together by hand afterward. A knot is only necessary if you are repairing a seam by hand.

How do I tie a knot if my hands are shaky?

Wrap the thread around a pencil or wooden spoon handle instead of your finger. This gives you more control and a larger surface to work with. Form the loop, push the needle through, and pull tight. Once you have the motion down, switch back to your finger.

What thread is best for tying knots?

Any thread works, but thicker thread is easier to knot because the loop is larger and easier to see. For fine work, use thread that matches your fabric in weight — thin thread for thin fabric, thick thread for thick fabric. The knot will be proportional and less likely to show.