The basic knot: what you need and how to make it

A sewing knot is a small loop you tie at the end of your thread to stop it from pulling through the fabric. The most common knot takes three steps: pinch the thread between your thumb and forefinger about half an inch from the end, wrap the thread around your finger once, roll it off with your thumb to create a small loop, then pull the long thread tight. The knot forms at the end and sits flat against the fabric.

You need this knot at the start of every seam and at the end. Without it, your stitches unravel the moment you stop sewing. The knot should be small enough that it pulls through to the back of the fabric without leaving a visible bump on the front, but large enough that it catches and holds.

Practice the motion a few times with scrap thread before you start a real project. Your fingers will learn the rhythm quickly — most people tie a knot without thinking about it after the first dozen tries.

Key Takeaways

  • A sewing knot prevents thread from unraveling by anchoring it at the start and end of each seam.
  • The standard method involves wrapping thread around your finger, rolling it off with your thumb, and pulling tight to form a small loop at the thread's end.
  • The knot should be small enough to pull through to the back of the fabric without creating a visible lump on the front.
  • You tie a knot twice per seam: once before you start stitching and once after you finish.

Step-by-step: the finger-wrap method

Hold the thread between your thumb and forefinger of your non-dominant hand, about half an inch from the very end. The short tail should point away from you. With your other hand, wrap the long thread around your forefinger once, going over the top and under the bottom so the thread crosses itself.

Now use your thumb to roll the wrapped thread off your finger toward your forefinger. As you roll, the thread twists and forms a small loop. Keep rolling until the loop slides off your finger completely. Pull the long thread tight — the loop tightens into a knot at the end of the short tail.

If the knot is too large or too loose, the thread will slip through it when you pull. If it is too small, it may not catch the fabric. After a few tries, you will feel the right amount of tension.

When the knot is too big or too small

A knot that is too large will create a visible bump on the front of your fabric, especially on lightweight cotton or linen. If this happens, trim the short tail very close to the knot with scissors, then gently pull the knot through to the back of the fabric before you start stitching. The knot should sit on the underside where nobody sees it.

A knot that is too small or too loose will slip through the fabric when you pull the thread tight. This usually happens when you do not roll the thread firmly enough around your finger. Tighten your grip and roll more deliberately. If the knot still slips, tie a second knot on top of the first one — this is a common fix and takes only a second.

Tying off at the end of a seam

When you finish stitching, bring the needle to the back of the fabric and take one small stitch in place — push the needle through the fabric and back out in almost the same spot. This anchors the thread. Then tie a knot the same way you did at the start: pinch the thread, wrap it around your finger, roll it off, and pull tight.

Some sewers tie two small stitches in place before knotting, which creates extra security. This is especially useful on seams that will get a lot of stress, like the underarm seam of a garment or the corners of a bag. The extra stitch takes only a few seconds and makes the seam much less likely to come apart.

Trim the thread tail close to the knot with scissors. If any thread is still visible on the front, gently pull the knot through to the back before you trim.

Alternative: the loop knot for hand sewing

Some sewers prefer a slightly different method called the loop knot. Thread your needle, then hold the needle and thread in one hand. With your other hand, wrap the thread around the needle shaft twice, close to the eye. Slide the needle through the loops you just created, pulling gently until a knot forms at the end of the thread.

This method works well if you find the finger-wrap method awkward. It creates a knot that is usually very small and sits flat. The downside is that it takes a bit more practice to get the loops tight enough that they do not slip.

Knots on different fabric weights

On heavy fabrics like canvas, denim, or upholstery cloth, a standard knot works fine because the fabric is thick enough to hold it. On lightweight fabrics like silk, voile, or thin cotton, a knot can sometimes poke through to the front or create a visible lump. In these cases, tie the knot, trim the tail very short, and pull the knot through to the back before you start stitching.

On stretchy fabrics like jersey or knit, a single knot may slip under stress. Tie two knots instead, one on top of the other. The extra knot takes only a moment and prevents the thread from coming loose when the fabric moves.

Common mistakes and how to fix them

The most common mistake is tying the knot too far from the end of the thread. If you pinch the thread two or three inches from the end instead of half an inch, the knot will be too large and too loose. Always measure about half an inch — this creates a knot that is small and tight.

Another mistake is not rolling the thread firmly enough around your finger. If you wrap it loosely, the knot will slip when you pull. Press your thumb and forefinger together as you roll so the thread stays tight against your skin.

If you tie a knot and it when ready comes undone, you probably did not pull the long thread tight enough. Pull harder — the knot should feel solid and not move when you tug on the thread.

Frequently Asked Questions

Can I sew without tying a knot?

No. Without a knot, the thread will pull straight through the fabric and your stitches will unravel. You can sew a few stitches in place at the start and end instead of tying a knot, but a knot is faster and more reliable.

What if I tie a knot and it pulls through the fabric?

The knot is too small or the fabric is too loose-weave. Tie a second knot on top of the first, or use a slightly heavier fabric for practice. If the knot still pulls through, take a small stitch in place before you tie the knot — this anchors the thread and prevents it from slipping.

How do I tie a knot if I am left-handed?

Use the same method but reverse the hands. Pinch the thread with your right hand, wrap it around your left forefinger, and roll it off with your right thumb. The motion is identical — only the hand positions change.

Do I need to tie a knot if I am using a sewing machine?

No. Sewing machines lock the thread automatically by stitching in place at the start and end. You only tie knots when hand sewing. On a machine, backstitch for a few stitches instead.