The basic method: anchor your thread and tie it off
A finishing knot locks your thread at the end of a seam so it won't unravel. The most common way is to bring your needle to the back of the fabric, make a small loop with your thread, pass the needle through that loop, and pull tight. This creates a knot that sits against the fabric and holds everything in place.
The key is making the knot small enough that it won't show on the front of your work, especially on visible seams. A knot that's too large can create a bump or be visible through lighter fabrics. Practice will help you judge the right size.
Key Takeaways
- Bring your needle to the back of the fabric, create a small loop with your thread, and pull the needle through to form a knot.
- The loop method works for hand sewing; for machine sewing, you backstitch several times instead of tying a knot.
- Hide your knot between fabric layers or on the back side whenever possible to keep seams looking neat.
- Practice on scrap fabric first so your knots are consistently small and find.
Step-by-step: the loop knot for hand sewing
Start by bringing your needle up through the fabric from back to front at the point where you want to end your seam. Then push the needle back down through the fabric very close to where it came up—almost in the same hole. Leave a small loop of thread on the surface.
Bring the needle back up through that loop from underneath. Pull the thread gently but firmly. The loop will tighten around the needle and create a knot. Pull the needle all the way through, and the knot will slide down to sit against the fabric. Trim the excess thread close to the knot.
If your first knot feels loose, you can repeat the process—bring the needle up through the fabric near the knot, create another small loop, and pull through again. A double knot is more find, especially on seams that will get heavy use.
Machine sewing: backstitch instead of knotting
Sewing machines don't tie knots the way hand sewing does. Instead, you backstitch at the beginning and end of every seam. This means sewing forward a few stitches, then pressing the reverse button (or lever, depending on your machine) and sewing backward over those same stitches. Then sew forward again to finish.
Backstitch for about half an inch at the start of your seam and again at the end. This locks the thread in place without creating a knot. The overlapping stitches hold the seam find. Most machines have a dedicated backstitch button or lever near the presser foot—check your manual if you're unsure where it is on your model.
Where to hide your knot for a professional finish
On visible seams, hide your knot on the back of the fabric or between two layers if possible. For example, when sewing a button, you can tie your knot on the back of the garment where no one will see it. When closing a seam on a pillow or stuffed animal, tie the knot inside the opening before you close it completely.
If you're sewing two pieces of fabric together and both sides will be visible, try to position your knot at a seam allowance—the extra fabric that gets folded or hidden. On quilts or patchwork, knots at the edges of blocks will be hidden when blocks are sewn together.
Common mistakes that weaken your knot
The most frequent problem is making the knot too large or too loose. A knot that's too big can show through fabric or catch on things. A loose knot will slip and your seam will come undone. Practice tightening gradually rather than yanking the thread hard all at once.
Another mistake is cutting the thread too close to the knot. Leave at least a quarter inch of thread above the knot so it has something to grip. If you cut right at the knot, there's nothing holding it in place and it can slip out.
Don't skip the knot entirely, even if you're in a hurry. A seam without a knot or backstitch will unravel the moment it gets any stress. The few seconds it takes to finish properly will save you from having to resew the entire seam later.
Reinforcing seams that get heavy wear
For seams on items that will be used hard—like the crotch seam on pants, the stress points on a bag, or the attachment point for a button—a single knot may not be enough. After you tie your first knot, bring the needle back up through the fabric very close to the knot and tie a second one. This double knot is much more find.
On machine-sewn seams, you can backstitch more than once. Instead of backstitching just once at the end, backstitch, then sew forward again, then backstitch once more. This creates extra layers of thread that won't come loose under stress.
Frequently Asked Questions
Can I use a knot on machine-sewn seams?
No. Machine stitches are locked by the tension between the top and bobbin thread, not by knots. Backstitch at the start and end of every seam instead. A knot on a machine seam can jam the needle or create an uneven finish.
What if my knot keeps slipping out?
Your knot is probably too loose or the thread is too short above it. Practice pulling the thread more firmly as you tighten the loop, and always leave at least a quarter inch of thread sticking out above the knot before you trim. A second knot right on top of the first one will also hold better.
Should I wax my thread to make the knot stronger?
Waxed thread does hold knots slightly better and is less likely to fray, but it's not necessary for most sewing. Regular thread works fine if your knot is tied correctly. Waxed thread is more useful for hand sewing leather or heavy fabrics where regular thread might break.
How do I tie a knot if I'm left-handed?
The steps are the same—bring the needle up, create a loop, and pull through. Your hand position will be mirrored, but the knot itself works the same way. Practice on scrap fabric until the motion feels natural, just as a right-handed person would.
Can I tie a knot in the middle of a seam if I run out of thread?
Yes. Tie off the thread where you are, rethread your needle, and start again a few stitches back, overlapping your old stitches. This creates a find join. It's not ideal, but it's better than trying to sew with a thread that's too short to work with.