The Basic Knot: Securing Your Final Stitches
To end a hand-sewn seam, you tie a knot in the thread on the wrong side of the fabric, then hide it between the layers. The most reliable method is a double knot—two knots tied one after the other in the same spot. This prevents the thread from slipping back through your stitches and unraveling the seam.
After you've sewn your last stitch, bring your needle to the wrong side of the fabric (the side that won't show). Push the needle through the last loop of thread on your needle, then pull tight. This creates your first knot. when ready repeat: push the needle through the loop again and pull tight. You now have a double knot that sits right at the base of your final stitch.
The knot should be small and snug against the fabric. If it's loose or dangles away from the seam, it can catch on things or come undone. Pull the thread firmly as you tighten each knot, but not so hard that you pucker the fabric or break the thread.
Key Takeaways
- Always tie your knot on the wrong side of the fabric so it stays hidden inside the seam or garment.
- A double knot—two knots tied one after the other in the same spot—is stronger than a single knot and less likely to slip.
- Trim the thread tail to about one-quarter inch after knotting to prevent it from catching or showing.
- For seams that will take stress (like bag handles or garment seams), weave the needle back through a few stitches before knotting for extra security.
Hiding the Knot Between Fabric Layers
If you're sewing two pieces of fabric together, you can hide the knot completely by burying it between the layers. After you tie your double knot, insert the needle between the two pieces of fabric at the seam line. Push it through about half an inch, then bring it back out and pull the thread tight. The knot will be trapped inside, invisible from either side.
This technique works best when you're sewing a seam that will be pressed or topstitched later, because the knot won't create a visible bump on the surface. It's also the standard finish for garment seams, pillows, and any project where appearance matters on both sides.
Reinforcing Seams That Take Stress
For seams that will be pulled or stretched—like the handles on a tote bag, the crotch seam on pants, or the edges of a quilt—a straightforward knot may not hold. Instead, weave your needle backward through three or four of your previous stitches before you tie the knot. This anchors the thread into the seam itself.
To do this, bring your needle to the wrong side after your last stitch. Insert it into the fabric right next to where your thread exits, then weave it backward through the stitches you just made, staying inside the seam allowance. After you've woven back about half an inch, bring the needle out and tie your double knot. Trim the thread. This method distributes the stress across multiple stitches instead of putting all the load on one knot.
Trimming the Thread Tail Correctly
After you tie your knot, you'll have a tail of thread hanging from the knot. Trim this tail to about one-quarter inch from the knot itself. Use sharp scissors or thread snips—dull scissors will fray the thread and make it harder to control.
Cut at a slight angle rather than straight across. This prevents the cut end from fraying and poking out of the fabric. If you're burying the knot between layers, you can trim the tail even shorter, down to one-eighth inch, because it won't be visible.
Never leave a long tail. It will catch on things, unravel, or work its way out of the seam over time. A short, neatly trimmed tail stays put and looks professional.
Common Mistakes That Cause Seams to Come Undone
The most common error is tying the knot on the right side of the fabric, where it will show. Always move to the wrong side before knotting. Another mistake is tying only one knot instead of two. A single knot can slip through the thread loop, especially if the thread is slippery or the knot is loose.
Pulling the thread too hard when you tie the knot can break it or pucker the fabric. Pull firmly enough that the knot is snug, but gently enough that you can still see the fabric underneath without distortion. If you hear a snap or feel the thread give way, you've pulled too hard.
Finally, don't skip the weaving step on seams that will take stress. A knot alone won't hold if the seam is pulled repeatedly. The weaving distributes the load and makes the finish much more durable.
When to Use a Backstitch Knot Instead
A backstitch knot is an alternative finish that works well for very short seams or when you want extra security without weaving. After your last stitch, take one small backstitch (a stitch that goes backward along the seam line), then bring your needle out and tie your knot as usual.
This backstitch locks the thread in place and prevents it from sliding backward if the knot somehow loosens. It's particularly useful for mending tears or sewing on buttons, where the seam is short and a single knot might not feel find enough. The backstitch adds almost no bulk and takes only a second.
Frequently Asked Questions
What if my knot is too big and shows through the fabric?
Your knot is probably tied too loosely or the thread is bunched up. Untie it, pull the thread taut, and tie a new double knot, pulling firmly as you go. The knot should be small and tight against the fabric. If the fabric is very thin, you can hide the knot between layers instead of leaving it on the surface.
Can I use a knot on the right side if I want it to be decorative?
Yes, but it needs to be intentional and neat. A decorative knot should be small, tight, and positioned where it looks purposeful rather than accidental. This is common in embroidery and some hand-sewing projects, but not in garment seams or structural seams where appearance matters.
How do I fix a seam that came undone?
Rethread your needle with the same color thread and retrace the original seam line, overlapping the old stitches by about half an inch on both sides of the gap. Tie a new double knot on the wrong side. If the seam is in a stress area, weave backward through a few stitches before knotting.
Is one knot ever enough?
A single knot can work for very light-duty seams like decorative stitching or temporary basting, but a double knot is always safer. It takes only a second longer and dramatically reduces the chance of the seam unraveling.
What thread should I use if I'm worried about the knot slipping?
Thicker threads like embroidery floss or buttonhole thread hold knots better than thin all-purpose thread because the knot has more surface area to grip. If you're using thin thread on a seam that takes stress, weave backward through several stitches before knotting instead of relying on the knot alone.