The Basic Method: Kitchener Stitch

The strongest and most invisible way to join two pieces of knitting is the Kitchener stitch, also called grafting. It works by threading yarn through live stitches on two needles and mimicking the path the yarn would take if you were knitting a row. The seam is nearly invisible because you are essentially knitting the two pieces together rather than sewing them.

To start, you need both pieces with live stitches still on needles—not cast off. If you have already cast off, you can pick the stitches back up with a needle, though this takes patience. Thread a blunt yarn needle with a length of yarn about three times the width of the seam you are closing. Hold the two needles parallel, with the working yarn coming from the right side of the back piece.

The stitch itself follows a repeating pattern: insert the needle through the first stitch on the front needle as if to purl, pull the yarn through, then insert through the same stitch as if to knit and slip it off. Move to the back needle and repeat—through the first stitch as if to knit, pull yarn through, then as if to purl and slip it off. Continue this pattern across until all stitches are joined. The rhythm becomes automatic after a few stitches.

Key Takeaways

  • Kitchener stitch creates an invisible seam by threading yarn through live stitches on two needles in a specific pattern that mimics knitting.
  • Both pieces must have live stitches on needles when you start; if cast off, you will need to pick stitches back up with a needle.
  • The stitch alternates between front and back needles, going through each stitch twice—once as if to purl, once as if to knit—before slipping it off.
  • Tension matters: keep the yarn loose enough to move freely but tight enough that the seam does not gap when you finish.
  • Three-needle bind-off creates a visible ridge and works best for seams you want to show, like shoulder seams on some garments.

Three-Needle Bind-Off for Visible Seams

If you want a seam that shows—or if you prefer a faster method—use the three-needle bind-off. This technique uses a third needle to bind off two pieces at once, creating a ridge on one side of the seam. It is common for shoulder seams and works well when the seam is meant to be part of the garment's design.

Hold the two needles with live stitches parallel in your left hand, with the right sides of the fabric facing each other (or wrong sides, depending on where you want the ridge). Pick up a third needle in your right hand. Knit through the first stitch on the front needle and the first stitch on the back needle at the same time, as if they were a single stitch. Repeat with the next pair of stitches. You now have two stitches on your right needle. Pass the first stitch over the second and off the needle, just as you would in a regular bind-off. Continue across until one stitch remains, then cut the yarn and pull it through.

The three-needle bind-off is faster than Kitchener stitch and does not require picking up dropped stitches later, but the seam will always be visible. Use it when you are joining pieces where a seam line is expected or desired.

Picking Up Dropped Stitches Before You Join

If you have already cast off both pieces and want to use Kitchener stitch, you will need to pick the stitches back up. This is tedious but not difficult. Look at the row just below the cast-off edge and identify each stitch—they form a chain of loops.

Insert a needle from front to back through the first loop, then the second, working across the entire width. You are threading the needle through the bumps of the stitches in that final row. Once all stitches are on the needle, you can proceed with Kitchener stitch as normal. The seam will be slightly less smooth than if you had left the stitches live, but it will still be far stronger and neater than a sewn seam.

Tension and Finishing the Seam

The most common mistake is pulling the yarn too tight while grafting. If you cinch the seam, it will pucker and the fabric on either side will bunch. Instead, keep the yarn loose as you work—loose enough that you can see the stitches forming clearly. Once you have finished the entire seam, go back and gently tighten it by pulling on the yarn tail, working from one end to the other. This distributes the tension evenly and prevents gaps.

When you reach the end of the seam, thread the yarn tail through the last stitch and pull it snug, then weave the tail into the seam itself for a few inches before trimming. This anchors the end and hides it within the seam.

Joining Pieces with Different Stitch Counts

Sometimes the two pieces you want to join do not have exactly the same number of stitches. This happens when you are joining a sleeve to an armhole, or when one piece has been shaped differently than the other. In these cases, you cannot use Kitchener stitch directly.

Instead, use a mattress stitch, which is a sewn seam worked from the right side of the fabric. Thread a blunt yarn needle with yarn that matches your knitting. Insert the needle under the horizontal bar between the first and second stitch on one piece, then under the corresponding bar on the other piece. Work up the seam, catching one bar from each side alternately. The seam will be nearly invisible and can accommodate slight differences in stitch count by skipping a stitch occasionally on the side with more stitches.

Mattress stitch is also the best choice for joining pieces where the edges are not live stitches—for example, joining the sides of a sweater body after you have cast off both edges.

Common Problems and How to Fix Them

If your Kitchener stitch seam has gaps, the yarn was too loose. You can tighten it by pulling gently on the yarn tail from the end of the seam, working backward toward the beginning. If the seam is puckered, the yarn was too tight. There is no straightforward fix for this—you will need to rip it out and redo it, but now you know to keep the tension looser.

If you accidentally drop a stitch while grafting, stop when ready and pick it back up with a crochet hook before continuing. A dropped stitch will unravel down the seam and create a ladder that is difficult to repair later.

If the two pieces do not line up evenly—one is slightly longer or shorter—you can adjust by skipping a stitch on the longer side occasionally. Do this gradually over several stitches rather than all at once, so the adjustment is not visible.

Frequently Asked Questions

Can I use Kitchener stitch if I have already cast off both pieces?

Yes, but you will need to pick the stitches back up first. Insert a needle through the bumps of the final row on each piece, working from one end to the other. It takes time, but the seam will still be nearly invisible once grafted.

What yarn should I use to graft the seam?

Use the same yarn you knitted the pieces with, or a yarn that matches in weight and color. If you do not have enough of the original yarn, a close match in color is more important than an exact fiber match, since the seam yarn will be hidden inside the fabric.

Is mattress stitch stronger than Kitchener stitch?

Both are strong, but they work differently. Kitchener stitch creates a seam by interlocking the stitches themselves, while mattress stitch is a sewn seam that runs between the columns of stitches. For pieces that will see stress—like underarms or side seams—either method is reliable if done correctly.

How do I know which joining method to use?

Use Kitchener stitch when both pieces have live stitches and you want an invisible seam. Use three-needle bind-off when you want a visible ridge or prefer speed. Use mattress stitch when pieces are already cast off, when stitch counts do not match, or when you are joining edges rather than live stitches.

What if my seam is uneven or lumpy?

Unevenness usually means the tension varied as you worked. Rip it out and redo it, focusing on keeping the yarn tension consistent throughout. If the seam is lumpy after grafting, you may have pulled too hard on the yarn tail when tightening—next time, distribute the tightening more gradually across the entire seam.