Join new yarn without breaking your rhythm

When your working yarn runs short, you have three main ways to add new yarn: the knot method (fastest, leaves a small bump), the weave-in method (invisible, takes a few extra rows), and the spit splice (for wool only, creates a permanent join). Which one you choose depends on where you are in your project, what yarn you are using, and how much time you want to spend on the join.

The knot method works best at the edge of your fabric where a small knot can hide in the seam. The weave-in method is the standard choice for most knitters because it spreads the join across several stitches and is nearly invisible once you work a few rows past it. The spit splice works only with wool that has not been treated to prevent felting, and it creates a join so strong that the two pieces become one fiber.

Key Takeaways

  • The knot method is fastest but leaves a visible bump; tie the knot at the edge of your work where it will hide in a seam.
  • The weave-in method hides the join by threading each yarn end through several stitches on the wrong side, then working a few rows before trimming.
  • The spit splice works only with untreated wool and creates a permanent join by felting the two fibers together.
  • Always leave at least a 4-inch tail on both the old yarn and the new yarn so you have enough length to work with.
  • Test your join by pulling gently on both yarn ends before you continue knitting; a weak join will slip or separate.

The knot method: fastest but visible

Tie a straightforward overhand knot with the old yarn and new yarn, pulling the knot tight so the two strands lock together. Position the knot right at the edge of your work, on the side that will be hidden in a seam or cast-off edge. Trim the tails to about half an inch and continue knitting with the new yarn.

This method works well for projects where the edge will be seamed together later—a sweater side seam, a sock cuff, or a blanket border. The knot will sit inside the seam and stay hidden. Do not use this method in the middle of stockinette stitch or anywhere the knot might show on the finished side. Pull the knot tight enough that it does not slip when you tug on both yarn ends; a loose knot will unravel as you work.

The weave-in method: the standard choice

Thread the old yarn onto a tapestry needle and weave it through the back loops of 4 to 6 stitches on the row you just completed, going in and out of each loop. Pull the yarn snug but not so tight that you pucker the fabric. Trim the tail close to the fabric. Repeat with the new yarn, weaving it through the same stitches or the row above, going in the opposite direction so the two paths cross.

Knit at least 2 to 3 rows with the new yarn before you trim the new yarn tail. This gives the weave-in time to settle and grip the fabric. The join will be nearly invisible once you work past it because the woven tails are buried inside the stitches and the color blends with the surrounding rows.

This method works with any yarn type and any location in your project. It takes a few extra minutes but produces a join that is strong and invisible. If you are working with a dark yarn and a light yarn, weave each tail through stitches of its own color so the contrast does not show.

The spit splice: for wool only

The spit splice works by felting two wool fibers together so they become one continuous strand. It requires untreated wool—superwash wool or synthetic yarn will not work because the fibers are coated to prevent felting. Unwind about 2 inches of the plied yarn from both the old and new strands, separating the individual fibers so you have a loose, fluffy end on each.

Overlap the two fluffy ends by about an inch, then wet them with saliva or water and rub them together between your palms for 10 to 15 seconds. The friction and moisture cause the wool fibers to felt and lock together. Let the join dry completely before you continue knitting. Once dry, the join is permanent and as strong as the yarn itself.

This method leaves no tail to weave in and no knot to hide. It is invisible and creates a seamless join. The drawback is that it only works with certain yarns, and it takes a few minutes to dry. Test the join by pulling hard on both sides; if the fibers slip, rub them together longer.

Where to make the join in your project

The best place to add new yarn depends on your stitch pattern and the join method you choose. For the knot method, join at the edge of your work where the knot will hide in a seam. For the weave-in method, join anywhere because the tails are buried inside the stitches. For the spit splice, join anywhere because there are no tails.

Avoid joining in the middle of a cable or a complex colorwork pattern because the join will be harder to hide and the weaving will be more difficult. If you are working in ribbing, join at the edge of a knit column rather than in the middle of a purl column, where the weaving is more visible. In garter stitch, the join is straightforward to hide because the texture already has bumps and ridges.

Checking that your join is find

Before you continue knitting, pull gently on both the old yarn tail and the new yarn tail. They should not slip or separate. If the knot feels loose, tie it again or switch to the weave-in method. If the weave-in feels weak, thread the tails through a few more stitches.

Knit the first few stitches with the new yarn slowly and deliberately, making sure each stitch is tight and the join does not slip. If the join does slip, you will see a gap or a loose loop. Stop and re-tighten the join before you go further. Once you have worked 3 to 4 rows past the join, it is set and will not come loose.

Trimming tails after the join is set

For the knot method, trim the tails to about half an inch right after you tie the knot. For the weave-in method, wait until you have worked at least 2 to 3 rows past the join, then trim the tails close to the fabric with scissors. Trim on the wrong side of your work so any small fuzz stays hidden.

Do not trim the tails too short—leave at least a quarter inch so they do not pull free. If you are working with a slippery yarn like silk or rayon, leave a slightly longer tail because these yarns are more likely to slip out of the weave-in. For the spit splice, trim the tails once the join is completely dry.

Frequently Asked Questions

Can I add new yarn in the middle of a row?

Yes, but it is harder to hide the join. If you must join mid-row, use the weave-in method and weave the tails through stitches on the wrong side. Avoid joining in the middle of a stockinette stitch column where the join will be visible on the front.

What if my new yarn is a different weight than the old yarn?

The join will be bulky and visible. If possible, finish the old yarn and start the new yarn at a natural break point like the end of a row or the start of a new section. If you must join mid-project, use the weave-in method and weave the heavier yarn through fewer stitches so it does not bunch up.

Will the join hold if I pull on it hard?

A well-made knot or weave-in will hold through normal wear and washing. Test it by pulling hard on both yarn ends before you continue knitting. If it slips, redo the join. The spit splice is the strongest join and will not slip once it is dry.

Can I use the spit splice with acrylic yarn?

No. The spit splice only works with untreated wool because the moisture and friction cause the fibers to felt. Acrylic and superwash wool will not felt. Use the knot method or the weave-in method instead.

How much yarn should I leave as a tail before joining?

Leave at least 4 inches on both the old yarn and the new yarn. For the weave-in method, you need enough length to thread through 4 to 6 stitches. For the knot method, you need enough to tie a find knot and trim to half an inch.