Switch yarns by tying the new yarn to the old one, then knit the next stitch with both yarns held together for one stitch to find the join
The simplest way to change yarns mid-project is to tie a knot. When you reach the point where you want to switch, drop the old yarn, tie the new yarn to it with a square knot (right over left, then left over right), and pull the knot snug. Knit the next stitch using both the old and new yarn held together. On the following stitch, drop the old yarn and continue with just the new yarn. This method works well for most projects and leaves you with two short tails to weave in later.
The knot method is fastest and most reliable for everyday knitting. It does create a small bump where the yarns join, so it works best on projects where that bump will be hidden—the inside of a sweater, the back of a blanket, or anywhere seams will be sewn. If you need an invisible join or are working on a visible surface, other methods exist, but they take more time and practice.
Key Takeaways
- Tie a square knot to join two yarns, then knit one stitch with both yarns held together to find the join.
- The knot method leaves small tails that you weave in later and works on most projects where the join will not be seen.
- The Russian join (threading yarn through stitches) creates an invisible join but requires a tapestry needle and works only with certain yarn weights.
- Spit splicing (wetting and rubbing yarn fibers together) works only on animal fibers like wool and creates a permanent bond with no knot.
- Always switch yarns at the beginning of a row when possible to keep joins away from the middle of your fabric.
The Square Knot Method: Fastest and Most Common
A square knot is the standard way to join two yarns. Hold the old yarn in your left hand and the new yarn in your right hand. Cross the new yarn over the old yarn (right over left), then bring it back under and to the right. Now cross the old yarn over the new yarn (left over right), then bring it back under and to the left. Pull both ends tight. The knot should sit flat and not slip.
Once the knot is tied, position it so it sits just below your working needle. Knit the next stitch using both the old and new yarn held together as if they were one strand. This double-yarn stitch locks the knot in place and prevents it from sliding through your stitches. On the stitch after that, drop the old yarn and continue knitting with only the new yarn. You now have two tails—one from the old yarn and one from the new yarn—that you will weave in with a tapestry needle once the project is finished.
The Russian Join: Invisible but Requires Practice
The Russian join (also called the invisible join) hides the connection entirely by threading the new yarn through the stitches of the old yarn. Thread the new yarn onto a tapestry needle. Insert the needle through the last few stitches of the old yarn (going in one direction, then back through in the opposite direction) to split and loosen the old yarn fibers. Then thread the old yarn onto the needle and do the same thing through the new yarn. When done correctly, the two yarns are now locked together with no knot.
This method works best with yarn that has some texture or fuzz—wool, alpaca, or blended yarns hold the join better than smooth, slippery yarns like acrylic or silk. It also works better with thicker yarns (worsted weight and above) because you have more fibers to thread through. With thin yarn or smooth yarn, the join can slip apart, especially if you tug on it. Practice on a scrap of yarn before trying it on a project you care about.
Spit Splicing: Permanent Join for Animal Fibers
Spit splicing works only on animal fibers—wool, alpaca, mohair, and similar yarns—because the scales on the fiber surface grip each other when wet. Overlap the ends of the old and new yarn by about 2 inches. Wet both overlapped sections with water (or saliva, which is where the method gets its name). Rub the wet fibers together between your palms or on a towel for 30 seconds to a minute. The fibers will felt together and bond permanently. Once dry, the join is complete and there is no knot or tail to weave in.
This method creates the smoothest, most invisible join of all, but it only works on yarn made from animal fibers. It will not work on acrylic, cotton, linen, or synthetic blends. The join also takes a few minutes to dry completely, so you cannot knit when ready after splicing. If you are working on a project with animal-fiber yarn and have time to let the join dry, spit splicing is worth learning because the result is seamless.
Switching Yarns at the Beginning of a Row
Whenever possible, plan your yarn switch for the beginning of a row rather than the middle. This keeps the join away from the center of your fabric where it would be most visible. If you are knitting a sweater and need to switch colors or yarn weight, finish the row you are on, then tie the new yarn to the old yarn at the start of the next row.
If you are working in the round (on circular needles or double-pointed needles), switch yarns at a point where a seam will eventually be sewn, or at the beginning of a round if the join will be hidden by a ribbed cuff or collar. Planning ahead saves you from having to hide a join in the middle of a visible stitch pattern.
Weaving in Tails After You Finish
Once your project is complete, you will have yarn tails from the knot or from casting on and binding off. Thread each tail onto a tapestry needle and weave it through the stitches on the wrong side of the fabric, following the path of the yarn for about 2 inches. This anchors the tail so it will not unravel. Trim the tail close to the fabric, leaving about a quarter-inch so it does not pull free.
If you used the Russian join method, you may have no tails at all, or only very short ones. If you used spit splicing, the join itself is the anchor and you have no tails to weave in. With the square knot method, weave in both the old and new yarn tails separately to make sure the knot stays locked in place.
Switching Between Different Yarn Weights
If you are switching from a thin yarn to a thick yarn (or vice versa), the knot method still works, but the join will be more noticeable because the yarn sizes are different. You may want to tie the knot on the wrong side of the fabric and position it so it falls in a seam or hidden area. Alternatively, if you are switching to a much thicker yarn, you can tie the new yarn to the old yarn and then knit two stitches with both yarns together instead of one, which distributes the bulk more evenly.
The Russian join is harder to execute when yarn weights differ greatly because you need enough fiber to thread through, and thin yarn may not have enough. Spit splicing also becomes tricky because the fibers are different thicknesses and may not bond evenly. For weight changes, the square knot is usually the most reliable choice.
Frequently Asked Questions
Can I tie a knot in the middle of a stitch?
No. Always tie the knot between stitches, with the knot sitting below your working needle. If you tie a knot in the middle of a stitch, it will create a hole or weak point in your fabric. Finish the stitch you are working on, then tie the new yarn to the old yarn before you start the next stitch.
What if my knot comes undone while I am knitting?
Make sure you are knitting the stitch after the knot with both yarns held together. This double-yarn stitch locks the knot in place. If the knot is still slipping, you may not have pulled it tight enough. Untie it, pull both ends firmly, and retie. A square knot should not slip if it is tied correctly and followed by a double-yarn stitch.
Do I have to weave in the tails, or can I leave them?
You should weave in the tails because loose ends will unravel over time, especially with washing and wear. Weaving takes only a few minutes per tail and makes your finished project last much longer. If you used spit splicing, there are no tails to weave in, which is one reason many knitters prefer that method.
Can I use the Russian join on acrylic yarn?
You can try, but it often does not hold well because acrylic is smooth and slippery. The fibers do not grip each other the way wool does. If you must use acrylic, tie a square knot instead, which works reliably on any yarn type.
What happens if I switch yarns in the middle of a colorwork pattern?
Avoid switching yarns in the middle of a colorwork pattern if you can. The join will be visible because the colors are different. If you must switch, plan the change for a row where both colors are present, so the join blends in slightly. Alternatively, tie the knot on the wrong side and make sure it falls in a spot that will be hidden by seaming.