Adding yarn means joining a new ball or skein to your work without breaking the thread

When you run out of yarn mid-project, you have three main ways to join a new ball: the weave-in method (the most common), the knot method (fastest but visible), and the Russian join (invisible and strong). The method you choose depends on whether you care if the join shows, how much time you have, and whether you're working with wool, cotton, or synthetic yarn. Most knitters use the weave-in method because it's nearly invisible and works with any yarn type.

The key difference between these methods is when you do the work. The weave-in method requires you to finish your project, then thread the yarn ends back through stitches you've already made. The knot method ties the yarns together while you're still knitting, so you keep going when ready. The Russian join uses a needle to thread one yarn through the other before you even cast on or pick up stitches.

Key Takeaways

  • The weave-in method works by threading your old and new yarn ends through finished stitches with a tapestry needle after you've switched yarns, making the join nearly invisible.
  • The knot method ties the two yarns together with a square knot while you're still at your needles, letting you keep knitting when ready but leaving a small bump in your fabric.
  • The Russian join threads one yarn through the other using a tapestry needle before you attach the new yarn, and works best with wool and other fuzzy fibers that grip themselves.
  • All three methods work with any yarn weight, but fuzzy yarns like wool hide joins better than smooth yarns like cotton or acrylic.
  • You should always add yarn at the beginning of a row or round, never in the middle of a stitch, so the join sits at an edge where it's less noticeable.

The Weave-In Method: Invisible and Reversible

The weave-in method is the standard choice for most knitters because the join disappears into your finished fabric. You work until you run out of yarn, switch to your new ball, and keep knitting. Later—after you've finished the whole project or at least a few more rows—you thread both yarn ends through a tapestry needle and weave them back through the stitches you've already made.

Here's the step-by-step process. First, thread your old yarn end (the one you just finished with) onto a tapestry needle. Starting a few stitches before where you switched yarns, weave the needle horizontally through the bumps on the back of your stitches, going in and out of the loops without splitting the yarn. Weave for about two inches, then reverse direction and weave back over the same path, creating a zigzag. Trim the end close to the fabric. Repeat the same process with your new yarn end, starting a few stitches after where you switched. The two woven paths anchor each yarn end so it won't unravel.

This method works best after you've knitted at least a few more rows past the join, because the tension of those new stitches helps hold the woven ends in place. If you're working on a project where you'll block it (wet it and pin it to shape), blocking also helps set the woven ends. The weave-in method is completely reversible—if you make a mistake, you can pull the yarn back out and try again.

The Knot Method: Fast but Visible

The knot method ties your old and new yarn together with a square knot while you're still holding your needles. This is the fastest way to add yarn because you tie the knot, position it on the wrong side of your work, and keep knitting when ready without waiting to finish rows or the whole project.

To tie a square knot, hold the old yarn in your left hand and the new yarn in your right hand. Cross the new yarn over the old yarn, wrap it around, and pull it through to make a loop. Then cross the old yarn over the new yarn, wrap it around, and pull it through. Tighten by pulling both yarn ends away from the knot. The knot should sit on the wrong side (the back) of your work, not the front. Position it so it sits just behind your working stitches, then continue knitting with the new yarn.

The downside is that the knot creates a small bump in your fabric that you'll see if you look closely, especially on the wrong side. The bump is usually hidden if it lands on a seam or edge that gets sewn together later. This method works well for projects where the join will be hidden—like the underarm of a sweater or the inside of a hat—but not for visible areas like the front of a blanket. The knot is also permanent; you can't undo it without cutting the yarn.

The Russian Join: Invisible and Permanent

The Russian join threads one yarn through the other using a tapestry needle, creating a join that's as strong as the yarn itself. This method works best with wool and other fuzzy fibers because the fibers grip each other and hold the join tight. It's less reliable with smooth yarns like cotton or acrylic, which can slip apart.

Here's how to do it. Thread your new yarn onto a tapestry needle. Insert the needle into the old yarn, going lengthwise through the center of the yarn (not through individual plies, but through the hollow core if there is one). Push the needle through about two inches of yarn, then pull the needle out. Now thread the old yarn onto the tapestry needle and repeat the process, pushing the needle through the new yarn. When you pull both yarns tight, they lock together. Trim the short ends close to the join.

The Russian join is invisible because there's no knot—the yarns are straightforward threaded through each other. It's also very strong and won't come undone with normal wear. The downside is that it takes a bit of practice to get the tension right, and it doesn't work well with thin yarns or smooth fibers. You also need to do this join before you start knitting with the new yarn, so it's best used when you're adding yarn at the very beginning of a project or at a planned color change.

When to Add Yarn: Position Matters

Always add yarn at the beginning of a row or round, never in the middle of a stitch. This keeps the join at an edge where it's less noticeable and easier to weave in later. If you're knitting flat (back and forth), add yarn at the start of a row. If you're knitting in the round, add yarn at the start of a round.

Plan ahead so you don't run out of yarn mid-row. A good rule is to add yarn when you have about three times the width of your project left in your current ball. For example, if your sweater is 20 inches wide, add yarn when you have about 60 inches (five feet) of yarn remaining. This gives you enough yarn to finish the row without running short.

If you do accidentally run out of yarn in the middle of a row, you have two choices: pull out stitches back to the beginning of the row and start over, or tie a temporary knot to hold your stitches, add yarn using the knot method, and plan to weave in the ends later. The first option is cleaner but takes more time. The second option is faster but leaves a knot you'll need to hide.

Yarn Types and How They Affect Your Join

Fuzzy yarns like wool, alpaca, and mohair hide joins beautifully because the fibers grip each other and blur the line where two yarns meet. These yarns work well with all three methods, though the Russian join is especially effective because the fibers lock together naturally.

Smooth yarns like cotton, acrylic, and silk show joins more clearly because there's nothing to grip or blur the transition. With these yarns, the weave-in method is your best choice because you can weave the ends through multiple rows, creating a longer anchor that won't slip. Avoid the Russian join with smooth yarns because the fibers will slide apart. The knot method works but will be more visible.

Variegated or multi-colored yarns can hide joins better than solid colors because the color changes distract the eye. If you're using a variegated yarn, try to add the new ball when the color is changing, so the join lands in a spot where the color is already shifting.

Common Mistakes and How to Avoid Them

The most common mistake is adding yarn in the middle of a stitch or row, which makes the join bulky and hard to hide. Always finish the stitch you're working on, complete the row, and then switch to the new yarn at the beginning of the next row.

Another mistake is not leaving long enough yarn ends to weave in. When you switch yarns, leave at least four inches of the old yarn and four inches of the new yarn. If the ends are too short, you won't have enough to thread through your tapestry needle or weave through stitches. If you accidentally cut the ends too short, you can tie a small knot at the end of the yarn to keep it from unraveling, then weave in what you have.

A third mistake is weaving in the ends too soon, before the new stitches have set. If you weave in your yarn ends right after switching yarns, the tension might shift as you knit more rows, and the woven ends can work loose. Wait until you've knitted at least three or four more rows past the join before you weave in the ends.

Finally, don't pull too hard when you tie a square knot. If you pull too tight, you'll create a bulge in your fabric. Pull just hard enough so the knot is snug but not strangling the yarn.

Frequently Asked Questions

Can I add yarn in the middle of a row?

You can, but it's not recommended because the join will be bulky and visible. If you run out of yarn mid-row, your best option is to pull out stitches back to the beginning of the row and start over. If you're in a hurry, tie a temporary knot to hold your stitches, add the new yarn, and plan to hide the knot later when you weave in the ends.

How long should I leave the yarn ends when I switch?

Leave at least four inches of each yarn end—the old yarn and the new yarn. This gives you enough length to thread onto a tapestry needle and weave through several stitches. If you're using a very thick yarn, leave six inches. If the ends are shorter than two inches, they're too short to weave in safely.

What if my yarn ends keep slipping out when I weave them in?

This usually happens with smooth yarns like cotton or acrylic. Weave the ends through more rows—aim for at least three inches of weaving instead of two. You can also weave in a zigzag pattern (going in and out of stitches) rather than a straight line, which creates more grip. If the yarn still slips, try the knot method instead.

Do I have to weave in the ends right away?

No. You can weave in the ends anytime after you've knitted a few more rows past the join. Many knitters wait until the whole project is finished, then weave in all the ends at once. This is actually better because the tension of the finished fabric helps hold the woven ends in place.

Can I use the Russian join with all yarn types?

The Russian join works best with fuzzy yarns like wool, alpaca, and mohair. It's less reliable with smooth yarns like cotton or acrylic because the fibers can slip apart. With smooth yarns, stick with the weave-in method instead.