The simplest way to shorten a knitted jumper
The fastest method is to try the jumper on, mark where you want the new hem to sit, then unpick the cast-off edge (the bound-off row at the bottom) and pull the yarn to unravel just the rows you don't need. Once you've removed the right number of rows, you pick up the live stitches on your needle and bind off again. This takes an hour or two and leaves you with a professional finish that matches the original.
If you're not comfortable unraveling and re-binding, you can also fold the excess fabric to the inside and hand-stitch it down, which hides the fold inside the jumper. This method is slower but safer if you've never worked with live stitches before.
Key Takeaways
- Unpicking the cast-off edge and re-binding is the cleanest method and takes about one to two hours for most jumpers.
- You need a needle the same size as the original knitting needles (check the ball band or measure the needle against the stitches) and matching yarn if you're re-binding.
- Folding and hand-stitching the hem is slower but works if you want to avoid unraveling, though it creates a visible double layer inside.
- Always try the jumper on and mark the new length with a pin or thread before you cut or unpick anything.
- If the jumper is a delicate yarn or you're unsure of your technique, a tailor can do this work for a fee that usually ranges based on yarn weight and jumper size.
Marking the right length before you start
Put the jumper on inside-out and have someone pin or mark where you want the new hem to fall. If you're alone, put it on right-side out in front of a mirror and use a safety pin or a piece of contrasting thread to mark the spot. The mark should be level all the way around—use a ruler or measuring tape held horizontally to check.
Measure from that mark down to the current hem and write the number down. This is how many rows you need to remove. Count the rows in the knit (each horizontal line is one row) to make sure your measurement matches. If the jumper is ribbed at the hem, count only the main body rows, not the ribbing.
Unpicking the cast-off edge and unraveling rows
Lay the jumper flat on a table with the hem facing you. Find where the yarn was cut when the jumper was finished—this is usually a small tail on one of the edge stitches. Gently pull this tail and the stitches will begin to unravel. Pull slowly and keep the yarn in a loose coil so it doesn't tangle.
Stop when you've unraveled the number of rows you marked. You should now see a row of live stitches (loops still on the yarn, not bound off). Smooth these stitches out and count them to make sure you have the same number as the original cast-on.
If you accidentally unravel too far, you can re-knit the rows back up using the yarn you pulled out, though this is fiddly. It's easier to be conservative and unravel one row at a time, checking your progress as you go.
Picking up stitches and binding off
Thread the live stitches onto a needle that matches the size of the original needles. If you don't have the original needles, measure the needle diameter against the stitches in the body of the jumper—they should be roughly the same width as the needle. The ball band (the label on the yarn) usually lists the needle size if you still have it.
Once all stitches are on the needle, bind off using the same method the original jumper used. Most jumpers use a basic bind-off: knit two stitches, pass the first stitch over the second, knit one more, pass the first over the second, and repeat until one stitch remains. Cut the yarn, pull it through the last stitch, and weave the tail into the edge stitches with a tapestry needle.
If you don't have matching yarn, you can use a similar weight and color—the bind-off edge will be slightly visible but blends in once the jumper is worn. Avoid yarn that's much thicker or thinner, as it will look out of place.
Folding and hand-stitching as an alternative
If you prefer not to unravel, fold the excess fabric to the inside of the jumper along your marked line. Pin the fold in place and try the jumper on to confirm the length is right. Adjust if needed.
Thread a needle with matching yarn and use a ladder stitch (also called an invisible stitch) to sew the folded edge to the inside of the jumper body. Work from inside the jumper, catching just a few fibers of the fold and then a few fibers of the body, alternating back and forth. This creates a seam that's hidden inside and doesn't show from the outside.
This method takes longer than unraveling—usually two to four hours depending on the jumper's width—but it's safer if you're nervous about working with live stitches. The downside is that the inside of the jumper now has a double layer of fabric, which can feel bulky.
When to take it to a tailor instead
If the jumper is made from delicate yarn (lace, mohair, or very fine merino), has a complex stitch pattern, or you're not confident with the techniques above, a tailor or alterations specialist can shorten it for you. They usually charge based on the yarn weight and jumper width, though prices vary by location and tailor.
A tailor will typically use the unraveling method or a professional serger to finish the edge, depending on the yarn type. Call ahead and ask if they have experience with hand-knits, as some tailors work mainly with woven fabrics and may not be familiar with knit construction.
Frequently Asked Questions
What if I can't find the yarn tail to start unraveling?
If the tail is missing or too short to grip, carefully cut one stitch at the cast-off edge with small scissors and gently pull the yarn. The stitches will unravel from that point. Work slowly to avoid splitting the yarn.
Can I shorten a jumper with ribbing at the hem?
Yes, but you'll need to decide whether to keep the ribbing or remove it too. If you remove rows from the ribbed section, the ribbing will be shorter and may look odd. Most people remove the same number of rows from both the ribbing and the main body, or remove only from the main body and leave the ribbing as-is.
What needle size should I use if I don't have the original needles?
Measure the needle diameter against the stitches in the jumper body—the needle should slide through the stitches without forcing them. The ball band usually lists the needle size. If you've lost the label, a yarn shop can help you match the size by comparing your jumper to a needle gauge.
Will the new hem look different from the original?
If you use the same yarn and bind-off method, the new hem will be nearly identical to the original. If you use different yarn, the bind-off edge may be slightly visible but will blend in with wear. Folded hems are always visible from the inside but invisible from the outside.
How long does this usually take?
Unraveling and re-binding takes one to two hours for most jumpers. Folding and hand-stitching takes two to four hours. A tailor typically takes one to two weeks, depending on their workload.