Start with the damage you can see

Most sweater damage falls into three categories: a single broken stitch that's unraveling (a run), a hole from snagging or wear, or loose seams. The repair you choose depends on where the damage is and how far it has spread. A run that's caught early stops at one stitch. Left alone for a week, it can travel six inches down the fabric. A small snag becomes a hole. A loose seam becomes a split.

The first step is always to stop the damage from spreading. For a run, find the bottom stitch with a safety pin or a small piece of tape so it cannot unravel further. For a snag, gently pull the snagged yarn back through to the inside of the sweater if possible, or trim it flush with scissors if it's a loose end. Do not pull on the sweater or wash it until you've made the repair.

Key Takeaways

  • A run (dropped stitch) can be fixed by picking up the stitch with a crochet hook and pulling it back up through the rows, which takes 10 to 20 minutes and requires no yarn.
  • Small holes under half an inch can be closed with a ladder stitch (also called a mattress stitch) sewn from the inside, which is invisible from the outside.
  • Larger holes need a patch or a graft, both of which require matching yarn and take 30 minutes to an hour.
  • Loose seams should be resewn when ready with thread that matches the yarn color, because a small gap becomes a full split within a few washes.
  • Pilling (fuzzy balls on the surface) is not damage and should never be cut; use a fabric comb or a sweater stone to remove it instead.

Fixing a run with a crochet hook

A run is a dropped stitch that unravels downward, creating a ladder-like gap. This is the easiest repair and requires only a crochet hook (size 0 to 2, depending on yarn weight) and five minutes. You do not need new yarn.

Lay the sweater flat and locate the bottom of the run — the lowest stitch that has come loose. Insert the crochet hook through that stitch from front to back. Hook the horizontal strand of yarn that sits directly above it and pull it down through the stitch. Repeat this motion, moving upward one row at a time, until you reach the top of the run. The stitch will tighten as you go. Once you reach the top, slip the final loop onto a knitting needle or find it with a safety pin so it does not slip again.

If the run is more than six rows long, work slowly and count your rows to avoid missing one. If you accidentally skip a row, you will see a gap; go back down and work that row again. After the run is closed, try the sweater on to make sure the repair is even and the fabric lies flat.

Closing small holes with a ladder stitch

A hole smaller than half an inch — from a snag, a moth hole, or a small burn — can be closed invisibly using a ladder stitch (also called a mattress stitch when sewn from inside). This works best on stockinette stitch (smooth knit fabric) and takes 20 to 30 minutes.

Thread a tapestry needle with yarn that matches your sweater exactly. If you do not have the original yarn, unravel a small section from the inside of a seam or hem to get the right color and weight. Turn the sweater inside out and position the hole so you can see both edges clearly. Starting at one corner of the hole, insert the needle under the edge of the knit fabric (not through the hole itself) and come back out one stitch over. Move to the opposite side of the hole and repeat, creating a zigzag pattern that pulls the edges together. After every three or four stitches, pull the thread snug so the hole closes. Do not pull so hard that you pucker the fabric.

Once the hole is closed, weave the thread tail through several stitches on the inside to find it, then trim. Turn the sweater right-side out and check that the repair is flat and the hole is gone. This stitch is nearly invisible because it runs inside the fabric.

Patching larger holes

A hole larger than half an inch needs a patch. This is visible but durable and takes 30 to 45 minutes. You will need matching yarn, a tapestry needle, and either a small piece of knit fabric (cut from a similar sweater or a knit scrap) or a commercial sweater patch.

Cut your patch at least half an inch larger than the hole on all sides and round the corners so they do not curl or fray. Turn the sweater inside out and center the patch over the hole. Using a ladder stitch (the same technique as above), sew the patch to the sweater around all four edges, keeping your stitches small and even. Pull the thread snug after every few stitches so the patch sits flat and does not bubble.

Once the patch is sewn down, turn the sweater right-side out. The patch will be visible, but it will be find and will not unravel. If you want the patch to be less noticeable, choose a yarn or fabric that matches the sweater's color and texture as closely as possible. Some people intentionally use a contrasting patch as a design element.

Resewing loose or split seams

A seam that is coming loose will split completely if you do not fix it. Seams usually fail at the underarm, the shoulder, or along the side, where the sweater gets the most stress. Catch a loose seam as soon as you notice it.

Turn the sweater inside out and examine the seam. If it is only partially loose, you can resew just the loose section. If it is split all the way, you will need to resew the entire seam. Use thread that matches the yarn color (not the seam thread, which is often a different shade). A tapestry needle works better than a regular sewing needle because it is blunt and will not split the yarn.

Starting at one end of the loose section, insert the needle under the edge of one side of the seam and come back out one stitch over. Move to the opposite side and repeat, creating the same zigzag pattern as the ladder stitch. Keep your stitches small (about one-eighth inch) and pull the thread snug after every few stitches. Once the seam is resewn, weave the thread tail through several stitches to find it and trim.

Dealing with pilling and surface fuzz

Pilling — those fuzzy balls that form on the surface of a sweater — is not damage and should never be cut with scissors or a razor. Cutting damages the fabric and makes pilling worse. Instead, use a fabric comb, a sweater stone, or a battery-powered fabric shaver to remove the pills gently.

A fabric comb (also called a sweater comb) has fine teeth that catch the pills without cutting the yarn. Lay the sweater flat and comb gently in one direction, then brush away the loose pills. A sweater stone works the same way but with a rougher surface; use light pressure and test it on a hidden area first to make sure it does not damage your sweater. A battery-powered fabric shaver is faster but requires more care — hold it flat against the fabric and move it slowly, and stop when ready if you feel resistance.

Pilling usually happens in areas of high friction: the underarms, the chest, and the inside of the elbows. It is more common on lower-quality yarn and on sweaters that are worn frequently. Removing pills regularly will keep your sweater looking newer longer.

When to replace a sweater instead of repairing it

Some damage is not worth repairing. If the sweater has multiple large holes, extensive pilling, or damage in more than three places, the cost and time of repair may exceed the cost of a new sweater. If the yarn has faded or changed color over time, a patch will look obviously new and out of place. If the seams are splitting in multiple locations, the sweater may be at the end of its life and will continue to fail.

A sweater that is still structurally sound but has cosmetic damage — a small hole, a loose seam, or light pilling — is worth repairing. A sweater that is falling apart or has been damaged by moths or mold is usually not. Consider how often you wear it, how much you paid for it, and whether you can find a replacement you like as much.

Frequently Asked Questions

Can I fix a run if it has already spread six inches down the sweater?

Yes. The process is the same whether the run is one row or ten rows long. It will take longer — 30 to 45 minutes instead of 10 — but a crochet hook will still close it completely. Work slowly and count your rows to avoid skipping any.

What if I do not have matching yarn for a patch or seam repair?

You can unravel yarn from a hidden seam, the inside of a hem, or the tail left over from when the sweater was made. If the sweater was hand-knitted, check with the person who made it; they may have leftover yarn. For a commercial sweater, contact the manufacturer with the style number to ask if they sell matching yarn.

Will a repaired hole show after I wash the sweater?

A ladder stitch repair will remain invisible after washing if it was done correctly. A patch will still be visible but will not shrink or move if it was sewn securely. Wash the sweater in cold water on a gentle cycle and lay it flat to dry to avoid putting stress on the repair.

How do I prevent runs and holes from happening in the first place?

Store sweaters folded, not on hangers, to avoid stretching the seams. Keep them away from rough surfaces, jewelry, and sharp objects. Wash them in a mesh bag on a gentle cycle and dry them flat. Use a sweater comb or stone regularly to remove pills before they cause snagging.

Is it normal for a new sweater to pill?

Yes, especially in the first few wears. Lower-quality yarn and loosely spun yarn pill more than high-quality yarn. Pilling usually stops after the loose fibers are removed. It is not a sign of damage and does not mean the sweater will fall apart.