Skipped stitches mean the needle is missing the bobbin thread at the moment it should lock it in place

When your sewing machine skips stitches, it creates gaps in your seam where no thread locked down. This happens because the needle and bobbin thread aren't meeting at the right time and position. The needle passes through the fabric, but the bobbin hook—the small curved piece that catches the needle thread—misses it entirely. The result is a weak seam that can unravel, especially under stress.

Skipped stitches are almost always fixable without a repair shop visit. The problem is usually one of four things: the needle is bent or inserted wrong, the thread tension is off, lint is blocking the bobbin area, or the needle is the wrong size for your fabric. Start by checking these in order, because each one is quick to test.

Key Takeaways

  • A bent needle or one inserted backward will cause skipped stitches every time—replace it and reinsert it with the flat side facing the correct direction for your machine.
  • Thread tension that is too tight or too loose prevents the needle and bobbin thread from locking properly, so test both upper and lower tension before assuming the needle is damaged.
  • Lint and thread bits clogging the bobbin area block the hook from catching the needle thread, so clean under the presser foot and around the bobbin case weekly.
  • Using a needle too small or too large for your fabric weight causes the thread to slip past the hook, so match needle size to fabric type.
  • If skipped stitches happen only on certain fabrics or only in one area of a seam, the problem is usually tension or needle size, not a mechanical fault.

Check and replace the needle first

A bent needle is the most common cause of skipped stitches, and it is also the easiest to fix. Hold the needle up to a light source and look down its length. Even a tiny bend—one you cannot feel with your fingers—will throw off the timing between the needle and the bobbin hook. If you see any bend at all, replace it.

Even if the needle looks straight, it may be inserted wrong. Every sewing machine has a specific way the needle must face. Most machines require the flat side of the needle to face toward the back or toward one side—check your manual or look at the needle clamp itself, which often has a small arrow or line showing the correct direction. Remove the needle, reinsert it with the flat side facing the right way, and tighten the clamp firmly. A loose needle will also skip stitches.

Replace the needle with a fresh one from a new package. Needles wear out and develop tiny burrs that catch thread unevenly. If you have been using the same needle for more than a few hours of sewing, swap it out. Universal needles work for most cotton and blended fabrics, but if you are sewing knits, stretch fabrics, or heavy materials like denim, use a needle designed for that fabric type.

Adjust thread tension on both the upper and lower mechanisms

Thread tension controls how tightly the upper thread pulls on the lower thread as they lock together. If the upper tension is too tight, it pulls the needle thread so hard that the bobbin hook cannot catch it. If it is too loose, the needle thread is slack and the hook misses it. The same problem happens with lower tension—the bobbin thread must be taut enough to meet the needle thread at the right moment.

Start with upper tension. Most machines have a numbered dial on the front or side, usually marked 0 to 9. The default is usually around 4 or 5. If you are skipping stitches, try moving it down one or two numbers and test on scrap fabric. Sew a few inches and look at the seam. If stitches are still skipping, try moving the dial up instead. Make small adjustments—one number at a time—until stitches lock evenly.

Lower tension is less obvious but equally important. The bobbin case has a small screw that controls how much the thread can pull through. This screw is tiny and straightforward to overtighten, so most people leave it alone unless they have already ruled out everything else. Before you touch it, make sure your bobbin is wound evenly and inserted correctly—a bobbin that is not seated all the way in the case will cause skipped stitches. If the bobbin is in correctly and upper tension adjustments did not help, try loosening the bobbin case screw a quarter turn and test again.

Clean lint and thread scraps from the bobbin area

Lint builds up around the bobbin case and under the presser foot, blocking the hook from moving freely. When the hook cannot move smoothly, it cannot catch the needle thread at the right moment. This is especially common if you sew a lot of cotton or fleece, which shed fibers constantly.

Raise the presser foot—this opens the tension discs so you can access the area underneath. Use a small brush (many machines come with one) or an old toothbrush to sweep out lint from under the presser foot and around the bobbin case. Pay special attention to the small curved hook itself. If lint is packed in tight, use a wooden toothpick to gently dislodge it, then brush it away. Do not use a metal tool, which can scratch the hook.

Make this a weekly habit if you sew regularly. A quick cleaning takes less than a minute and prevents most tension and skipping problems before they start.

Match needle size to your fabric weight

Needles come in sizes from 60 to 120, and the number tells you the needle diameter. A size 60 needle is very thin and works for lightweight fabrics like silk and voile. A size 100 is medium and handles most cotton quilting fabric. A size 120 is thick and designed for heavy materials like denim, canvas, or upholstery fabric.

If your needle is too small for the fabric, the thread will not sit properly in the needle's groove, and the bobbin hook will miss it. If the needle is too large, it creates a hole bigger than the thread, and the thread can slip sideways. Check the needle package to see what fabric weight it is rated for, and match it to what you are sewing. If you are working with a blend—say, a cotton-linen mix—use a needle one size up from what you would use for pure cotton.

Test on different fabric and thread combinations

Sometimes skipped stitches happen only with certain fabrics or thread types. If you notice the problem only when sewing knits, or only with thick thread, or only on one particular fabric you own, the issue is usually needle size or tension rather than a broken machine.

Thread quality matters too. Cheap or old thread becomes brittle and frays easily, which can jam the bobbin hook or cause the needle to miss. If you have been using the same spool for a long time, try a fresh spool of good-quality thread and test again. Polyester thread is more forgiving than cotton thread on most machines, so if you are having trouble with cotton, switching to polyester can help you narrow down whether the problem is the thread itself.

Sew a test seam on scrap fabric that matches what you are working on. Sew slowly and watch the needle and presser foot area as you go. If stitches skip only on certain fabrics, you now know the problem is not a mechanical fault—it is a mismatch between needle size, tension, and fabric.

When to stop troubleshooting and call a repair person

If you have replaced the needle, cleaned the bobbin area, adjusted tension on both upper and lower mechanisms, and tested with different thread and fabric, and stitches still skip on every fabric you try, the machine likely has an internal timing problem. The hook and needle are no longer synchronized, which means the bobbin hook is not in the right position when the needle passes through. This is a mechanical issue that requires a technician to adjust.

Also call a repair person if you see the bobbin hook itself is bent or chipped, or if the needle clamp is cracked. These parts cannot be fixed at home and will cause skipped stitches no matter what you adjust.

A repair visit usually costs between $50 and $150 depending on what needs fixing. Many shops offer a free diagnostic, so you can call ahead and describe the problem before bringing the machine in.

Frequently Asked Questions

Can old thread cause skipped stitches?

Yes. Thread that has been stored in sunlight or heat becomes brittle and frays as it passes through the needle and tension discs. The frayed bits jam the bobbin hook or cause the thread to slip. If you have had the same spool for more than a year or two, try a fresh one before assuming the machine is broken.

Why do stitches skip only on thick fabrics like denim?

Thick fabric requires a larger needle to penetrate without bending. If you are using a size 80 needle on denim, switch to a size 100 or 110. Also check that your upper tension is not too tight—thick fabric needs slightly looser tension than lightweight cotton so the thread does not break or skip.

Does needle direction matter on every machine?

Yes. Every machine has a correct needle orientation, though the direction varies by brand. Check your manual or look for a small arrow or line on the needle clamp itself. Inserting the needle backward is one of the quickest ways to cause skipped stitches.

What is the difference between skipped stitches and broken thread?

Skipped stitches leave gaps in the seam where no thread locked down—the seam looks incomplete. Broken thread snaps and leaves a loose end. Broken thread usually means tension is too tight or the needle is bent. Skipped stitches mean the needle and bobbin thread are not meeting at the right moment.

Should I adjust the bobbin case screw if I am not sure what I am doing?

Only as a last resort. The screw is straightforward to overtighten, which makes the problem worse. If you do adjust it, turn it only a quarter turn and test. If that does not help, turn it back to where it was. Most skipped stitch problems are solved by needle replacement, cleaning, or upper tension adjustment alone.