Measure and mark the new hemline before you cut
The first step is deciding how much fabric to remove. Put on the shirt and have someone measure from the bottom edge up to where you want the new hem to sit—usually at your hip or mid-thigh, depending on the style. Mark that line with tailor's chalk or a fabric pencil all the way around the shirt while wearing it, or lay the shirt flat and measure up from the bottom edge using a ruler or measuring tape.
Once you have marked the line, add half an inch to that measurement. That extra half inch is the hem allowance—the fabric that will fold under and be sewn. So if you want the visible hem to sit 2 inches from the bottom, you will cut at 2.5 inches. This allowance keeps the stitches hidden inside the fold.
Cut straight across using sharp fabric scissors or a rotary cutter and ruler. A crooked cut makes the hem sit unevenly, so take your time here. If the shirt has a curved hem (most do), cut parallel to the original edge rather than trying to follow the curve exactly—you will adjust the curve when you fold and pin.
Key Takeaways
- Measure and mark the hemline while wearing the shirt or by laying it flat, then add a half-inch allowance before cutting.
- Fold the raw edge under twice—first a quarter inch, then another half inch—to hide the cut edge inside the fold.
- Pin the folded hem in place all the way around, checking that the fold sits at the same distance from the bottom edge everywhere.
- Sew the hem with a straight stitch about a quarter inch from the inner fold, using a thread color that matches the shirt fabric.
- Press the finished hem with an iron set to the heat level safe for your fabric to make the stitches sit flat.
Fold the raw edge under twice to hide it
Lay the shirt flat on your work surface with the wrong side (inside) facing up. Fold the cut edge up a quarter inch and press it with your fingers or an iron to crease the fold. This first fold hides the raw, frayed edge.
Now fold that creased edge up another half inch and press again. You now have a folded hem with the raw edge completely hidden inside. This double fold is the standard method because it prevents fraying and looks neat from the inside of the shirt.
If your shirt has a curved hem, the fold will bunch slightly at the curves. This is normal. Smooth it out as you go, and the bunching will disappear once you sew. Do not try to make the fold perfectly smooth before sewing—the stitching will hold it in place.
Pin the hem in place all the way around
Use straight pins or quilting pins to hold the folded hem against the shirt body. Place pins every 3 to 4 inches, perpendicular to the fold (so the pin goes through the fold and into the shirt body). Pin all the way around the shirt.
Before you sew, check that the fold sits at the same distance from the bottom edge everywhere. Lay the shirt flat and measure from the edge to the fold in three or four places. If the distance varies, adjust the pins until it is even. An uneven hem will be visible when you wear the shirt.
Remove the pins as you sew—do not sew over them, as this can break your needle or damage the machine.
Sew the hem with a straight stitch
Thread your machine with thread that matches the shirt fabric. If you cannot find an exact match, choose a shade slightly darker than the fabric—darker thread is less visible than lighter thread. Wind a bobbin with the same thread.
Set the machine to a straight stitch with a stitch length of 2 to 2.5 millimeters. This length is small enough to hold the hem securely but large enough to be strong. Test the stitch on a scrap of fabric first if you are unsure about your machine's settings.
Position the shirt under the presser foot so the needle will sew about a quarter inch from the inner fold of the hem. Sew slowly and steadily all the way around the shirt, removing pins as you approach them. Backstitch at the beginning and end to lock the thread.
If your shirt has a curved hem, the outer edge will curve more than the inner fold. This is fine—just follow the fold with your needle and let the fabric ease naturally. The curve will sit flat once the hem is pressed.
Press the finished hem to set the stitches
Set your iron to the heat level safe for your fabric. Check the shirt's care tag—cotton and linen can take medium to high heat, while synthetic fabrics need low to medium heat. If you are unsure, start with medium heat.
Lay the shirt flat with the wrong side up and press the hem firmly for 10 to 15 seconds. Flip the shirt over and press the right side as well. The heat sets the stitches and makes them sit flat against the fabric, so the hem will look smooth and professional.
Let the shirt cool completely before wearing or washing it. The stitches need time to set, especially if you used a synthetic thread.
Troubleshoot common hemming problems
If the hem puckers or bunches, the thread tension may be too tight. Loosen the top tension slightly and test on a scrap before hemming again. Puckering can also happen if you pulled the fabric while sewing—let the machine feed the fabric at its own pace.
If the stitches are visible from the outside of the shirt, you sewed too far from the fold. The stitches should sit in the fold itself or just barely outside it. On your next hem, position the needle closer to the fold.
If the hem sits unevenly (higher on one side than the other), the original cut was crooked or the fold was not pinned evenly. You can unpick the stitches with a seam ripper, re-pin the hem, and sew again. Sewing machines make this straightforward—there is no penalty for starting over.
Frequently Asked Questions
Can I hem a shirt without cutting it?
Yes, if the shirt is only slightly too long. Fold the hem up to the desired length, pin it, and sew without cutting. The hem will be thicker because you are sewing through more layers, but it works for small adjustments. You will need to fold the raw edge under to prevent fraying, so the total fold will be about an inch thick.
What if I sew the hem crooked?
Use a seam ripper to cut and remove the stitches, then re-pin and sew. Seam rippers are inexpensive and make this task quick. There is no shame in unpicking and resewing—even experienced sewers do this regularly.
Should I use a special presser foot for hemming?
A standard presser foot works fine for most hems. Some machines have a walking foot or even-feed foot, which helps feed thick or slippery fabrics evenly, but it is not required. Stick with your regular foot unless you notice the fabric bunching or shifting as you sew.
Can I hem a knit shirt the same way?
Knits need a slightly different approach because they stretch and can curl at the edges. Use a ballpoint needle (designed for knits) and a stretch stitch or narrow zigzag instead of a straight stitch. The stretch stitch moves with the fabric and prevents the hem from breaking when you wear the shirt.
How do I know if my hem is the right length?
The best way is to wear the shirt and have someone measure while you stand in your normal posture and shoes. The hem should sit where you marked it before cutting. If you hemmed it and it is too short, you cannot add length back—you would need to buy new fabric or live with it. Measure twice, cut once.