How to Sew a Blind Hem Stitch by Hand
The blind hem stitch takes up less than a thread's width of the outer fabric, so from the right side the hem is almost invisible. It is the hand-sewn answer to a machine blind hem, and it is worth learning for trousers, skirts and curtains where a visible stitch line would ruin the finish. The trick is to catch only one or two fibres of the outer layer with each stitch.
Materials
- Wool, cotton or poly-viscose trouser and skirt fabric
- Fine matching thread
- Tailor's chalk (optional)
Tools
- Fine hand needle (sharps size 9 to 10)
- Pins
- Iron and pressing cloth
Steps
- 01
Press the hem allowance
Turn the hem up by the amount you want, about 3 cm for a skirt and 4 to 5 cm for trousers, and press the fold firmly with steam. Then turn the raw edge under by 1 cm and press again so the raw edge is enclosed. A crisp pressed fold is half the battle with an invisible hem.
- 02
Pin and check the length
Pin the hem every 5 cm, with the pins angled along the fold rather than across it so they do not distort the line. Try the garment on or hold it against you and check the hem is level all round. Fix any length problems now, because unpicking a blind hem leaves marks.
- 03
Anchor the thread inside the fold
Thread a fine needle with about 40 cm of matching thread and knot it. Slide the needle inside the folded hem allowance and bring it out at the fold, so the knot is hidden between the layers. Never knot on the outside, because it will show through.
- 04
Catch one or two fibres of the outer fabric
Directly below where the thread came out, slide the needle into the outer fabric and pick up just one or two fibres, a bite of about 1 mm. Do not go through to the right side. This tiny catch is what holds the hem while staying invisible.
- 05
Take a diagonal stitch inside the hem
Move 6 to 8 mm along the fold and take the needle back into the hem allowance, angling it so the stitch runs diagonally. Pull the thread gently until the hem sits flat against the fabric with no ridge and no slack. The stitch should be snug rather than tight.
- 06
Work across at an even rate
Continue picking up one or two fibres of the outer fabric and slipping back into the fold, keeping the spacing even at 6 to 8 mm. Every few stitches, turn the work over and check the right side is clean. If you can see dots of thread, you are catching too much fabric.
- 07
Finish and press
At the end, run the needle inside the hem allowance, make two tiny stitches to lock it, and trim. Press the hem from the wrong side over a towel so the stitches sink into the cloth. Let it cool before moving it, because a warm hem can still take a set.
What the stitch is actually doing: a floating thread, not a seam
A blind hem is not a seam in the ordinary sense. Nothing is joined edge to edge, and no two raw edges are held together. The hem allowance is folded and pressed into a stable double thickness, and the thread's only job is to stop that pressed fold from dropping. Between the catches the thread floats diagonally inside the hem allowance, held at each end but free in the middle, which is why the 6 to 8 mm spacing in the step-by-step matters so much: it is the length of unsupported thread that has to absorb every bend and stretch the garment sees.
The diagonal direction of the stitch is not decoration either. A stitch that runs diagonally across the weave spreads its pull across more than one thread line, and it leaves a little loop length in reserve, so when you sit down or bend and the fabric stretches a fraction, the loop gives instead of snapping. A straight, vertical stitch pulls on a single line of weave and shows up on the right side as a row of small dimples, even when the catch itself was tiny.
Because each loop is independent, the spacing is also a form of insurance. If one catch wears through or is missed, the neighbouring stitches at 6 to 8 mm either side carry the hem and nothing unravels into a dropped hem. That redundancy is the reason a hand blind hem can be repaired in a small section instead of being taken out and re-sewn from scratch.
Finally, keep in mind what the 1 mm bite is doing structurally. You are not sewing through the outer fabric, you are borrowing a few surface fibres from it. The needle enters and leaves on the wrong side, so no part of the thread ever crosses the face of the cloth. Get the bite right and the outer layer keeps its full strength and its clean surface; get greedy and you poke a visible hole in it.
When it goes wrong: reading the right side
Dimples are the most common fault. They appear as small dents in the outer fabric directly above each catch, and they mean either that you picked up more than one or two fibres, or that you pulled hard after taking the catch. The two have different fixes. If the fabric is only lightly marked, run the point of the needle under the dimple to lift the fibres and steam it; many dents fall out. If the mark survives a pressing, the thread has pulled a whole yarn out of line and the section has to be re-sewn with a shallower bite.
Visible dots of thread on the right side are the same fault caught earlier, which is exactly why the step-by-step tells you to turn the work over every few stitches. Do that check under a good light, at eye level, not from above. A dotted line reading across the hem means the bites are too deep; a faint shadow along the hem usually means the thread was drawn too tight and the fold is lifting, rather than too much fabric being caught.
A hem that has dropped in one patch, rather than all the way round, almost always has skipped catches in it. This happens when you speed up: the needle goes down into the outer fabric and back into the fold without ever actually coming up with a fibre on it. Test by pulling the hem gently downwards every 10 cm or so as you work. If a section gives, re-sew just that span from the wrong side at the same 6 to 8 mm spacing instead of unpicking the whole hem.
Knots and tails show through much more than people expect, especially on light cloth and on any fabric with a sheen. A knot sitting inside the fold presses against the face of the fabric and reads as a lump from the outside, and a long tail left dangling inside the allowance can work its way out through the fold edge after a few wears. Anchor inside the fold as the third step describes, and run every finished tail back inside the allowance before trimming.
Thread, needle, and how a substitution changes the finish
The 40 cm thread length is a working length, not a limit set by the hem. A thread much longer than that drags along the fabric with every stitch, abrades, kinks and knots, and by the end of a run it has lost its body and gone fuzzy, which is exactly when stitches start to look untidy. A 40 cm thread will not carry you all the way round a skirt hem, so expect to rethread a couple of times across one hem, and rethread before the thread starts to fray rather than after.
Thread fibre is the substitution that changes the result most over time. On wool and wool-blend trousers, a silk or cotton-wrapped thread has a little give and presses into the wool surface, so the catches sink into the cloth instead of standing proud. A polyester thread is stronger than the wool fibre it is stitched into, and over years of wear it can saw against the yarn it holds. On poly-viscose and on cotton and curtain fabrics the same polyester thread is perfectly durable and much easier to source in an exact colour, so it is a reasonable choice there.
On colour, the tips are right that a slightly darker thread disappears better than an exact match, and the reason is worth knowing. On the right side the eye is reading contrast, not colour: a thread a shade darker than the fabric reads as shadow along the hem, while an exact match on a fabric with any sheen reflects light differently from the cloth and can actually shimmer slightly. On very dark navy or black, going lighter is the mistake, because a lighter thread reads as a highlight against the dark ground.
Needle choice is where beginners lose control. A sharps in size 9 to 10 is correct for the fine and medium wovens in the materials list, but the longer needle in that size swings as you push it through a dense fabric, and a swinging needle takes a 2 mm bite instead of a 1 mm one. If your catches keep coming out too deep, try a shorter needle in the same fine size; the short shaft gives you direct control of the tip, which is what a 1 mm bite actually requires. A fine needle also makes a smaller hole, and on tightly woven wool that hole closes as soon as the thread passes through.
Variations: three ways to change the look or the difficulty
The catch stitch, also called herringbone, is the same idea built with a crossing action: each stitch slants back across the previous one, which gives the row a small amount of built-in stretch. On knits, jerseys and anything that has to move with the body it is a better choice than the blind hem, because a 1 mm catch in a knit grabs a loop of yarn rather than a stable woven thread and will eventually tear it. Save the blind hem for the stable wovens in the materials list and use the catch stitch when the fabric has give.
A slip stitch produces a flatter and slightly tighter finish, with the needle coming out along the fold and going back in just above it. It looks neater from the inside and holds a narrow hem more securely, but the catch sits closer to the fold edge, so on anything but a fine fabric the stitch can read as a faint line from the right side. If your hem allowance is on the narrow side, under the 3 cm used for a skirt, a slip stitch is often the more reliable route than a blind hem.
A machine blind hem is the fast option and it uses the same principle: the blind hem foot folds the fabric into a stepped shape and the needle takes one zigzag bite into the fold. For curtains, which are long, straight and heavy, it saves a great deal of time and the small dots it leaves on the right side are lost in the drape. On wool trousers or a satin skirt those dots are visible, and that is the case the hand version exists for. A hand-sewn skirt hem takes about 25 minutes and gives a finish the machine cannot match on those fabrics.
If you want a beginner-level shortcut, fusible hem tape will hold a pressed-up hem with no stitching at all, but it changes the garment permanently: the hem goes stiff, the drape is lost, and the bond fails after a limited number of washes. It is a sensible fix for a hem that is already the right length and has simply come down, and a poor choice for trousers or a skirt you are making properly, where the softness of a hand catch is the whole point.
Finishing and care so the hem lasts
Locking off properly is what keeps the hem from coming down at the end of the row. The two tiny stitches described in the final step keep the last catch from pulling through, and running the needle back inside the allowance first hides them. Do not backstitch and do not tie a knot: a backstitch makes a dense lump that presses against the face of the fabric and can be seen from the right side, and a knot can work its way through a fine cloth over time. Trim close, then bury the tail inside the allowance.
Pressing is the last stage of the sewing, not a tidy-up afterwards. Press on the wrong side over a towel, with steam, and then leave the hem completely alone until it is cold. Wool and wool blends take their set as they cool, so a hem moved while still warm will hang in soft waves and no amount of later pressing will pull it back neatly. Never press the right side directly: on wool you will glaze the surface, and even on cotton you risk pressing the fold line in as a permanent crease mark across the face.
Washing habits decide how long the hem survives. Turn trousers and skirts inside out before washing so the face of the cloth is not abraded against the drum, and hang trousers from the waistband rather than over the hem, because a hem carrying the weight of wet wool will stretch and pull the catches. If the fabric is cotton and will be washed often, steam the hem allowance before you sew so it shrinks first; a hem that shrinks after the garment is finished drags the outer layer down with it and makes every catch visible.
Repairs are quick when you need them. Because the catches are independent and spaced at 6 to 8 mm, a single broken stitch does not release the hem. Re-sew that one span from the wrong side at the same spacing and press it, rather than unpicking the whole hem, and press the fold line again after each wash so the original crease stays crisp and the stitches stay buried in the cloth.
Frequently asked questions
- Can I sew a blind hem on a sewing machine instead of by hand?
- Yes, with a blind hem foot, which folds the fabric into a stepped shape so the needle takes a single zigzag bite into the fold. It is much faster, which makes it the sensible choice for curtains, where the hem is long, straight and heavy. The trade-off is that the machine leaves a small dot of thread on the right side at every bite, and on wool trousers or a satin skirt those dots are visible. The hand version takes about 25 minutes for a skirt hem and stays truly invisible on those fabrics, which is why it is still worth doing by hand.
- My stitches are showing on the right side. What went wrong?
- You almost certainly picked up more than one or two fibres of the outer fabric. Work only from the wrong side, and unpick just the span that shows: slide a seam ripper under a loop from the wrong side every few stitches and cut, rather than cutting the fabric. Then re-sew that section with a 1 mm bite. Before you start again, practise the bite on a scrap of the same fabric to feel how shallow it has to be, and check the thread colour while you are at it, since a slightly darker thread reads as shadow instead of a visible line.
- Why does my hand blind hem pucker or leave a ridge?
- The thread is being pulled tighter than it needs to be. The correct tension is snug: the hem sits flat against the fabric with no ridge and no slack. Release the thread after every stitch rather than pulling at the end of a run, because tension added at the end travels back through the whole row. Small puckering usually steams out when you press on the wrong side over a towel. If a ridge still shows along the fold after pressing, the hem allowance is too bulky at the fold line, so trim it and re-sew.
- Will a blind hem stitch work on knits or stretchy fabric?
- Not well. The 1 mm catch grips individual woven yarns, and on a knit a catch grabs a loop that moves and eventually tears, so the hem comes down. Use a catch stitch, also called herringbone, on knits and jerseys, since its crossing stitches have built-in stretch, or use a twin needle. Keep the hand blind hem for the stable wovens in the materials list: wool, cotton and poly-viscose trouser and skirt fabric, and curtain cloth.