Secondhand clothing rarely fits perfectly, and the reason is structural rather than unlucky. A garment was cut for one body, worn by that body, and then washed and dried in ways that changed its measurements. When it reaches you, adjusting it is normal rather than a sign that you picked wrong. What matters is knowing which alterations are routine and which ones amount to remaking the garment.
The honest rule is that you should buy for the parts that are hardest to change and adjust the rest. Those parts are the shoulders, the chest or bust, and the rise on trousers. Everything below and around them is negotiable.
The easy end: hems, seams and small take-ins
These are the alterations that a competent home sewer can do in an evening, and a tailor will do cheaply.
- Shortening a hem. Trousers, skirts and dresses are the simplest case, because the hem is a straight or gently curved line near the bottom where the fit is least critical. Shortening is easier than lengthening, because you can always remove fabric.
- Shortening sleeves. Almost as straightforward, though a sleeve with a cuff and a placket adds work, and a shirt sleeve is cut on a taper that can look odd if too much comes off.
- Taking in side seams. Narrowing a garment at the sides is the standard route to a closer fit. It is reversible, and the seams are usually accessible.
- Adding darts. Darts are the wedge-shaped tucks that shape fabric to the body. Adding a pair at the back waist, or at the bust, converts a garment cut for a straighter figure into one that follows yours.
- Replacing buttons and adjusting simple fastenings. Cosmetic and quick, and often the only thing a garment needs.
The common thread is that these alterations work on the outer edge or the lower part of the garment, where the shape is forgiving and the fabric has room to move.
The middle: waistbands, linings and anything with a matching problem
A step up in difficulty, these are still worth doing on a garment you love but are worth pricing before you commit.
- Taking in a waistband through the centre back seam. Effective and tidy if the waistband has a seam there, awkward if it does not, because the band has to be opened, shortened and reattached without twisting.
- Hemming a lined garment. The outer shell and the lining have to be shortened to different lengths so the lining hangs slightly loose, following the shape of the garment. Get it wrong and the lining pulls the outer fabric out of shape.
- Shortening a garment with a vent, a slit or a kick pleat at the back. Removing length near the vent can change where the opening sits and how the garment moves when you walk.
- Taking in a striped or checked garment. Every seam you move breaks the pattern match unless you work carefully, and a broken match is more visible on a fitted garment than on a loose one.
The hard end: shoulders, rise and letting out
These alterations require re-cutting, pattern knowledge or a specialist, and they frequently cost more than the garment is worth.
- Changing the shoulder width. The shoulder line and the armhole, the curve where the sleeve joins the body, are the most complex three-dimensional parts of a garment. Moving the shoulder inward or outward means reshaping the armhole, which changes the sleeve, which changes how the whole thing hangs. This is the classic case for walking away.
- Altering the crotch rise on trousers. The rise and the seat are built as a unit, and changing one affects the other. A tailor can do it, but the result is unpredictable even in skilled hands.
- Letting a garment out. This only works if the seam allowances are still there. Many ready-made garments are trimmed close after stitching, so there is simply nothing to release. Check the inside of the side seams before you plan on it.
- Lengthening. You can only lengthen by whatever hem allowance the original maker left, which is often narrow, and the old fold line usually remains visible as a faint crease after the fabric has been let down.
- Narrowing the whole garment dramatically or re-cutting a collar. Both come close to remaking the piece, and the cost reflects it.
How to spot a garment that has already been altered
Secondhand clothing has often been adjusted once already, which limits what you can do next and can explain why something fits strangely. Look for these traces.
- Old needle holes. Unpicking leaves a line of tiny holes along the former stitch line, most visible on closely woven and coated fabrics.
- A crease where a fold used to be. Let-down hems and let-out seams keep a shadow of the old turn.
- Extra stitching lines inside. Compare the stitch density and thread colour; original stitching is usually uniform, later work tends to be different in colour or spacing.
- Darts that no longer have a purpose. Unpicked darts often leave a faint pressed shape, and the garment may have been shaped twice.
- Serged edges where the original was a flat-felled seam. This indicates that the seam has been opened and re-finished.
- Buttons or buttonholes that do not match. A replaced row of buttons is common, and it hints at the garment’s history.
- A hem that is shorter than the original and shows a machine line where the old hand-finishing was.
How alterations change the way fabric hangs
Fabric behaves differently depending on how much of it there is and where the shape is. Taking in the sides of a garment designed to be loose does not simply create a smaller version of the same thing; it changes the drape, because the fabric that used to fall from the shoulder now pulls from a narrower point.
Shortening changes proportion. A coat that loses too much length stops looking like a coat and starts looking like a jacket that was cut down. A dress shortened to the knee can lose the line the fabric was chosen for. Over-fitting does the same thing from the other direction: pull a boxy shape tight to the body and the fabric will pucker and strain at every seam.
If you are considering a major alteration, put the garment on and pin or clip the change before you commit. Look at how the fabric falls when you move, not just when you stand still.
When to leave it on the rack
Refuse the garment when the shoulders are wrong, when it is too small in more than one place, or when any change would require re-cutting the armhole or the collar. Refuse anything with a fused front and a fitted shape, because the glued interfacing cannot be re-pressed after major work. And refuse anything where the alteration quote is more than the garment is worth to you.
Buy for the shoulder and the chest, adjust the length and the waist, and let the rest go. That single habit removes most of the disappointing alterations from your life before they happen.