How to Sew a Button Back on a Suit Jacket or Trousers

Suit buttons come loose sooner or later, usually at the worst moment. Sewing one back on takes about ten minutes, and done properly it will outlast the original. The difference between a repair that looks homemade and one that looks factory-fresh comes down to three things: the right thread, copying the original pattern and building a proper thread shank. Here is how to do it on a jacket front, a sleeve and a pair of trousers, and when a tailor is the better choice.

What thread should you use for a suit button?

Use strong thread, doubled. Ordinary all-purpose polyester thread works when doubled, and heavy-duty or button thread is better still. Tailors traditionally use linen thread for trouser buttons, which take the most strain. Avoid thin cotton thread, which wears through quickly where it rubs against the buttonhole.

Match the thread to the other buttons on the garment, not to the fabric. On most suits that means thread in the color of the button. Running the thread through a block of beeswax before you start makes it smoother and less likely to tangle or knot as you sew.

Before you start: read the other buttons

The best guide to sewing a button on a suit is the button next to it. Before you thread the needle, look closely at a matching button that is still attached and note three things: the stitch pattern, the thread color and the height of the shank between the button and the fabric. Then look at the spot where the lost button was. You will usually see small holes or thread ends marking the exact position. Pull out any loose thread so you start clean.

If the button is lost, look for spares. Many suits come with spare buttons, sewn inside the jacket or trousers or supplied in a small bag. If there are none, our guide to suit buttons explained covers sizes and materials, so you can match the set.

How do you sew a button back on a suit jacket?

How long should a button shank be?

The shank should be about as long as the buttonhole edge is thick, so that when the button is fastened the layer with the buttonhole sits flat underneath it. On most suit jackets that is a few millimeters, which is roughly the slack a toothpick or matchstick gives you. Thick overcoats need a longer shank.

A shank that is too short makes the button strain against the fabric, pulls the front edge into a pucker and wears through the thread. A shank that is too long lets the button flop forward. If in doubt, look at the shank on a matching button and copy it.

Which pattern should you use on a four-hole button?

Men's tailoring traditionally uses four-hole buttons, sewn in one of a few patterns. Always copy the pattern already on the garment, so every button matches.

How do you sew a button on suit trousers?

Trouser buttons take more strain than any others on a suit, especially the waistband button, which carries the pull of the waist every time you sit. Sew them with heavy-duty or linen thread, doubled, and give them only a short shank, because the waistband tab that fastens over them is thin. Many suit trousers fasten at the front with a metal hook and bar plus a button on an inside tab; both are sewn the same careful way.

Brace buttons and back pocket buttons follow the same method. For brace buttons inside the waistband, catch only the inner layers if you can, so no stitches show on the outside. A loose hook or bar is sewn through each of its holes with several tight stitches of the same doubled thread. If you are adding brace buttons for the first time, our guide to belt loops, side adjusters and braces explains where they go.

How do you sew sleeve buttons and metal buttons?

On a non-working cuff, the sleeve buttons are decoration and never pass through a buttonhole, so sew them almost flat, through the closed vent. Keep the same spacing as the others: if they touch or overlap, line the replacement up with its neighbors before you anchor it.

On a working cuff, take care. The buttons sit on the underlap, the lower layer of the sleeve vent, and the buttonholes are cut in the layer on top. Open the vent and sew only through the underlap, or you will stitch the cuff shut. Give each button a short shank so it passes through its buttonhole easily.

Metal blazer buttons usually have a shank built in, a small loop on the back. Sew through the loop four to six times, with the loop lying in the same direction as the buttonhole so the button does not twist when fastened. No thread shank is needed.

Why do suit buttons keep coming loose?

Most factory buttons are sewn by machine, and some machines use a chain stitch that can unravel along its length once a single thread breaks. Thread also wears where it rubs against the buttonhole, and a button sewn flat with no shank wears faster because it strains every time you fasten it. A jacket that is tight across the front puts extra pull on its fastening button, which is a fit problem as much as a sewing one.

Undoing the right buttons at the right moment saves wear too: our guide to which buttons to fasten covers every jacket style.

When should you take it to a tailor instead?

Sewing on a button is a fair job for anyone. Take the garment to a tailor instead in these cases.

• The button tore out fabric or left a hole. The area needs reinforcing from behind before a button will hold.
• A buttonhole is frayed or torn. Buttonholes are reworked by hand or machine, which takes skill and the right thread.
• You are replacing a full set, for example upgrading plastic to horn. A tailor will match the pattern and shank height on every button.
• The suit is bespoke or expensive and you want a repair nobody can spot.
• The hook and bar or the fly has torn away from the waistband or front.

As of 2026, most tailors charge about $2 to $5 per button to sew one on, plus the cost of any new buttons. That is a small price on a good suit, and our guide to suit alteration costs lists other common jobs. For the everyday habits that keep buttons and fabric in good shape, see how to care for a suit.

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