How Should a Suit Fit? A Simple Checklist

A suit fits when the shoulder seams end at the edge of your shoulders, the jacket buttons without an X-shaped pull, the jacket covers your seat, about 1 to 1.5 cm of shirt cuff shows below the sleeve, the collar sits against your shirt collar, the trousers sit at your waist without a belt, and the hem just touches your shoes. Shoulders are the one thing a tailor can't fix, so buy for the shoulders.

Wendy WeiSeptember 14, 2026 · 3 min read

1. Shoulders

The shoulder seam should end at the edge of your shoulder bone. If it hangs past, the jacket's too big; if your shoulder pushes out past it, or there's a dent in the sleeve below, it's too small. This is the hardest fit to alter, so buy for the shoulders and tailor the rest.

2. Chest and Buttoning

Button the jacket. It should lie flat. An X-shaped pull around the button means it's too tight; a lot of loose fabric means too big. You should be able to slide a flat hand under the lapel.

3. Jacket Length

A classic jacket covers the seat of your trousers. Modern cuts run a little shorter, but if it doesn't cover most of your seat it's too short, and a long one shortens your legs. With your arms at your sides, the hem usually falls around your knuckles.

4. Sleeves

About 1 to 1.5 cm (a quarter to half an inch) of shirt cuff should show below the jacket sleeve with your arms at your sides. Sleeves are easy to shorten or lengthen.

Read more: Smart Casual for Men, Explained

5. Collar

The jacket collar should rest against your shirt collar without a gap at the back of the neck. A gap, or a bulge of fabric below the collar, is a sign the jacket doesn't fit your posture.

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6. Button Position

On a two-button jacket, the top button should sit at or just above your navel. Too low and the jacket looks sloppy; too high and it looks tight. Leave the bottom button undone.

7. Trouser Waist and Seat

Trousers should stay up without a belt and sit at your waist without pinching. The seat should be smooth, not pulling or baggy.

8. Trouser Length and Break

The 'break' is the fold where the trouser meets the shoe. A slight break, or none, looks modern; a full break looks traditional and can make trousers look too long. The hem should at least touch the top of your shoe. Taper the leg slightly so it doesn't flare over the shoe.

What a Tailor Can and Can't Fix

Easy and cheap: sleeve length, trouser hem, taking in the waist and the jacket's sides. Possible: tapering trouser legs, adjusting the seat. Hard or impossible: shoulders, jacket length and chest that's too small. A tailor can turn a decent off-the-rack suit into one that looks made for you.

To check how a style looks on your build, try it on a model of your height and body type in Ollie Stylist. See also smart casual for men.

Frequently Asked Questions

How should a suit jacket fit?

Shoulder seams at the edge of your shoulders, no X-shaped pull when buttoned, long enough to cover your seat, with 1 to 1.5 cm of shirt cuff showing.

How should suit trousers fit?

Staying up without a belt, smooth at the seat, with the hem touching your shoe with a slight break or none.

What can't a tailor fix on a suit?

Shoulders are the hardest, along with a jacket that's too short or too small in the chest. Buy for the shoulders.