How a Suit Should Fit: 12 Points to Check in the Mirror

How should a suit fit? It is the most-asked question in tailoring and the hardest to answer in words, because fit is felt at a dozen small places and described in none. This is the version you can run yourself: twelve points to check in a mirror — two minutes, no tailor required — followed by the honest dividing line between what an alteration can fix and what only remaking fixes. Because here is the uncomfortable arithmetic: most off-the-rack suits, and even many made-to-measure ones, fail three or four of these twelve, and every failure quietly shrinks the number of occasions the suit earns.

## Fit is made in three places

Ninety percent of what reads as “that suit looks right” comes from three intersections. The shoulder line, where the sleeve meets the jacket at the exact point your arm leaves your body. The chest and armhole, where the canvas cups you and the height of the armhole decides how far you can lift a hand without dragging the whole jacket with it. And the trouser seat, where the side seams must drape downward without pulling a diagonal wrinkle. A jacket missing any of the three reads “borrowed” no matter how good the cloth is.

## The twelve mirror checks

Stand a full body-length from a mirror and run all twelve; none cancels another.

- 1. Collar gap. The jacket's back collar should sit against your shirt collar. If a gap shows between them, the shoulders were cut too wide — tailors run this check first, because everything else hangs from it.
- 2. Shoulder line. The shoulder seam should end where your shoulder ends, not travel down the arm. Its edge should sit flat, not puff into a small horn.
- 3. Armscye range. Raise your arm to horizontal. On a properly cut armhole, the collar stays seated and the jacket lifts only slightly — not a full shrug that hoists the whole buttoned front.
- 4. Chest drape. Below the armhole the chest should cup forward, the cloth following your torso's curve, not hugging it flat. A chest that tents outward and never returns, or one that shows pull-lines in both directions, is a pattern problem.
- 5. Sleeve length. The cuff should end at the top of the wrist bone — enough to show 1–1.5 cm of shirt cuff when your arm hangs naturally. A sleeve hiding the whole shirt cuff is usually also hiding a clumsy shoulder.
- 6. Button-pull X. Button the front. If an “X” of tension wrinkles runs from each buttonhole toward its button, the stance is fighting your torso. A faint X across the stomach at the lowest button is the clearest single sign the jacket is small in the waist or short in the body.
- 7. Sleeve pitch. Look at the sleeve from the elbow down: it should hang along your arm's natural angle. A seam twisted toward thumb or little finger means the armhole was rotated on the pattern — and rotation rarely survives alteration.
- 8. Jacket length. With your hand flat over your palm behind you, the jacket should cover roughly that much of the seat — enough to cover the seat, not reach mid-thigh. Longer reads heavier; shorter reads sharper until it reads like a shirt.
- 9. Trouser side drape. The side seams should run straight and clean to the shoe, without forward or backward billow. A hip pocket that catches and drags its seam means the hip was cut narrow for your shape.
- 10. Trouser seat. From behind, the seat should be smooth. Two diagonal upward wrinkles from each cheek meeting at the centre mean the seat is cut tight; a hanging fold of cloth under each cheek is the loose version — both pull the seams out of shape over months.
- 11. Trouser break. At the shoe: no break just clears the laces and shows a clean cuff line; quarter break folds once and is the safe default; full break folds twice and belongs to the heavier, wider classic. Whatever your taste, the trouser should touch the shoe — never a gap above the sock.
- 12. Rise and the seated test. Sit down. If the trouser knee climbs and the waistband needs a tug to stay where you placed it, the rise is cut short. Good rise: comfortable seated, and standing without bagging at the crotch.

A jacket can fail several of these at once — though check 1 and check 6 are the two where repairs rarely help, because each is a cut error, not a wear symptom.

## What alteration can fix, and what only remaking can fix

Here we owe every reader honesty instead of a sales pitch:

- Alterations genuinely fix: sleeve and trouser lengths, waist take-in or let-out within about one size either way, tapering the leg, shortening a jacket as far as the internal balance allows, cuff widths, button stance moves, replacing a worn lining.
- Alterations cannot fix: the shoulder line, the armhole placement, or a seat error more than a size out. Re-cutting a shoulder means undoing the sleeve, collar, padding and armhole — which rebalances everything above it; a “cheap shoulder fix” ends with a worsened collar gap. Recovering any of these means drafting again — made new, not made shorter.

The practical ordering, then: buy or commission by the three structural points — shoulder, chest/armhole, seat — and let an alterations list settle lengths and waists afterwards. Structure is exactly what off-the-rack cannot solve.

## Fit differences by occasion

The twelve checks stay constant; the aimed silhouette moves with the room. Business suits keep a faint, calm drape — no overtightening at the waist, because Bangkok wear means hours seated in traffic and then in an 18°C boardroom. Black tie runs a touch cleaner: a slightly closed chest, a button stance drawn a little higher, trousers with no break reading as part of the evening line. Linen and casual suits accept more ease — linen creases, and a linen jacket fought into a business-tight fit looks tired within the hour; give linen half a breath of air.

## Frequently asked

Can a badly fitting suit be fixed? — Lengths and waists, almost always. Shoulders, armholes and seats only by re-cutting — which is remaking territory. Score the twelve checks first: if your list is lengths and waist alone, one alteration visit is inexpensive and worth it; if the collar gap stays open after re-buttoning over the shirt you normally wear, that suit was never your size.

How much room should a jacket have? — Enough that a flattish hand slides under the buttoned front without the button area pulling into an X — a closed fist is too much, nothing is too little. Modern cutting runs closer to the body than 1990s cutting did, but “close” means the cloth follows your curve, not that a seam fights your torso.

Bring any suit you are unsure about to an atelier and ask them to score it against a list like this before any alteration money is spent. At ours the assessment is free and takes about 15 minutes — book a sitting — and when the fix is worth doing rather than remaking, the alterations service starts from ฿800 with your pattern on file.