Short answer: a dress shirt fits when the shoulder seam sits at the edge of your shoulder, you can fit two fingers inside the buttoned collar, the cuff ends at your wrist bone, there's no pulling at the chest buttons, and there's roughly two to three inches of loose fabric at your waist. If those five are right, the shirt fits regardless of what the label says.

The five checkpoints

1. Shoulder seam

The seam joining the sleeve to the body should land right where your shoulder ends and your arm begins. Inside that point, the shirt is too small and will pull across your back. Beyond it, the sleeve head droops and the whole shirt looks borrowed.

This is the most important checkpoint because it's the one a tailor can't fix. Everything else on this list can be altered.

2. Collar

Button it fully. You should be able to slide two fingers flat between the collar and your neck — comfortable but not loose. One finger means it'll be uncomfortable by mid-morning and will look tight under a tie. Three or more means the collar will sag away from your neck and look sloppy under a jacket.

Separately: check that the collar has structure. A collar that collapses is the most common reason a shirt "stops looking right" without an obvious cause, and it's what goes first on a shirt that's been washed a lot.

3. Chest and the button test

Button the shirt and stand normally. Look at the placket between the third and fourth buttons — the widest point across your chest. There should be no horizontal pulling and no gap.

Then sit down and cross your arms. This is where most shirts fail, and it's the version of the test that matters, because you spend your day sitting, not standing in a mirror.

4. Sleeve and cuff

With your arms at your sides, the cuff should end at your wrist bone — where your hand begins. Buttoned, the cuff should be snug enough that you can't slide it over your hand without unbuttoning it.

Under a jacket, about half an inch of shirt cuff should show. If yours doesn't, the sleeve is short.

5. Waist and length

Pinch the fabric at your waist. Two to three inches of loose fabric on each side is the target for a fitted shirt. Less and it pulls when you sit; more and it billows over your waistband when tucked.

For length: tucked, the shirt should stay tucked when you raise both arms above your head. Untucked, the hem should sit around the middle of your fly — anything longer needs to be tucked.

Slim, athletic or classic

These are cuts, not sizes, and picking the right one solves more problems than changing size does.

The quickest self-test: if your shirts pull at the chest but are loose at the waist, you want athletic. If they fit at the chest and billow badly at the waist, you want slim or athletic depending on your shoulders. If they're tight everywhere, you want a larger size in the same cut.

Athletic builds in detail: Dress Shirts for Big and Athletic Guys.

When to consider tall

Tall adds sleeve and body length without adding width. Reach for it if you're over roughly 6'2", if your cuffs sit above your wrist bone, or if the shirt untucks when you raise your arms — going up a regular size makes you wider, not longer, so it doesn't solve either.

What a tailor can and can't fix

Which gives a simple buying rule: buy for your shoulders, chest and neck, then alter the rest.

Common questions

How should a dress shirt fit at the shoulders?

The shoulder seam should sit exactly where your shoulder ends and your arm begins. This is the one measurement a tailor can't correct, so it should drive your size choice.

How tight should a dress shirt collar be?

You should be able to slide two fingers flat between the buttoned collar and your neck. One finger is too tight, three is too loose.

Where should dress shirt sleeves end?

At the wrist bone, where your hand begins, with your arms at your sides. Under a jacket, about half an inch of cuff should show.

How much room should a dress shirt have at the waist?

About two to three inches of loose fabric pinched at each side. Less pulls when you sit; more billows over the waistband when tucked.

What's the difference between slim fit and athletic fit?

Slim is narrow through the chest and waist, for lean frames. Athletic is full through the chest and shoulders but still tapered at the waist, for V-shaped builds. They're different cuts, not different sizes.

Should a dress shirt be tucked in?

With dress pants, yes. Untucked works if the hem sits around mid-fly; a shirt long enough to cover your back pockets is designed to be tucked.

What we make

&Collar shirts come in slim and athletic fits, sizes XS–5XL, with tall sizing. The four-way stretch fabric means a closer cut doesn't cost you movement, and the collar is built with two layers to keep its structure through repeated washing.

Measurements by size are on our size guides. Shirts are $49.99 or any three for $99. Returns are 45 days from the day your order arrives, so trying a fit costs you nothing but the trip to the mailbox.