A white T-shirt is the hardest piece of clothing to get right, because there is nowhere to hide. No print, no pattern, no dark colour to blur a bad shoulder line. Everything shows: the seam, the drape, whether the cotton is thick enough to be opaque. Most beginners shop for one the way they shop for everything else — grab the usual size, hope for the best — then wonder why one plain tee looks sharp and another looks like something they slept in. The difference is fit, and fit comes down to a short list of measurements you can check in a fitting room in about a minute. Here are the ten mistakes that trip people up most, and how to fix each one.
Shoulder Seams: Check This Line Before Anything Else
Mistake 1: Letting the seam hang off your shoulder. The shoulder seam should sit right at the edge of your shoulder bone, where the flat top of your shoulder starts to curve down into the arm. If the seam lands an inch down your upper arm, the shirt is too wide through the chest, and you will see fabric pooling under the arms and bunching when you raise a hand. If the seam sits inside the curve, the shirt is too narrow and will pull tight across the chest.
Mistake 2: Buying for the body and ignoring the shoulders. Almost everything else on a tee can be adjusted, but shoulder width is the hardest and most expensive thing for a tailor to change. Necklines are nearly as difficult. So treat those two as non-negotiable and treat the rest as negotiable.
Buy for the shoulder and the collar. Adjust the length, the sleeve and the waist afterward.
If you are between sizes and the shoulder fits, take the larger one and have the body slimmed. If the shoulder does not fit, put it back on the rail — no amount of styling will fix it.
Sleeve Length and Width: Where the Hem Lands Matters
Mistake 3: Sleeves that stop at the widest part of your arm. A sleeve hem that ends mid-bicep visually cuts the arm at its thickest point, which makes the whole arm read shorter. Aim for a hem that finishes just above or at the mid-bicep with a clean horizontal line, and check it with your arms relaxed, not flexed.
Mistake 4: Sleeves that grip or balloon. Pinch the sleeve hem between finger and thumb. You want roughly an inch of slack, maybe two, so the fabric hangs rather than wraps. Too tight and you get a sausage effect plus visible stretch marks in the weave; too loose and the sleeve flares like a bell and swallows your forearm when you reach for something. If you like a rolled cuff, roll once or twice at most — a fat triple roll adds bulk right where you do not want it.
Fabric Weight and Opacity: Read the Cloth, Not the Size Tag
Mistake 5: Buying cotton so thin it is see-through. Hold the shirt up to a window or a shop light. If you can clearly read the outline of your hand through a single layer, it will show everything under it in daylight. Lightweight cottons drape softly but cling, and they tend to lose shape at the collar and hem within a few washes.
Mistake 6: Assuming heavier always means better. Heavy cotton holds its shape and stays opaque, but past a certain point it feels stiff and hot, and it stands away from the body instead of following it. A midweight cotton is the useful everyday choice for most people: substantial enough to be opaque, soft enough to drape, and comfortable indoors.
Three checks worth doing in the shop
- Stretch it and let go. Fabric that springs back cleanly will keep its shape. Fabric that stays baggy at the elbows and knees will look tired by lunchtime.
- Look at the collar. A ribbed collar with its own seam holds better than a thin band of self-fabric, which tends to ripple after a few washes.
- Check the side seams. Give the shirt a gentle tug sideways. If the stitches look strained or the fabric dimples along the seam, the fit is too tight.
Necklines: Crew, V, and the Collar That Gives Up
Mistake 7: A crew neck that sits too low or too wide. On a good crew, the collar edge sits close to the collarbone and roughly a finger's width from the base of your neck. When it slips wider, you get a sagging oval that exposes the collarbone and reads as underwear rather than a shirt.
Mistake 8: A V-neck cut too deep. The point of the V should land a few inches below the collarbone — visible, but not halfway down the chest. Deeper than that and it stops working as a layering piece and starts looking like a costume. Match the width of the V to your face, too: a narrow V flatters a rounder face, a wider one balances a longer face.
Body Width, Length, and the Tuck
Mistake 9: Ignoring the armhole. A low armhole is the hidden cause of most tee discomfort. Raise both arms overhead and look in the mirror. If the whole shirt lifts up like a curtain or you feel fabric dragging under the arms, the armhole is too deep and the shirt will never sit flat.
Mistake 10: Getting the hem length wrong. For a modern untucked look, the hem should land between the top of your waistband and the middle of your fly — no lower. Any longer and the shirt looks like a tunic over trousers, and the extra fabric bunches at the hips. If you plan to tuck, you want a couple of inches of extra length so the shirt stays put when you move, rather than a long tail that balloons out of the waistband.
One more thing beginners overlook: shrinkage. Pure cotton can lose a few percent of its length and width in a hot wash and a hot dryer. If a shirt fits perfectly but just barely, size up or plan to wash it cool and dry it on low. Wash white tees with whites, keep the heat down, and hang or lay them flat to dry — ribbed collars especially hate high heat.
A Fitting Routine You Can Run in a Minute
Take two or three sizes of the same tee into the fitting room with you and work in this order. The first one that passes all five checks is the one you buy.
- Shoulder seam sits on the edge of the shoulder bone.
- Collar hugs the collarbone without gaping or riding low.
- Side seams fall roughly straight down, without pulling or billowing.
- Sleeve hem ends near the mid-bicep with an inch of slack.
- The fabric is opaque in daylight and springs back when stretched.
White T-shirts are unforgiving, which is exactly why they are worth getting right. Once you know your shoulder width, your ideal sleeve hem and your preferred fabric weight, buying basics stops being a gamble. Note those three numbers on your phone, and every white tee you pick up afterward will either fit or go straight back on the rail.
Photo: PNNTRN / Pixabay