A white t-shirt is the most useful thing in a wardrobe until you catch it in daylight and can see straight through it. Whether a white tee is opaque is decided by a few things you can check before you buy: the weight, the knit, the cotton and the fit.
Choose a white t-shirt of at least 180 GSM, in a tightly knitted jersey or a double knit such as interlock, made from long-staple cotton. Make sure it is not too tight across the chest, and wear a skin-tone vest, not a white one, if you want it fully opaque.
Why white t-shirts turn see-through
- Low weight. Below about 150 GSM there is simply not enough yarn to block light.
- A loose knit. Gaps between stitches let light through, especially when the fabric is stretched.
- Stretch. A tee that is tight across the chest or shoulders pulls the knit open.
- Wear. Cheap cotton thins as loose fibres wash out, so a tee gets more see-through with age.
Check the weight (GSM)
Look for 180 GSM or more in a round neck. At 220–240 GSM, a white tee or polo is opaque in almost any light. Heavier fabric also hangs better and hides the outline of a vest. More in what GSM means.
Check the knit
Single jersey, the knit of most t-shirts, is opaque at a good weight if the stitches are tight. Interlock is a double knit, two layers of stitches locked together, so it is noticeably more opaque at the same weight. That is why a heavyweight interlock polo is one of the safest whites you can buy. See interlock vs piqué.
Check the cotton
Long-staple cotton such as Supima spins a finer, denser yarn with fewer loose ends, so the fabric stays smooth and does not thin out with washing the way short-staple cotton can.
How to test it
- Hold it up to a window or a light: you should not see your hand clearly through one layer.
- Put your hand inside and stretch it gently: the colour of your skin should barely show.
- On a product page, look for the GSM and the composition. If neither is given, assume it is light.
What to wear underneath
Wear a vest close to your skin tone. A white vest shows through a white tee as a bright outline; a skin-tone vest disappears. Better still, choose a tee heavy enough not to need one.
Keeping whites white
Wash whites separately in cool water, inside out, and dry them in the shade. Treat sweat marks early: see how to remove sweat stains.
Abraca's whites
The white Gutmann polo is 100% Supima in a 240 GSM interlock, so white stays opaque. The white Lokee round neck, for men and women, is a 180 GSM Supima jersey: light for summer, but substantial enough not to turn see-through.
White t-shirt questions
What GSM white t-shirt is not see-through?
Generally 180 GSM or more for a round neck. At 220–240 GSM a white tee or polo is opaque in almost any light.
Why is my white t-shirt see-through?
It is usually too light (low GSM), loosely knitted, or stretched tight across the body. Short-staple cotton also thins with washing.
What should I wear under a white t-shirt?
A vest close to your skin tone. A white vest shows through as a bright outline.
Is a white polo less see-through than a t-shirt?
Often, yes: polos are usually heavier, and interlock polos are a double knit.
Do white t-shirts get more see-through over time?
Cheap ones do, as loose short fibres wash out. Long-staple cotton holds its density better.
