Underwear under smart trousers

Short answer: Under smart trousers, the edges decide whether your underwear shows. A seamless style or one with a thin, flat edge gives the cleanest line, and the colour matters almost as much.

The edges show through

A thick elastic creates a line through the fabric, especially when you sit or walk. The thinner and flatter the edge, the less it shows. Seamless styles with cut edges give the most invisible transition, while a soft, thin edge is almost as discreet. Read about seamless knickers.

Waist height

If the briefs end at the same point as the trousers, you get a double edge that shows clearly. Choose a different height, so the edges do not sit on top of each other. Low-rise trousers suit high briefs, and high-waisted trousers can work with a lower style. See bamboo briefs.

Choosing a colour

Under light trousers, nude is the least visible, because the contrast with the skin is small. White can actually show more clearly than nude under thin, light fabrics. Under dark trousers, black is the safe choice. Read more about nude knickers.

For men

The same principle applies under smart trousers for men. A close-fitting style with flat edges lies calmly and gives a clean line, while loose styles can bunch up under thin fabrics. Choose a colour that does not contrast with the trousers. See bamboo underwear for men.

The trouser fabric

Thin, smooth trousers show everything underneath. Thicker fabric such as wool and twill hides the edges on its own. If you have trousers in a very thin or shiny fabric, that is where underwear matters most. Keep it in mind when you choose what to wear.

Fit

Underwear that is too tight cuts in and creates a visible bulge above the edge. Underwear that is too loose gathers and folds. Choose by hip measurement, so the briefs fit close without squeezing. It is one of the most overlooked reasons edges show.

See the range

Once you know which height, edge and colour suit your trousers, choosing is easy. A soft, smooth fabric like bamboo viscose lies close to the skin without bunching. See the whole group in bamboo underwear for women.

Washing

Wash at 40 degrees without fabric softener and without a tumble dryer. Heat from the dryer wears the elastic, and a worn edge starts to ripple and show through trousers. Hang underwear to dry, and the edges stay flat longer. Read more in the washing guide.

How many pairs you need

Once you have found a style without visible edges, it is worth buying several of the same. Then you do not need to think about it when the trousers go on, and there is always a pair ready. Many keep three or four pairs only for smart clothes.

For tight trousers

If the trousers are very tight, even a thin edge shows. Here a seamless style or a nude thong is often the only option that does not show. Try the trousers on with the underwear, and check in the mirror both standing and sitting.