Buying underwear online seems straightforward, but a good product photo doesn’t always tell you everything. The fit can vary from one brand to another, fabric compositions are sometimes described in broad terms, and a multipack isn’t automatically good value if the size isn’t right. A few simple checks can help you avoid disappointing purchases, whether you’re shopping for women’s underwear, men’s underwear, thongs, briefs or boxer shorts.
S, M or XL isn’t a fixed standard. One manufacturer’s waist or hip measurements may differ from another’s. Always check the size guide on the product page. Some products list body measurements in centimetres, while others only give a clothing size.
Pay attention to the fit, too:
Terms such as “silky soft”, “antibacterial” or “breathable” sound appealing, but always check the fabric composition and product information. If a brand claims a particular benefit, treat it as a claim made by the brand. According to the manufacturer’s own information, for example, a product may have a special finish or offer a particular comfort benefit; that isn’t the same as an independently verified result.
So, check in particular:
A 3-pack or 5-pack can be handy for everyday essentials, but may be less suitable if you haven’t tried the style before. If the fit is wrong, you could be left with several unworn pairs. For multipacks, also check whether all the items are the same colour, style and size.
Cotton underwear is a practical choice for everyday wear. Cotton feels familiar and is available in different weights and blends. A percentage of elastane usually adds stretch and freedom of movement.
Modal underwear is often chosen for its soft, smooth feel. Products may also contain a modal blend with elastane or other fibres. Always check the official fabric details: the name in the product title may not match the percentages listed in the specifications.
For sports underwear, stretch and a smooth finish matter more than the fibre type alone. According to the product information, the Reebok Serena thong below is made from 92% polyester and 8% elastane and has a seamless design. This may be practical under sportswear, but remember to check the care instructions, too.
Choose a style to suit your clothes and everyday activities:
A seamless style may be less visible under tight trousers or a dress. That doesn’t automatically mean it will be more comfortable for everyone. The right size, leg opening and rise still make all the difference.
For women’s underwear, measure your waist and hips at the points shown in the size guide. For men’s underwear, waist size is particularly relevant, but the height of the waistband and the length of the legs can also affect the fit.
Read the care instructions, too. Some items can be machine washed but shouldn’t be tumble dried. For example, the Calvin Klein 3-pack trunks are listed as machine washable, with tumble drying not recommended. If the care label on the item you receive differs from the online description, always follow the label.
Why it suits this shopper: A set of three is a practical choice if you want to buy several pairs of everyday women’s briefs at once and like having a choice of colours.
The product information lists a 3-pack, available sizes and a stretchy fabric. Be sure to check the exact size and composition before buying.
The description mentions modal; the set includes three colours and a full-coverage style.
Why it suits this shopper: This style is aimed at anyone looking for a well-known brand, a low-rise Brazilian fit and a cotton-modal blend.
The product description clearly states the cut and fabric blend. Compare this information with the size guide before ordering.
The cotton-modal fabric is described as soft and breathable; the low-rise Brazilian cut can help reduce visible lines under some clothes.
Why it suits this shopper: This sports thong is designed for anyone who wants minimal visible lines and plenty of stretch during training.
The product details specify the seamless design, fabric composition and 30 °C wash temperature. This makes it easier to assess whether it’s suitable for sport.
92% polyester and 8% elastane, a stretchy waistband and a design that stays discreet under sportswear.
We’ve put together a complete, up-to-date list of products that meet these strict selection criteria and the applicable European safety requirements.
Measure your waist and hips with a flexible tape measure, then compare the results with the size guide for the specific product. Don’t automatically choose the size you wear in another brand. If you’re unsure, the product measurements matter more than the size letter.
How long it lasts depends on the fabric, how often you wear it, the wash cycle and how you dry it. Elasticated edges can lose their shape more quickly if you often wash them at high temperatures or use a tumble dryer. Follow the care label and rotate several pairs. This means you won’t wear each garment as often.
A multipack can be practical once you know the fit and size. Compare the price per item and check how many pairs you’ll receive. If you haven’t tried the style before, it’s often wiser to try one pair first rather than ordering a large set straight away.