1. Material. I’d recommend to buy socks made of extra-long staple cotton (Egyptian, Sea Island, Pima, Supima) which was mercerised (‘fil d’ecosse‘). It’s good if the yarn is 2-ply or 3-ply. Merino wool blends are great too, especially for autumn and winter (for example, 85% Merino wool + 15% polyamide). Cashmere socks are sometimes very nice, but they’re very expensive, you need to wash them by hand, and some of them are not durable. Cashmere blends can be a good option, if you have a large budget. Silk socks are intended for evening wear; if you have a tuxedo, it’s a good idea to buy a pair of black silk socks.
Merino wool socks.
2. Knitting machines. The finest socks are knitted on machines with 240 or even 276 or 280 needles (examples: Bresciani, Fort Belvedere, Gammarelli, Mazarin). These machines can knit very comfortable, lightweight and flexible socks with excellent fit. Moreover, they allow manufacturers to use small, neat and sophisticated patterns. Socks knitted by 200 needles machines are a bit less luxurious, but they’re fine too. Learn more about 240, 276, 280 needles machines here.
Socks knitted by a machine with 200 or more needles.
3. Length. Always opt for over-the-calf socks (or for invisible socks, if you are going to wear them with moccasins or top-siders). It’s important because otherwise socks may slide down, and your hairy legs will be revealed. If you still want to buy mid-calf socks, remember: the longer the better. Learn more about over-the-calf socks here.
4. Sized socks are a better option than ‘one size fits all’ socks. Some brands offer socks in various sizes: S, M, L, XL, XXL. Buy your size to get the best fit. ‘One size fits all’ socks are not necessarily bad (for example, Marcoliani offers very good ones), but they usually feel less luxurious and in fact they don’t fit all sizes perfectly.
5. Hand-linked toes can be considered as a sign of high quality socks, but it must be noted that toes of some very good socks are not hand-linked. Anyway, hand-linked toes are more comfortable, because toe seams are flat. Read more about hand-linked toes here.
6. Country of manufacturing. The finest socks are usually made in Italy, but you can find high quality socks which were made in the United Kingdom, Germany, Japan or in another country. Italian-made socks are not necessarily excellent.