Castelli Gregge 15 socks review

A low-profile merino sock to keep you warm when the weather is cool

Cycling Weekly Verdict

The low volume and thermal properties of the Castelli Gregge 15 socks make them perfect for pairing with summer shoes on cooler days. They’re cosy and comfortable to put on and remain so even on longer rides. They are a little expensive for a sock, but they do justify this by their performance.

Reasons to buy
  • +


  • +


  • +


Reasons to avoid
  • -

    Merino content lower than some competitors

You can trust Cycling Weekly. Our team of experts put in hard miles testing cycling tech and will always share honest, unbiased advice to help you choose. Find out more about how we test.

The Castelli Gregge 15, with its middle-of-the-road 15cm cuff and 50 per cent merino content, is a more versatile sock, intended for a broader range of conditions and riding styles than a dedicated winter item. If it's maxed-out warmth you’re after, you’d be better off with Castelli’s Primaloft socks.

The qualities of merino wool make it ideally suited for cycling socks in colder climes. In being naturally antibacterial, your feet stand to be fresher after a ride, while the thermal properties – which remain to a surprising degree, even when wet – promise to keep your toes toasty.

Thank you for reading 20 articles this month* Join now for unlimited access

Enjoy your first month for just £1 / $1 / €1

*Read 5 free articles per month without a subscription

Join now for unlimited access

Try first month for just £1 / $1 / €1