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Castelli's Premio 18 socks are extremely comfortable thanks to way they are designed with 'zones', and the level of detail in their construction goes a long way to justifying that price tag. Do check the sizing, though – they come in three sizes, but those don't equate to what you might expect (L/XL – 40-43?) and they can be a faff to pull on even if you’ve got the right size.
Read our guide to the best cycling socks for more (and cheaper) options.
There is no denying that a proper pair of cycling socks can make a huge difference to your foot comfort compared with a standard pair from your local clothing store, thanks to the material used and seam positioning and so on.
These Castelli socks highlight this. They have a construction where certain sections of the sock have a different knit pattern to allow movement, create support and improve breathability, and once on they feel exceptional.
The main things I noticed when wearing them is that there is a very subtle feeling of compression around the midfoot, which gives support around the arch when constantly pressing down hard on the pedals, while the bottom layer of the sock has a thickness that gives a bit of cushioning without feeling bulky at all.
Breathability is great, and the fact that they are made from Meryl Skinlife fabric means they remain stink-free as it has bacteria-quashing properties. Ideal, as you don't have to keep washing them after every ride – well, unless you want to.
Speaking of washing, with this review pair being white (darker colours are available – black, Belgian Blue, and Deep Green) they did get quite dirty from dusty roads and gravel trails, but even on a cool 30°C wash they came up clean every time.
So, performance-wise – awesome! They really are.
I've got probably 30 pairs of cycling-specific socks and these are easily in the top three for comfort, but the only downside with all of this ‘zone-specific' construction and/or the material is that there isn't a huge amount of stretch to make them easy to get on – even if they’re the right size for your feet…
I have to confess I didn’t check the size guide before testing these. “L/XL”, yep, that’s me. Except this is Castelli… so L/XL is everyone else’s M or M/L…
It goes: S/M (36-39), L/XL (40-43), 2XL (44-47). I’m a 44/45. My wife, though, is size 40, and even she found these a struggle to get on. Plus, if you don't line them up perfectly, forget about trying to twist them around your foot while they are on.
Even if you buy the right size, my advice would be, don't grab these if you are in a rush, and don't try to put them on if your feet are at all clammy or damp. If you have the time to sit down and ease the socks on, though, they'll feel lovely.
These are definitely going to be some socks that you want to look after as well, as they cost £26. Thankfully, the build quality is very good; after a month of near everyday use for both cycling and running, they are still looking like new, with no signs of bobbling or wear.
They're more expensive than most we've tested, though: the Giro Hrc+ Grip socks that George was reasonably impressed with are £23.99, and even the 'designer' Universal Colours Spectrum Tie-Dye Merino socks that Steve found very comfortable are 'only' £25.
Apart from waterproof offerings, those two are the most expensive socks we've tested recently. And many others that have performed well are much cheaper, like the Orro Sportive socks at £9.99, or the Assos Poker Socks 3 for £16.
If you are happy to faff a bit with getting them on then you will be very pleased with the Premio 18s' performance and comfort. The outlay is big, but I can't find any issues with durability, so these look likely to last for many miles without issue.
Not easy to get on, but once in place they are very, very comfortable
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road.cc test report
Make and model: Castelli Premio 18 Socks
Size tested: L/XL
Tell us what the product is for
Castelli says, "The Castelli Premio 18 Socks earn their stamp of quality with thoughtful construction, measures to safeguard your foot health, and incorporation of the brand's best technologies to help you forget your feet and concentrate on the road."
Tell us some more about the technical aspects of the product?
Multiple structure knit means best performance in each part of the sock
200-needle construction adds stretch
Asymmetrical construction mirrors shape of foot
Supportive band at midfoot, with cushioning pad at ball
Constructed from Meryl® Skinlife yarns with antimicrobial silver ions
Even a size too small, once on, fitted comfortably.
They equate to the size guide – just be aware that Castelli's size guide doesn't equate to most sock size guides…
How easy is the product to care for? How did it respond to being washed?
They cleaned up well from rides full of dust and mud without any staining.
Tell us how the product performed overall when used for its designed purpose
Incredible fit and performance once seated correctly.
Tell us what you particularly liked about the product
Tell us what you particularly disliked about the product
The faff to get them on (even if you have the right size). And that price.
How does the price compare to that of similar products in the market, including ones recently tested on road.cc?
These are some of the most expensive socks we've reviewed recently, and while the design and technology is very impressive, it's not streets ahead of others we have tested that are around half the price, like those mentioned in the review.
Did you enjoy using the product? Yes
Would you consider buying the product? Yes
Would you recommend the product to a friend? Yes
Use this box to explain your overall score
Hugely comfortable, but they don't have the stretch of many other socks, which makes getting the position on your foot critical. They're expensive but well made and durable. A bit of a mixed bag for the daily cyclist, but awesome for race day.
About the tester
I usually ride: This month's test bike My best bike is: B'Twin Ultra CF draped in the latest bling test components
I've been riding for: Over 20 years I ride: Every day I would class myself as: Expert
I regularly do the following types of riding: time trialling, commuting, club rides, sportives, fixed/singlespeed,
As part of the Tech Hub here at F-At Digital, our senior product reviewer Stu uses the knowledge gained from putting well over a 1,000 products through their paces (including hundreds of bikes) to write in-depth reviews of a huge range of kit. After first throwing his leg over a race bike back in 2000, Stu's ridden more than 160,000 miles on road, time-trial, track, and gravel bikes, and while he's put his racing days behind him he still likes to smash the pedals rather than take things easy. Although, as he spends a fair bit of his time reviewing ebikes these days he's becoming an expert in letting the motor take the strain. He's also waiting for 23mm race tyres to make a comeback!