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SEVEN DAY CYCLIST
CYCLING, BUT NOT USUALLY RACING
LATEST UPDATE FEBRUARY 25th 2026
HOW DO WE REACH THE OVERALL RATINGS FOR PRODUCTS WE REVIEW?
Castelli Venti Soft Merino Socks
60g (per pair) L/XL Belgian Blue and White (two pairs) £22.00
The Castell Venti Soft Merino Socks are Castelli’s thickest and warmest socks – according to the blurb. I’ve no reason to doubt this or that they are soft and contain a high merino blend. I have found them comfortable, effective, and suitable for all kinds of cycling, as well as off the bike.
Pros: warm, boxed toe and heel, ankle gripper, length of ankle, quick drying.
Cons: nothing significant.
Specification
Available in white, black, and Belgian blue, the Vento soft Merino Socks are made from a merino and elastic nylon mix. Castelli say they are their “thickest, warmest” socks with a calf-length reach designed to keep your feet warm on long, chilly days – or, indeed, short ones. For thick socks, they a still pretty slim, so don’t worry about your racing shoes or booties. A women’s equivalent is available, Castelli Diciotto Soft Merino socks (a bargain £13.20 – discounted – at the time of writing. Good news is that you may well find the Venti discounted, too (as low as £13.20 at time of writing).
Castelli don’t reveal the ratio of the merino nylon blend. Blends are the norm for merino-based cycling garments. Merino brings warmth, even when damp, and odour protection; the “elastic” nylon brings elasticity and durability. Whatever the exact balance, all those qualities are present (more of that later).
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There’s a reinforced boxed-toe and heel, as well as an ankle gripper. There’s added stretch across the top of the foot. Of course, these do not make the sock unique, but they are very well executed. Seams are barely noticeable, an indicator of high production values. These are lower calf length for a good overlap between sock and tights.
Size and fit 4.25/5
The Venti are available in S/M, L/XL, and 2XL. This covers European sizes 36-47. Castelli recommend using your European shoe size and going up if you are at the top of the size range. I went for the L/XL. The socks fitted like a glove (you know what I mean). With a perfect snug, but not tight, fit, they are great on the bike and away from it. Hide them from the sock thief in your life!
I have worn them under a variety of cycling shoes. Although described as the “thickest”, they really are not thick. These are not hiking socks. They’ve fitted comfortably in general SPD shoes and slimmer sportier designs, too. By the way, I have worn them as base socks under a pair of hiking socks in my hiking boots and with brogues when forced to smarten up. They are just as good.
Care and durability 4/5
No special care is necessary, apart from the usual. I tend to wash technical gear on a lower temperature – even if the 30C is not directed. However, I have bunged these in with the regular laundry and noticed no ill-effects. Mind you, white socks do show the inevitable dirt. How high would I go to get them brilliant white? I have not gone above 40C on a regular wash and that has proved successful in making the white socks presentable. The really good news, whatever the colour, is that the socks emerged barely damp following the spin cycle. Not so dry that I’d put them straight on, but less than an hour in the air got them ride ready. That’s good news for those hand-wash in the sink jobs when on tour. True, it’ll take all night to dry and the anti-pong properties of merino make the need to wash less likely, but I’ll go with that.
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On the bike, inundated winter roads require waterproofing on your feet. However, the merino should keep the frost off until you can get them dry.
The “elastic” nylon should keep the shape of the merino wool even when wringing out by hand. Certainly, some three hundred miles in, plus off-bike wear, and they still look grand; no bobbling, no loose threads, just neat and tidy socks. Of course, I’d expect this, but it is not always the case after wet muddy miles.
Performance 4.25/5
On a general note; I have never come across socks that will, on their own, keep toes toasty on really cold days. The extremities of the body are likely to get chilly and toes are no exception. The temperature at which they do so can be personal. I find overshoes or booties necessary as the temperature drops toward and below zero. I test in this context.
Indeed, it was with overshoes that I first stepped out in the Venti socks; 0C, one hour, nice and warm. Actually, the overshoes were there to protect against too much mud on the mixed surface commute. Road only, at the same temperature, and I still felt ok after an hour or so’s jaunt. With things above zero, just, things were comfortable for three or four hours.
Even with overshoes, feet have never feet clammy. I’ve got a feeling that these socks will be working on into early spring, and beyond. There’ll be some folk who will keep them all through summer. At least, that’s my guess.
The gripper means no sag, even after several washes. Firm though the grip is, it has not marked my delicate lily-white skin. That bit of extra length above the ankle, has combined with the ankle gripper on the bib-tights to effectively excluded unwanted weather.
I have worn them under a variety of shoes. these have included slim SPD shoes, SPD boots, everyday trainers, and brogues. My favourite Fizik Tempo Beat SPD shoes are on the slim side, especially around the instep. Waterproof socks require maximum adjustment; this made me wonder how the extra thickness of the Venti would feel. I’ve usually used the Fizik Winter Socks - thinner, but still effective. Any concerns were quickly dismissed. To be honest, they just feel like socks. Just a bit thicker then everyday ones and rather warmer.
Value 3.75/5
The discounted price puts these in bargain territory; even the rrp is not unreasonable, in my opinion. That could be because I find cold feet on the bike particularly depressing, it could be that age is slowing the circulation to the peripheries. Whatever, for a warm, well-fitting pair of winter socks that dry quickly and stay in place, £22 is well-worth it.
I’ve used the Fizik Winter Socks with great pleasure. They’re cheaper. They are also constructed with thicker and thinner sections to offer warmth and reinforcement in the right places. I’d give the edge in the how low can the temperature go stakes, but the Fizik are definite contenders, especially when combined with overshoes.
Albion offer a winter cycling sock with 48% merino, reinforced toe, and an elasticated cuff for security. At £25 they’re quite pricy, but you can save on a bundle of three pairs. At £28 the Maap Division Merino socks boast 80% merino and have a wide choice of colours. At the lower end of the price range, Madison’s Isoler Merino Socks look to be good contender, but may be better for late and early season rather than midwinter miles. Still, £11.99 is a very tempting price. A similar caveat might apply to apply to the Primal Rebel Socks, at £10. However, they are extra-long, which may well appeal to some.
Of course, there are synthetic models, too. Sportful offer the Snap Winter Socks; specifically shaped for each foot with the usual features, they’re made from Primaloft, a synthetic microfiber material. £26 is pretty much top whack, but with a temperature range of 0-10C, they could go very low when paired with overshoes.
Summary
Toward the top end of the price range, without actually getting there, and sometimes discounted, the Venti Soft Merino Socks are very effective in winter temperatures whilst being slim enough to fit inside your slim shoes. A strong merino element also invites use on tour, as well as the more obvious day or winter training rides. Good of the bike, too, they are perfect for use off the bike as well.
