Castelli Flanders Warm Neck Warmer winter base layer review

Does it work to integrate a neck warmer directly into a base layer?

Castelli Flanders Warm Neck Warmer winter base layer
(Image: © Josh Ross)

Cyclingnews Verdict

The integrated neck warmer isn’t long enough to comfortably pull above your nose, but it does a great job keeping drafts out of your jacket. The Castelli Flanders Warm Neck Warmer winter base layer will see you through the coldest days you choose to venture out in


  • +

    Just right torso length

  • +

    Mesh panel under the arms

  • +

    Integrated neck warmer

  • +

    Fleece fabric


  • -

    Integrated neck warmer is just barely long enough

  • -

    Lots of seams

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When it comes to winter gear there are some companies that have the expertise and others that only do okay, and it's widely accepted that Castelli is among the former category. The Italian brand makes some of the best winter gear on the market, and if you are looking for the right gear to ride hard through the winter, Castelli has options. 

The Castelli Flanders Warm base layer is very much a part of that. It’s a piece we highlighted in our coverage of the Castelli clothing range and it's an obvious contender for inclusion on our list of the best cycling base layers

The Castelli Flanders Warm Neck Warmer takes what is already an excellent winter base layer and extends the neckline. It’s a great way to do something different but does it work? We took this base layer on some of the worst winter rides we did this season and felt out how it worked. Now that we’ve had a chance to get to know it we are ready to share the details. If you are looking for the right base layer for the coldest rides, keep reading to see what we think of the Castelli Flanders Warm Neck Warmer winter base layer.

Castelli Flanders Warm/Neck Warmer winter base layer rear view

Castelli gets the length right and there's no odd bunching above the chamois. (Image credit: Josh Ross)

Design and aesthetics

There are some base layer patterns that shy away from seams. With the Castelli Flanders Warm Neck Warmer winter base layer, the brand has gone the opposite direction. Some people will count each separate piece of fabric as a separate panel. Others will allow that sometimes a panel is more than one piece of fabric. Depending on your preference, this piece comes in at nine or 17 panels. Ultimately it doesn't matter, because that's a lot either way and each piece of fabric requires a new seam to join it to the next. 

The point of all the panels is to get the fit just right. Although the 100 per cent polyester fabric has an impressive amount of stretch, Castelli hedges its bets. Manufacturing manipulates the knit to take advantage of mechanical stretch in a similar way to how carbon fibre layup adjusts flex in a bike frame. Then multiple panels on each side work in a similar way to a pre-curved knee. Even before you slide this base layer on, it has a shape that’s been carefully designed. 

There are also a few extra seams to add extra breathability. To keep you from overheating Castelli chose to break up the heavy fleece fabric used in the rest of the garment. The choice does add extra seams, and panels, but it's likely well worth it to gain a generous section of lightweight mesh under each arm.

More unique than seam and panel decisions is the integrated neck warmer. Castelli makes a version of this base layer that uses a standard neck design. The two options are exactly the same but this version stands apart from that design with the addition of a 19cm/8-inch integrated neck warmer. Only Rapha has a competing product and each option tackles the neck a little differently.

Castelli keeps to a simple folded design for its version of the integrated neck warmer. The fabric is the same as the rest of the Castelli Flanders Warm Neck Warmer winter base layer but it's double-layered. The fleece side is on the inside, between the layers, and there is a fold at the top with a seam in the back.  

Castelli Flanders Warm/Neck Warmer winter base layer detail of the armpit

Castelli uses lots of seams and panels to get the fit just right without the need for added spandex.  (Image credit: Josh Ross)


Sometimes it's not necessary to overthink a garment too much. Does it work or not? The week I got this base layer I took it out for one of the worst weather rides I've done this winter, and it worked. 

The forecast for the day was rain all day and temperatures near freezing. With 100 miles ahead of me, I started with the Castelli Flanders Warm Neck Warmer winter base layer. On top of that I then added the Assos Mille GT Ultraz winter jacket and the Assos Equipe RS rain jacket. I almost always take a Castelli Pro Thermal Head Thingy on my coldest rides but for this ride I opted to leave it at home and test the integrated neck warmer. I was able to stay warm and comfortable in my core even in these conditions, but there are some details to explain.

Getting dressed, a couple of things are obvious about this piece. The neck is narrow and although polyester is stretchy on its own, the lack of spandex is obvious. It's a tight squeeze to get your head through but things are comfortable once situated. Part of that comfort is the perfect length. Often base layers are so long they interfere with the chamois. Castelli keeps things long enough for protection without being so long it requires consideration. 

Out on the bike it's immediately obvious that the integrated neck warmer still needs a separate neck warmer. Standing around you can pull it up but when leaning forward on the bike it's not really long enough to comfortably pull above your mouth and nose. It's not impossible but once situated any movement will cause it to come down. That doesn't mean it's not worthwhile, it’s just not quite as versatile as it could be. It perfectly fills the space in the neck of a jacket and keeps any cold air from penetrating at the neckline, only your face is hard to cover. 

Castelli Flanders Warm/Neck Warmer winter base layer detail of the interior fleece

The brushed interior helps hold heat and will keep you warm in the coldest weather you want to ride in.  (Image credit: Josh Ross)


There is no weather I would venture out in where the Castelli Flanders Warm Neck Warmer wouldn't be enough to keep me warm. I also really appreciate that Castelli nails the length of this piece. An overly long torso on a base layer means it has to bunch up at the top of your bib tights and Castelli avoids that issue. You will want to continue to pack your favourite neck warmer though if you like to pull it up over your face. 

The performance is there but that doesn't mean there isn't room for improvement. The addition of a generous percentage of elastane/spandex into the fabric would be welcome. Along the same lines, I'd love to see less reliance on seams to get the fit just right. 

Tech Specs: Castelli Flanders Warm Neck Warmer

  • Price: £90 / $104.99 / €79.95 / AU$140
  • Materials: 100% Polyester
  • Available Colours: Grey, Black
  • Available Sizes: XS-XXL
  • Weight: 166g size small

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