The 11 Best Base Layers for Cycling in Winter

Last Updated on 13 January 2026 by Cycloscope

10 of the best base layers for cycling in winter, produced by the warmest clothing brands.
Merino wool base layers, synthetic fabric, and mixed fabric.

During our recent bikepacking trip in the Himalayas, we appreciated, like never before, the importance of a good thermal base layer for cycling.

A quality winter base layer makes the difference, feeling protected from the cold and not wet with sweat, even when riding in cold temperatures, is probably the most important single thing while cycling in winter.

A base layer for cyclists is the first layer next to the skin during cycling, particularly in cold weather. It is typically made from moisture-wicking and insulating materials such as merino wool, synthetic blends, or thermal fabrics. The primary purpose of a base layer is to provide comfort, regulate body temperature, and manage moisture during winter rides.

As you cycle, your body generates sweat, even in cold weather. If this sweat remains close to your skin, it can make you feel cold and uncomfortable. Base layers are designed to wick moisture away from the skin, moving it to the outer layers of clothing where it can evaporate more easily. This keeps you dry and helps regulate your body temperature, reducing the risk of catching the flu.

In this guide, we have selected the warmest winter base layers produced by the best cycling clothing brands. To offer a more complete overview, we have chosen both merino wool base layers and synthetic fabrics, as well as a mix of the two.

Some of these products have a baseline layer for women, while others are unisex. We will soon write a guide dedicated to the best base layers for women.

And remember, buying winter clothing in the summer is not a bad idea at all; prices are much lower, and many companies are trying to clear out their warehouses to make room for new collections.

The 10 Best Winter Base Layers for Cycling – Synthetic Fibers + Mix + Merino

1. Castelli Flanders Long Sleeve

synthetic base layer

around 90 USD

• Ideal For: extending your winter jacket temperature range.
• Temperature: -2°C – 10°C / 28°F – 50°F
• Fabric: 100% polyester – SottoZero Fleece multi-denier polyester
• Size: XS, S, M, L, XL, XXL
• Machine Wash: Castelli suggests hand washing only
• Colors: 2 (Black, Grey)

Castelli, a historic Italian clothing brand founded in 1876, is almost always a guarantee. And it certainly is this time: with the Castelli Flanders Long Sleeve cycling base layer, you’ll stay dry and warm during your winter or cold-weather rides thanks to its excellent insulation.

This model is available in 6 sizes, from extra small to XXL. Check the Castelli size guide to be sure you have the right size for you. Even though sizes are quite standardized, a medium in Italy may be larger or smaller than a medium in another country. The fit is comfortable; it is not a compression base layer.

The mesh armpit insert helps ventilation and thermoregulation.

Note that both the male and female Flanders base layers are not windproof or waterproof, so do not forget your rain jacket.

2. Endura BaaBaa Blend Long Sleeve Cycling Men’s Baselayer

synthetic + wool base layer

around 50 USD

• Ideal For: winter riding
• Temperature: around 0 °C
• Fabric: 80% Lyocell, 20% Wool
• Size: S, M, L, XL, XXL
• Machine Wash: yes
• Colors: 3 (Black, Blueberry, Paprika)

The base layer uses soft Merino wool from sheep raised without mulesing, a practice deemed cruel by numerous animal welfare organizations and, in common sense, unnecessary. Instead, they adopt more humane approaches to prevent infection.

This ethical choice not only ensures kindness towards animals but also offers a gentle touch to your skin, providing unparalleled comfort without any scratchiness.

Additionally, the wool’s naturally odor-resistant properties, coupled with its lightweight design, deliver ample winter warmth for a truly cozy experience.

3. Giordana Mid Weight Long Sleeve

synthetic base layer

around 50 USD

• Ideal For: fall/mild winter riding
• Temperature: 4°C – 15°C / 40°F – 60°F
• Fabric: 100% Synthetic
• Size: S, M, L, XL
• Machine Wash: Hand wash only
• Colors: 1 (White)

The thermal base layer features an innovative Dryarn™ fabric, meticulously engineered to wick moisture away from your skin, promoting rapid evaporation that keeps you consistently dry and enveloped in optimal comfort throughout your cycling escapades.

Its inherent anti-bacterial properties further enhance the experience, providing an added layer of freshness during prolonged rides.

Crafted from a tubular knit microfiber, this base layer is designed to sit snugly against the skin, expediting moisture movement away from the body, bolstering its efficacy in keeping you dry even during the most demanding cycling sessions.

The midweight construction of this base layer demonstrates a strategic approach, skillfully limiting the number of ventilation panels to precisely regulate your core temperature.

This level of temperature control is especially advantageous when riding in temperatures ranging from mid-60°F to low 40°F, ensuring you stay adequately insulated without compromising on breathability.

4. Rapha 100% merino Base Layer

Merino base layer

around 45 USD

• Ideal For: extremely cold riding
• Temperature: 4°C – 15°C / 40°F – 60°F
• Fabric: 100% New Zealand Merino
• Size: XS, S, M, L, XL
• Machine Wash: yes
• Colors: 1 (Grey)

Unlike Rapha’s regular base layers, the Winter Base Layer boasts a heavier-weight yarn. It features a roll-neck design that can be worn conventionally for standard insulation or pulled up over your face, providing the same functionality as the renowned Rapha Winter Collar.

To ensure maximum comfort, the Winter Base Layer features raglan sleeves, preventing bag straps from rubbing against your skin.

Additionally, the implementation of flatlock seams guarantees a chafe-free experience throughout your ride. Embrace the cold with confidence, unparalleled coziness, and performance for your cycling adventures.

The Winter Base Layer is meticulously crafted from 100% New Zealand merino, featuring an 18.9-micron yarn for unmatched softness against your skin. This natural fiber is not only incredibly gentle but also itch-free, possessing excellent moisture-wicking properties and inherent resistance to odors.

5. Green Rose Merino Base Layer

Merino wool

around 45 USD

• Ideal For: extremely cold riding + winter camping
• Temperature: N/A
• Fabric: 100% Organic Merino Wool Fabric
• Size: XS, S, M, L, XL, XXL, XXXL
• Machine Wash: yes, temperature not higher than 40°C
• Colors: 7 (Black, White, Petrol, Light Blue, Grey, Khaki, Dark Green, Brown)

Green Rose is a small company based in Vilnius, Lithuania. They produce and sell organic and natural clothing made from hemp and merino wool.

They pride themselves on using only natural products, no chemical colors whatsoever, and we can confirm their clothes really feel great on the skin and do not cause any irritation, even to someone like me who also had allergic-type reactions to wool.

You can have a look at our full Green Rose Merino Review here.

6. Rapha MEN’S PRO TEAM THERMAL BASE LAYER – LONG SLEEVE

synthetic base layer

around 46 USD

• Ideal For: extremely cold riding
• Temperature: N/A
• Fabric: Front 84% Polyester, 16% Spandex – back 91% Polyester, 9% Spandex
• Size: XS, S, M, L, XL, XXL
• Machine Wash: yes
• Colors: 3 (Black, Dark Red, Dark Navy)

The Pro Team Thermal Base Layer is tailored for high-tempo riding and racing in freezing or near-freezing temperatures, drawing inspiration from the Deep Winter Base Layer and infusing it with Pro Team technical innovation.

Constructed from a polyester fabric with a subtle bobbled texture against the skin, this base layer effectively traps air to provide exceptional warmth while maintaining its quick-drying and fast-wicking properties.

This ensures that even during intense efforts and sweating, moisture won’t hinder your cool-down process.

Enhancing visibility under dark skies, reflective bars are printed on the neck, while the tall snood covers the face and ears when worn high. As with all Pro Team products, the base layer is designed for a low on-the-bike position, empowering you to ride at full throttle throughout the winter.

7. Le Col Base Winter Long Sleeve Base Layer

synthetic base layer

around 100 USD

• Ideal For: Winter ridings
• Temperature:  -5 to 5 °C 
• Fabric: Inner fabric is 100% Recycled Polyester, Outer fabric: 88% Polyester and 12% Elastane.
• Size: XS, S, M, L, XL, XXL
• Machine Wash: Machine Wash at 30°C / 86°F
• Colors: 1 (black)

Introducing the Winter Long Sleeve Base Layer, a carefully engineered garment that keeps your core warm even on the coldest days.

Designed to sit close to the skin and worn under your jacket as part of an effective layering system, this Winter base utilizes the innovative Polartec® Alpha™ on the interior layer and Polartec® Powergrid™ Fleece on the exterior, ensuring unrivaled thermal protection.

Ergonomically tailored for a snug fit, this base layer boasts a lightweight, low-bulk construction that guarantees optimal warmth retention, even when temperatures plunge into negative territory.

The combination of Polartec® fabrics strikes a perfect balance between warmth and minimal bulk, delivering unparalleled comfort during your cold-weather rides.

Initially developed for the U.S. special forces, Polartec® Alpha™ is engineered to regulate comfort in dynamic conditions, delivering unwavering warmth and breathability amid extreme temperature variations without requiring layer removal.

These qualities resonate perfectly with the needs of cyclists braving the chillier months.

On the other hand, Polartec® Powergrid™ features a patented grid-knit construction, elevating warmth and breathability while reducing fabric mass.

This ingenious design makes it an ideal choice for crafting high-performance cycling apparel, ensuring you stay cozy and comfortable as you conquer the winter rides.

8. POC Essential Layer LS Jersey

synthetic base layer

from 50 USD

• Temperature: N/A
• Fabric: polyester/elastane 
• Size: S, M, L, XL, XXL, XSM
• Machine Wash: N/A
• Colors: 3 (hydrogen white, light base light blue, uranium black)

Layering properly is the key to staying warm. On the road or the trails, in a race, or on any weekend ride, this long-sleeve jersey is the ideal base layer for cooler conditions.

With a close fit, the lightweight base layer offers high breathability and exceptional wicking, vital for staying warm, dry, and comfortable on any ride.

Developed for a close fit against the skin, the jersey features flatlock seams for exceptional comfort and stretch panels on the sides to ensure it moves with you. A small POC logo features on the chest.

9. Dhb AERON POLARTEC LONG SLEEVE BASE LAYER

synthetic base layer

from 26 USD

• Temperature: N/A
• Fabric: 100% Polyester
• Size: XS, S, M, L, XL, XXL
• Machine Wash: N/A
• Colors: 1 (trekking green)

DHB incorporates fabrics from American innovator Polartec® into their winter baselayers, such as this performance long sleeve crafted with Power Dry™, a remarkable fusion of hydrophilic and hydrophobic fibers.

The Power Dry™ bi-component knit ensures continuous evaporation, preventing this race-fit baselayer from becoming saturated and effectively regulating your core temperature. The high-neck design of this winter warmer also helps ward off the cold.

The Aeron Polartec Long Sleeve Baselayer is perfected with the superior strength and flexibility of ActiveSeam technology, guaranteeing an excellent performance fit every time. These strategically placed seams provide supreme comfort while riding.

Polartec® is renowned for creating the most cutting-edge performance textiles available today. Originating as the original synthetic fleece, Polartec® now offers a collection of over 300 diverse fabrics, specially designed to keep you warm, dry, and, above all, comfortable during various outdoor activities.

10. Isadore Merino Deep Winter Baselayer

Merino wool + Synthetic fabric

from 115 USD

• Temperature: Zero and sub-zero temperatures
• Fabric: 40% Merino wool, 60% Polyamide
• Size: XS, S, M, L, XL, XXL
• Machine Wash: N/A
• Colors: 2 (purple, black)

Despite its surprisingly thin appearance, the Merino Deep Winter Baselayer is exceptionally warm due to its intelligent blend of Merino wool and Polyamide. This seamless knit garment features a longer torso for maximum coverage and a turtleneck design to prevent chilly winds from reaching your chin.

The longer arms with thumbholes provide added protection for your wrists against persistent wind. The chest area is reinforced with an ultra-thin and elastic membrane fabric that acts as a barrier against the harshest winds.

This base layer offers a snug fit and includes thumb loops to keep it securely in place. Additionally, it features an extra-long turtleneck for even more warmth and protection during cold-weather activities.

The Secret To Warm Winter Cycling? Layer Up!

Layering is the key to staying warm and comfortable while cycling in cold winter conditions. It allows you to adjust your clothing as needed during the ride. If you start to feel too warm, you can peel off a layer or unzip your jacket.

It’s essential to find the right balance between staying warm and preventing excessive sweating, as sweating too much can make you colder once you stop moving. Here’s a guide on how to effectively layer up for winter cycling:

1. Base Layer: Start with a moisture-wicking base layer that sits directly against your skin. This layer helps to keep sweat away from your body, keeping you dry and preventing chills.
2. Cycling Jersey: your regular jersey, breathable and moisture-wicking.
3. Arm warmers: provide temperature regulation, sun protection, and portability. Combining leg and arm warmers with base, insulating, and outer layers allows for comfort in varying winter conditions, adapting quickly to changing temperatures without excessive clothing.
4. Insulating Layer (Softshell): The insulating layer traps your body heat, keeping you warm. It could be a fleece or thermal jersey, or even a lightweight down jacket, depending on the temperature.
5. Hardshell (Windproof and Waterproof Outer Layer): Protect yourself from the elements by wearing a windproof and waterproof cycling jacket. This outer layer will shield you from cold winds and potential rain or snow.
6. Layering Accessories: Consider adding extra layers to your core, like a gilet or vest, that you can easily remove if you get too warm during your ride.

Additional gear for winter:

1. Leg Warmers: Leg warmers are tube-like garments that roll up or down your legs, providing additional warmth and protection. They are typically made of thermal and moisture-wicking materials.
2. Cycling Tights or Pants: Opt for thermal cycling tights or pants to keep your legs warm during the ride. Look for ones with windproof panels in the front to add extra protection.
3. Gloves: Cold hands can be uncomfortable and affect your grip on the handlebars. Wear insulated and windproof cycling gloves to keep your fingers warm.
4. Headgear: A lot of heat escapes through your head, so wearing a thin beanie or a thermal cycling cap under your helmet can help retain that warmth.
5. Neck Warmer or Buff: Keep your neck and lower face protected from the cold by using a neck warmer or buff. It can be pulled up over your chin and nose if the temperature drops.
6. Cycling Shoes and Toe Covers: Insulated cycling shoes or shoe covers are essential for keeping your feet warm and protecting them from cold wind. Toe covers can be added for extra insulation.

Merino Base Layer for Cycling vs. Synthetic Base Layer for Cycling: Making the Right Choice

As you embark on your quest to find the ideal base layer for cycling, one of the fundamental decisions you’ll encounter is choosing between a merino wool base layer and a synthetic fabric base layer. Both options boast unique properties and advantages, catering to different preferences and cycling conditions.

Merino Wool Base Layer

Luxurious Comfort and Natural Performance

Merino wool base layers are renowned for their luxurious softness, offering unparalleled comfort during extended rides. The fine fibers of merino wool are much softer than traditional wool, making it non-itchy and gentle on the skin. Cyclists who prioritize comfort and enjoy the sensation of natural fibers against their skin often find merino wool to be a delightful choice.

Thermal Regulation for Diverse Conditions

One of the standout features of merino wool is its exceptional thermal regulation. This natural fiber has unique insulating properties, effectively retaining body heat during colder rides while also providing breathability to prevent overheating in warmer conditions. This adaptability makes merino wool base layers a versatile choice for cyclists who tackle varying weather conditions.

Moisture Management and Odor Resistance

Merino wool excels at wicking moisture away from the skin, keeping you dry even when you’re sweating during intense cycling sessions. Moreover, this remarkable fabric has natural antibacterial properties that combat odor-causing bacteria, making it a great option for multi-day rides or for those who prefer not to wash their base layers after every use.

Synthetic Base Layer

High Performance and Quick Drying

Synthetic base layers are engineered to deliver high-performance moisture-wicking capabilities. The synthetic materials used, such as polyester or polypropylene, effectively draw sweat away from the skin, accelerating evaporation and keeping you dry during intense rides. This quick-drying ability is particularly beneficial for cyclists engaging in high-intensity workouts or cycling in wet conditions.

Lightweight and Easy Maintenance

Synthetic base layers are typically lighter than their Merino wool counterparts, offering a lightweight feel that minimizes bulkiness under your cycling jersey. Additionally, synthetic fabrics are easy to care for and can be machine-washed without concern for potential damage or shrinkage, making them a convenient choice for cyclists with active lifestyles.

Affordable and Durable

In general, synthetic base layers tend to be more budget-friendly than merino wool options. Moreover, synthetic fabrics are durable and resilient, retaining their shape and performance even after numerous washes and prolonged use.

The Verdict

Ultimately, the choice between a merino wool base layer and a synthetic base layer boils down to personal preference and specific cycling conditions. If you prioritize luxurious comfort, natural insulation, and odor resistance, merino wool may be the ideal choice.

On the other hand, if high-performance moisture management, quick-drying capabilities, and budget considerations are at the forefront, a synthetic base layer might be the better fit.

Note: Temperature recommendations are general guidelines, as individual cyclists perceive temperature differently based on various factors.

Your unique riding style, whether high-output efforts or low-intensity training, and the type and weight of your base layer or long-sleeve jersey can significantly influence the effective temperature range.

As such, your personal experience may lead you to extend or narrow the recommended temperature range, allowing you to tailor the base layer’s use to your specific preferences and conditions.

Wrap-Up: Winter Base Layers for Cycling?

By wearing a base layer during winter rides, you create a foundation for your clothing system that actively manages moisture and temperature, keeping you comfortable and better equipped to focus on your cycling performance. It is an essential part of layering strategies for staying warm and dry in cold-weather cycling.

Gearing up for Winter? Check also:

• The 9 Best MTB Winter Jackets – Waterproof, Softshell, Windbreakers
• The 12 Best Cycling Overshoes: Waterproof Shoe Covers for Winter
• Winter Cycling Pants: 9 Best Tights and Bibs for Cold-Weather Biking
• The 8 Best Winter Cycling Gloves for Road Cycling, MTB, Bikepacking & Bike Commuting
• 10 Best Cycling Socks from Winter to Summer in 2026
• 11 Best Winter Cycling Jackets Reviewed – Hardshell, Softshell, and Fleece from Cheap to Top