Best S Mens Base Layers in 2026

Check the size chart of the third picture to select the appropriate size

4-way stretch construction moves better in every direction, tight fitting,like a second skin

Moisture Transport System sweeps away sweat and dries quickly; Flat lock seams to prevent chafing

With a gusseted no-bunch crotch and low-profile elastic waistband, the CORE Lightweight Bottom provides just enough warmth for when temps dip and dial up animal activity. Featuring permanent Polygiene Odor Control technology to neutralize odor by stopping the growth of odor. The CORE Lightweight Series is the next-to-skin layering foundation for SITKA Systems, actively moving moisture away from the skin while keeping the hunter dry and comfortable.

GORE OPTIFADE Concealment Elevated II is designed for whitetail hunters in an elevated position.

Fabric: Quick-Dry, Lightweight Comfort Stretch Knit (100% Polyester).

100% merino wool

imported

machine wash

Updated design

Offset shoulder seams prevent pack rub

Flatlock seams prevent chafing

Plus sizes 3XL, 4XL, 5XL, 6XL and 7XL for wide calves. Single rib welt technique achieves true graduated compression which won’t be too tight at the top of the sock thereby presenting more comfort.

Helical construction provides compression 20-30 mmHg with breathability, which is snug at the calf, allowing the socks to be worn for long period of time.

The right angle L-shaped design combined with ergonomics is a perfect match for your foot, which are snug at the heel.

WOOL HALF ZIP FOR MEN: This half zip long sleeve top for men fits effortlessly under mid & outer layer pieces for the ultimate cool weather adventure. The odor resistant and comfortably worn top helps regulate your temperature.

WOOL LIGHTWEIGHT SHIRT: This wool top for men has flatlock seams to prevent chafing & underarm gusset for comfort & mobility. This wool base layer is crafted of 100% merino wool.

MERINO WOOL LAYERS: Stay warm from head to toe in Icebreaker outdoor clothing gear. Keep covered in wool gloves, glove liners, mittens, bras, wool base layers such as tops, under shirts, leggings, bras, underwear & more.

The Perfect Base Layer: Be ready for the ultimate cool weather adventure with the Icebreaker Merino 175 Everyday Long Sleeve Base Layer for men! These half-zip sweaters for men are available in multiple colors and will keep you warm anywhere.

Reliable Materials: Our 100% Merino wool shirts for men are perfect for any adventure! This breathable half-zipper men’s shirt naturally resists odors, helps regulate temperature in all weather conditions, and manages moisture for all-day comfort.

Versatile and Comfortable: Designed to make sure you’re prepared for any cool weather adventure, these thermal warm wool sweaters for men have a stretchy, slim fit for easy layering - so you’re ready for snowboarding, skiing, hiking and more!

WARM HEAVYWEIGHT base layer for extreme cold activities

SUSTAINABLY CRAFTED from 100% recycled, ECO-friendly fibers

ZEROSCENT ANTI-ODOR technology engineered into the fabric helps you stay fresh

Cold-Weather Layering Foundation: Stay warm and comfy all year long with the Icebreaker Merino Standard 175 Warm Leggings for men! These insulated long johns for men are thermal to regulate body temperature, and match our Everyday Zip or LS crew top.

Reliable Materials: Made with 100% Merino wool, these warm men’s leggings are super-soft, and our winter pants for men naturally resist odor and manage moisture. This Merino wool base layer will keep you cool when it’s hot and warm when it’s cold.

Perfect Everyday Fit: Designed with a slim, contoured fit to help provide smooth cold weather layers, our men’s long underwear and men’s thermals are perfect whether you’re camping on a chilly summer night or enjoying a frigid winter adventure!

Cold-Weather Layering Foundation: Stay warm and comfy all year long with the Icebreaker Merino Standard 175 Warm Leggings for men! These insulated long johns for men are thermal to regulate body temperature, and match our Everyday Zip or LS crew top.

Reliable Materials: Made with 100% Merino wool, these warm men’s leggings are super-soft, and our winter pants for men naturally resist odor and manage moisture. This Merino wool base layer will keep you cool when it’s hot and warm when it’s cold.

Perfect Everyday Fit: Designed with a slim, contoured fit to help provide smooth cold weather layers, our men’s long underwear and men’s thermals are perfect whether you’re camping on a chilly summer night or enjoying a frigid winter adventure!

Special one leg cutting design, dynamic and unique non-symmetrical design.

Made of polyester and spandex, ultra-soft ,comfort, keep good feeling in exercise.

Grip your muscle tightly, shape the body and protect the muscles well in active exercise.

[EASY CARE]: Machine wash cold.

[ATHLETIC CUT]: Allows total mobility but eliminates that bulk of extra fabric.

[KEEP DRY & COMFORTABLE]: Combine the benefits of merino wool with coolmax microfiber. This athletic tee transports moisture away from your skin to the surface of the fabric where it evaporates quickly to help keep you dry and comfortable.

OMNI-SHADE: Be safe and protected. Omni-Shade blocks UVA and UVB rays to help prevent sunburns and long-term skin damage. The tight weave construction with UV absorbent yarns block the full spectrum of harmful sun rays

OMNI-WICK: The ultimate moisture management technology for the outdoors. Omni-Wick quickly moves moisture from the skin into the fabric where it spreads across the surface to quickly evaporate—keeping you cool and your clothing dry

MADE TO HUNT: Made from a polyester interlock quick-drying material, this is a shirt you can wear proudly on its own, or wear as a wicking base layer for extra warmth and all day comfort. A shirt ready for all your epic wilderness trips

Material: Magic Mesh (100% polyester)

Insulation Weight: ultralight

Fit: form-fitting

NORDIC PERFORMANCE: Designed in Sweden - a land blessed with 200 days of challenging conditions.

BUILT FOR THE COLD: Advanced zip-turtle long-sleeve running top made of highly functional polyester jersey with loop back for extra comfort and warmth.

OPTIMAL VENTILATION: Mesh at armpits for enhanced ventilation and fold-over sleeve ends with thumb grip to keep hands warm during cold days. Zip turtleneck for easy ventilation.

NORDIC PERFORMANCE: Designed in Sweden - a land blessed with 200 days of challenging conditions. Our highly functional ADV SubZ LS Tee is built for dedicated athletes who work out with a purpose.

BUILT FOR THE COLD: Advanced zip-turtle long-sleeve running top made of highly functional polyester jersey with loop back for extra comfort and warmth.

OPTIMAL VENTILATION: Mesh at armpits for enhanced ventilation and fold-over sleeve ends with thumb grip to keep hands warm during cold days. Zip turtleneck for easy ventilation.

Mens fashionable elastic ski pullover

Men

M/L

OMNI-SHADE: Be safe and protected. Omni-Shade blocks UVA and UVB rays to help prevent sunburns and long-term skin damage. The tight weave construction with UV absorbent yarns block the full spectrum of harmful UV rays.

OMNI-WICK: The ultimate moisture management technology for the outdoors. Omni-Wick quickly moves moisture from the skin into the fabric where it spreads across the surface to quickly evaporate—keeping you cool and your clothing dry.

PFG COMFORT & BREATHABILITY: Made from a polyester interlock quick-drying material, this fishing shirt is right at home on the water or hanging out at a beachside campfire.

Made of high quality cotton, comfortable skin touch with good air breathable.

100% brand new. Easy cleaning and fast drying.

Soft and light weight, slim fit, nice choice for active, gym, workout, sleepwear, etc.

NORDIC PERFORMANCE: Designed in Sweden - a land blessed with 200 days of challenging conditions. Our highly functional ADV SubZ Wind Pants are built for dedicated athletes who work out with a purpose.

BUILT FOR THE COLD: Advanced running pants featuring wind- and waterproof 2-layer Ventair Wind fabric at front and brushed jersey made of recycled polyester at lower leg and back.

SNUG FIT: Wide waistband with adjustable drawstring for snug fitting.

NORDIC PERFORMANCE: Designed in Sweden - a land blessed with 200 days of challenging conditions. Our highly functional ADV SubZ LS Tee is built for dedicated athletes who work out with a purpose.

BUILT FOR THE COLD: Advanced zip-turtle long-sleeve running top made of highly functional polyester jersey with loop back for extra comfort and warmth.

OPTIMAL VENTILATION: Mesh at armpits for enhanced ventilation and fold-over sleeve ends with thumb grip to keep hands warm during cold days. Zip turtleneck for easy ventilation.

Lightweight, Deluxe Comfort: Offset, flatlock seams on the shoulders and sides make for a more comfortable day of backpacking on your favorite trail, while the UPF 20+ helps keep you covered from the sun

Classic Look, Casual Fit: This long sleeve tee is designed to keep you comfortable while you’re active and feeling great while you’re out, with a signature Smartwool logo across the chest

Unlock Your Performance Potential: Our engineered, hybrid Merino Sport 15o fabric combines the moisture management, temperature regulation, and odor resistance of Merino with the durability and quick dry time of polyester

TOP-CHOICE BASELAYER FOR OUTDOOR ACTIVITIES: Designed for high-intensity training in both mild and cold winter conditions, the Active Extreme X ¼ Zip long sleeve baselayer top has an ergonomic fit with flatlock seams to follow your body movements to a ‘T.’ It’s your “can’t-leave-home-without-it” partner for outdoor training.

BREATHABLE & INNOVATIVE: Combines SEAQUAL polyester, Coolmax Air Technology material and recycled polyester for maximum temperature control. The baselayer’s channel-knitted design provides a snug fit for warmth when you need it, while mesh inserts enhance ventilation and moisture transport.

FUNCTIONAL, NORDIC PERFORMANCE: Your new favorite active baselayer meets the highest standards of quality used by world champions and everyday heroes both. Pull on our long-sleeve, half-zip design and watch how quickly it elevates your game. Try layering during colder conditions and wearing alone at the change of seasons.

NORDIC PERFORMANCE: Designed in Sweden - a land blessed with 200 days of challenging conditions. Our highly functional Active Intensity Crewneck Longsleeve is built for dedicated athletes who work out with a purpose.

INNOVATIVE: Keeps you dry and comfortable during intensive training in medium cold to cold temperatures.

FUNCTIONAL: Stretchy, soft material with seamless construction, zone-adapted design and ergonomic fit provides optimal temperature control.

NORDIC PERFORMANCE: Designed in Sweden - a land blessed with 200 days of challenging conditions.

ATHLETIC FIT: This 3D-knit baselayer long sleeve top features a brushed inside, seamless torso, few seams, and a bodymapped design fits close to your body keeping you warm and dry.

ULTRA WARM: Lightweight and warming thermal yarn provide optimal thermoregulation. Plus, extra insulation where you need extra warmth.

NORDIC PERFORMANCE: Designed in Sweden - a land blessed with 200 days of challenging conditions. Our highly functional CORE Beat Thermal Midlayer is built for dedicated athletes who work out with a purpose.

VERSATILE: Perfect as outerwear during cool workouts or as an intermediate layer when its really cold.

BREATHABLE: Zipper at the neck for extra ventilation and easy on and off.