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Long Underwear

11 reviews

Meet the ideal base layer for sub-zero temps. Made from our custom blend of Merino wool, nylon and spandex, our long-underwear will keep you warm, comfortable and dry through winter’s coldest days and excursions.

Sizing Guide

Sizing Chart

  • In Inches
  • In CM
S M L XL XXL
Neck 14-14.535.5-37 15-15.538-39.25 16-16.540.5-42 17-17.543-44.5 18-18.545.75-47
Chest 37-3894-96.5 39-4099-101.5 41-42104-106.5 43-44109-112 45-46114.5-117
Waist 31-3279-81 33-3484-86.5 35-3689-91.5 37-3894-96.5 39-4099-101.5
Sleeve Length 32-3381-84 33-3484-86.5 34-3586.5-89 35-3689-91.5 36-3791.5-94

Looking for Tall sizes?

How to Measure

Unbound How To
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FREE shipping & returns in the US
FREE shipping in Canada
30-Day Money Back Guarantee
Details
    Technical Info
    Care Instructions
    Shipping and returns

    Shipping and Returns

    Shipping Info

    USA
    USPS: 7-9 business days - Free shipping
    DHL:  1-3 business days

    Canada
    Canada Post: 3-7 business days - Free shipping

    International
    Standard: 7-14 business days
    DHL: 2-6 business days

    *All times include handling time


    Full refund or exchange within 90 days

    You can return clothing that you purchased directly from unboundmerino.com as long as it is unworn, unwashed, and in the original condition in which it was delivered. We are happy to offer a full refund or exchange for any reason within 90 days from the ship date.

    Please visit http://returns.unboundmerino.com/ to begin your return or exchange.
    • Exchanges are subject to availability. A refund will be processed if the product you requested is unavailable.
    • Please note that all socks and underwear are FINAL SALE and can not be returned or exchanged for sanitary reasons.
    If you have any questions, get in touch by emailing help@unboundmerino.com

    As featured in

    Incredible Warmth. Total Comfort.

    • Odor-resistant and antibacterial.
    • Less washing with antibacterial clothing that stays dry, clean and fresh.
    • Dries really fast, keeping you comfortable.
    • Performs better than cotton and synthetics.
    • Tag-free band to prevent rubbing.
    Incredible Warmth. Total Comfort.

    Nature's Miracle Fabric

    Every Merino wool fiber has a waxy coating called Lanolin, which helps wick moisture away from your body, and act as a safeguard against odor-causing bacteria. This is what allows our Merino to stay breathable and dry while smelling and feeling fresh, no matter what you put it through.

    Softer than Cotton

    This wool isn’t like your typical itchy sweater. We only use superfine (17.5 micron) Merino wool, resulting in a luxuriously silky soft, underwear that’s lighter and much softer than the average Merino or cotton underwear. It'll also maintain its form over time and not get ruined after a wash, like most clothes these days. Learn more about the benefits of Merino Wool
    Natural airflow

    Natural airflow

    With Merino, your body heat can pass through the space between our woven superfine fibers, regulating your body temperature and keeping you cool & comfortable.
    ENHANCED DURABILITY

    ENHANCED DURABILITY

    When designing our long underwear, we went the extra step of blending each Merino fiber with Nylon and Spandex for extra durability and stretch. You'll also find a tag-free, ultra-soft waistband that prevents irritation--definitely a plus for long treks. This is Merino wool underwear designed to take you places.
    Perfect for Travel

    Perfect for Travel

    With underwear that don’t smell after every use, you’ll only need to pack just a few on your next trip. Wear one pair while you let the other two air out. They’ll be good as new the following day. Should one need a proper wash, a quick hand wash and air-dry and you’re good to go.

    About our Wool

    • Sustainably sourced from independent, cruelty-free wool farms in Australia.
    • Woolmark® certified Merino, adheres to the highest standards related to fibre content, performance, color fastness and dimensional stability.
    • RWS (Responsible Wool Standard) certified, adheres to the welfare of the sheep and their land.
    • WRAP (Worldwide Responsible Accredited Production) certified production.
    • Tested to ensure our clothing stands up to the rigors of travel and continual use.
    About our Wool About our Wool

    Easy Care

    You won’t have to wash the long underwear much at all. However, when it comes time for a refresh, simply add it to your load at the normal or cool temperature setting and then lay flat to dry.

    Rocking my Unbound Merino V-neck… having an every-day outfit I feel good in reduces cognitive fatigue and allows me to put all my focus on the people I love and the things I want to accomplish.

    – Jon G.
    Jon G.

    There was no way I could have possibly traveled as lightly as I did without my Unbound Merino gear. I still can’t believe that these clothes feel so good and really don’t smell after so many days worn consecutively; it’s just awesome.

    – Eric
    Eric

    Unbound Merino performs as promised, and has totally simplified how I pack when I travel the world. The shirts are AWESOME and the underwear feels like having your balls cradled by the hands of angels.

    – James “Iron Cowboy” Lawrence
    World record-setting Ironman Triathlete
    James “Iron Cowboy” Lawrence<br>World record-setting Ironman Triathlete

    I’ve worn the Unbound Merino t-shirt for most of the 18 days I’ve been travelling through Hong Kong and Thailand. Super impressed that this shirt does as promised, it doesn’t smell at all despite no washing for 18 days!

    – Ken
    Ken

    12 days backpacking with same t-shirt & still fresh! @UnboundMerino really came through with their kit.

    – Efi
    Efi
    WHAT'S INCLUDED
    Merino Wool T-Shirt
    V-Neck T-Shirt
    Boxer Briefs
    Merino Wool Socks
    Merino Wool Crew Socks
    Pocket Tank Top
    Compact Travel Hoodie
    Long Sleeve
    Raglan Crew Sweatshirt
    Women's Merino T-Shirt
    Classic Button-Down
    Merino/Polyester T-Shirt
    Essential Shorts
    Merino Crew Neck T-shirt - 175
    Merino Beanie
    Long Underwear
    Polo
    Merino Wool T-Shirt
    Merino Wool T-Shirt
    • Moisture wicking
    • Odor resistant
    • Antibacterial
    • Anti-wrinkle
    • Core Temperature Control
    • Reinforced stitching
    • 100% ultra-fine 17.5 micron, 190g/m2 Merino wool
  • 100% Merino wool jersey
  • Ultra-fine 17.5 micron
  • 190g/m2
  • Wash in normal to cool temperature setting.
  • Lay flat to dry.
  • Do not tumble dry.
  • Odor resistant
  • Fast drying
  • Anti-wrinkle
  • Temperature regulating
  • V-Neck T-Shirt
    Merino Wool T-Shirt
    • Moisture wicking
    • Odor resistant
    • Antibacterial
    • Anti-wrinkle
    • Core Temperature Control
    • Reinforced stitching
    • 100% ultra-fine 17.5 micron, 190g/m2 Merino wool
  • 100% Merino wool jersey
  • Ultra-fine 17.5 micron
  • 190g/m2
  • Wash in normal to cool temperature setting.
  • Lay flat to dry.
  • Do not tumble dry.
  • Odor resistant
  • Fast drying
  • Anti-wrinkle
  • Temperature regulating
  • Boxer Briefs
    Merino Wool Boxer Briefs
    • Reinforced stitching
    • Comfort stretch band
    • Moisture wicking
    • Odor resistant
    • Antibacterial
    • 84% Merino wool, 12% nylon and 4% spandex
  • 84% Merino wool, 12% nylon and 4% spandex
  • Ultra-fine 18.5 micron
  • 180g/m2
  • Woven elastic waistband
  • Wash in normal to cool temperature setting.
  • Tumble dry low.
  • Odor resistant
  • Fast drying
  • Anti-wrinkle
  • Temperature regulating
  • Merino Wool Socks
    Merino Wool Socks
    • One-Size-Fits-All for foot sizes 6 to 13
    • Made with a custom blend of Merino Wool (68%), Nylon (29%) and Lycra Spandex (3%) for comfort and durability
    • Odor resistant
    • Antibacterial
    • Core Temperature Control
    • Breathable vents
  • Made with a custom blend of Merino Wool (68%), Nylon (29%) and Lycra Spandex (3%) for comfort and durability
  • Wash in normal to cool temperature setting.
  • Tumble dry low.
  • Odor resistant
  • Fast drying
  • Anti-wrinkle
  • Temperature regulating
  • Merino Wool Crew Socks
    Merino Wool Crew Socks
    • One-Size-Fits-All for foot sizes 6 to 13
    • Made with a custom blend of Merino Wool (64%), Nylon (31%) and Lycra Spandex (5%) for comfort and durability
    • Odor resistant
    • Antibacterial
    • Core Temperature Control
    • Breathable vents
  • Made with a custom blend of Merino Wool (64%), Nylon (31%) and Lycra Spandex (5%) for comfort and durability
  • Wash in normal to cool temperature setting.
  • Tumble dry low.
  • Odor resistant
  • Fast drying
  • Anti-wrinkle
  • Temperature regulating
  • Pocket Tank Top
    Pocket Tank Top
    • Moisture wicking
    • Odor resistant
    • Antibacterial
    • Anti-wrinkle
    • Core Temperature Control
    • Reinforced stitching
    • 100% ultra-fine 17.5 micron, 190g/m2 Merino wool
  • 100% Merino wool jersey
  • Ultra-fine 17.5 micron
  • 190g/m2
  • Odor resistant
  • Fast drying
  • Anti-wrinkle
  • Temperature regulating
  • Compact Travel Hoodie
    Compact Travel Hoodie
    • Odor resistant
    • Temperature regulating
    • Moisture wicking
    • Seamless pockets
    • Sleek black YKK inverted zipper
    • 97% ultra-fine Merino wool / 3% elastane for durability and stretch
    • 21.5 micron / 250 GSM
  • 97% ultra-fine Merino wool / 3% elastane for durability and stretch
  • 21.5 micron
  • 250 GSM
  • Matte black pull tab with sleek
  • inverted zipper
  • Seamless pockets
  • Wash in normal to cool temperature setting.
  • Lay flat to dry.
  • Do not tumble dry.
  • Light and breathable
  • Odor resistant
  • Fast drying
  • Anti-wrinkle
  • Temperature regulating
  • Long Sleeve
    Long Sleeve
    • Moisture wicking
    • Odor resistant
    • Antibacterial
    • Anti-wrinkle
    • Core Temperature Control
    • Reinforced stitching
    • 100% ultra-fine 17.5 micron, 190g/m2 Merino wool
  • 100% Merino wool jersey
  • Ultra-fine 17.5 micron
  • 190g/m2
  • Wash in normal to cool temperature setting.
  • Lay flat to dry.
  • Do not tumble dry.
  • Odor resistant
  • Fast drying
  • Anti-wrinkle
  • Temperature regulating
  • Raglan Crew Sweatshirt
    Raglan Crew Sweatshirt
    • Odor resistant
    • Temperature regulating
    • Moisture wicking
    • French terry interior for softness and comfort
    • 97% lightweight ultra-fine Merino wool for light packing and breathability
    • 3% elastane added for durability and stretch
    • 21.5 micron / 250 GSM
  • 97% lightweight ultra-fine Merino wool for light packing and breathability
  • 3% elastane added for durability and stretch
  • 21.5 micron
  • 250 GSM
  • Wash in normal to cool temperature setting.
  • Lay flat to dry.
  • Do not tumble dry.
  • Light and breathable
  • Odor resistant
  • Fast drying
  • Anti-wrinkle
  • Temperature regulating
  • Women's Merino T-Shirt
    Women's Merino T-Shirt
    • Moisture wicking
    • Odor resistant
    • Antibacterial
    • Anti-wrinkle
    • Core Temperature Control
    • Reinforced stitching
    • 100% ultra-fine 17.5 micron, 190g/m2 Merino wool
    Classic Button-Down
    Classic Button-Down
    • Odor resistant
    • Light and breathable
    • Fast drying
    • 54% premium Merino wool
    • 46% organic cotton
    • 146gsm
    • Cross-woven for breathability
  • 54% Merino wool, 46% organic cotton
  • 146gsm
  • Cross-woven for breathability
  • Wash in cool temperature setting.
  • Hang to dry.
  • Light and breathable
  • Odor resistant
  • Fast drying
  • Wrinkle resistant
  • Perfect for packing
  • Merino/Polyester T-Shirt
    • Antibacterial
    • Moisture wicking
    • Odor resistant
    • Anti-wrinkle
    • Core Temperature Control
    • Ultra-fine 17.5 micron Merino/Poly blend
    • 56% Merino, 44% Polyester - 190g/m2
  • 56% Merino, 44% Polyester
  • 17.5 micron
  • 190g/m2
  • Wash in normal to cool temperature setting.
  • Lay flat to dry.
  • Do not tumble dry.
  • Odor resistant
  • Fast drying
  • Anti-wrinkle
  • Temperature regulating
  • Essential Shorts
    Essential Shorts
    • Anti-wrinkle
    • Water Repellent
    • Hidden Back Zipper Pocket
    • 2-way Comfort Stretch
    • 48% Merino wool, 48% Cotton, 4% Spandex
    • 8 1/2" inseam length
  • 48% Merino wool, 48% Cotton, 4% Spandex
  • 8 1/2" inseam length
  • Wash in cool temperature setting.
  • Hang or lay flat to dry.
  • Do not tumble dry.
  • Anti-wrinkle
  • Water repellent
  • 2-way comfort stretch
  • Odor resistant
  • Merino Crew Neck T-shirt - 175
    Merino Wool T-Shirt
    • Moisture wicking
    • Odor resistant
    • Antibacterial
    • Anti-wrinkle
    • Core Temperature Control
    • Reinforced stitching
    • 100% ultra-fine 17.5 micron, 175g/m2 Merino wool
    • 100% Merino wool jersey
    • Ultra-fine 17.5 micron
    • 100% ultra-fine 17.5 micron, 175g/m2 Merino wool
  • Wash in normal to cool temperature setting.
  • Lay flat to dry.
  • Do not tumble dry.
  • Odor resistant
  • Fast drying
  • Anti-wrinkle
  • Temperature regulating
  • Merino Beanie
    Merino Beanie
    • 2X2 Rib
    • 7 Gauge Knit
    • Naturally Antibacterial
    • Rolled Brim
    • Moisture Wicking
    • 100% Italian Spun Merino Wool
    • Made in Canada
  • 100% Italian Merino wool
  • 2x2 rib
  • 7 gauge knit
  • Rolled brim
  • Dry clean only.
  • Anti-bacterial
  • Fast drying
  • Temperature regulating
  • Long Underwear
    Merino Wool Long Underwear
    • Reinforced stitching
    • Comfort stretch band
    • Moisture wicking
    • Odor resistant
    • Antibacterial
    • 84% Merino wool, 12% nylon and 4% spandex
    • Inseam length: 28 inches
  • 84% Merino wool, 12% nylon and 4% spandex
  • Ultra-fine 18.5 micron
  • 180g/m2
  • Inseam length: 28 inches
  • Woven elastic waistband
  • Wash in normal to cool temperature setting.
  • Tumble dry low.
  • Odor resistant
  • Fast drying
  • Anti-wrinkle
  • Temperature regulating
  • Polo
    Merino Wool Polo
    • Moisture wicking
    • Odor resistant
    • Antibacterial
    • Anti-wrinkle
    • Core Temperature Control
    • Reinforced stitching
    • 53% Merino 47% polyester double knit
    • Mother of Pearl Buttons
  • 53% superfine Merino wool, 47% Polyester
  • 165g/m2
  • Clean finished back yoke w/ pleats
  • Mother of Pearl Buttons
  • 1/2 Placket
  • Wash in normal to cool temperature setting.
  • Lay flat to dry.
  • Do not tumble dry.
  • Odor resistant
  • Fast drying
  • Anti-wrinkle
  • Temperature regulating
  • What People Are Saying

    Customer Reviews
    4.8 Based on 11 Reviews
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    • Reviews
    • Questions

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    Your input is very much appreciated. Share it with your friends so they can enjoy it too!

    Filter Reviews:
    KK
    02/15/2021
    kamran k.
    United States United States
    Great long underwear

    Great product- used it while skiing as a first layer and worked really well to keep me warm

    RS
    02/09/2021
    Richard S.
    United States United States
    Nice warm material

    Fits really well and seems durable

    • How did you find the fit? Runs SmallSlightly SmallTrue To SizeSlightly BigRuns Big
    SR
    01/12/2021
    Sanjay R.
    United States United States
    Long underwear

    It's a snug fit. Almost could double for training leggings to work out in. Not quite as warm as I'd expect so don't wear it by itself if you were expecting full on thermals. Works with a pair of shorts for outdoor use too.

    • How did you find the fit? Runs SmallSlightly SmallTrue To SizeSlightly BigRuns Big
    RT
    01/04/2021
    Robyn T.
    United States United States
    Great!

    They are excellent as pajamas. Just the right weight and super comfortable.

    • How did you find the fit? Runs SmallSlightly SmallTrue To SizeSlightly BigRuns Big
    CA
    01/01/2021
    Charles A.
    United States United States
    Usual Stuff From Unbound

    What's usual? Fits, feels good, doesn't smell after 2 days, looks good. I have everything from Tee Shirts through Crews, Sweatshirts to Long Underwear... all right on!!

    • How did you find the fit? Runs SmallSlightly SmallTrue To SizeSlightly BigRuns Big