250 GSM is our everyday cold-weather standard — warm enough for winter city days, breathable enough for the trail.
Fabric weight guide
Which merino weight is right for you?
GSM is grams per square metre — how much fabric there is, not a warmth rating. Every weight is the same soft 17.5-micron Australian merino: it wicks sweat before it turns cold, insulates when it is cold and ventilates when it is warm. Lighter fabric breathes and dries faster; heavier fabric holds more heat when you stop moving. Choose by season and by how hard you will be working.
Warm & hot · 60°F+ / 15°C+
Best for: summer hiking, running, cycling, hot-climate travel, everyday tees and office wear; the next-to-skin layer under a 250 when you work hard in winter
Pick this if: you want a shirt that stays fresh for days, dries in an hour and keeps you cooler than cotton in the heat — or you simply run hot
Think twice if: you will mostly be standing still in the cold; on its own a lightweight layer has little insulation to offer
Shop 165 GSM →Cool to mild · 40–65°F / 5–18°C
Best for: spring and autumn as a standalone top, summer evenings, cool-morning hikes and commutes; winter as a base under a mid-layer
Pick this if: you want one merino layer that covers most of the year, or you are unsure between light and mid — this is where most people should start
Think twice if: you run cold and your winter is genuinely cold: go straight to 250
Shop 190 GSM →Cold · 20–45°F / −7 to 7°C
Best for: skiing and snowboarding, winter hiking, cold-weather work, frosty autumn mornings; top-and-bottom sets so your legs are not the weak link
Pick this if: you run cold in fall, want the classic winter base layer, or spend active days below freezing under a shell
Think twice if: you overheat easily on hard uphill efforts — a 165 or 190 underneath, 250 over it, is the better system
Shop 250 GSM →Deep cold · below 20°F / −7°C
Best for: ice fishing, hunting stands, camp at altitude, winter mornings spent waiting rather than walking, a house that never quite gets warm
Pick this if: warmth matters more than breathability, you are chronically cold, or your winter involves long spells standing still outdoors
Think twice if: you will be working hard — it is too warm for a sweaty climb, which is exactly the point
Shop 320 GSM →A base layer works by sitting close to the skin, where it can move moisture — loose is not more comfortable, just slower. Between sizes? Size down for a next-to-skin layer under a shell, size up to wear it on its own or over another layer. Merino stretches with wear and springs back after a wash. Heavier weight is not itchier: itch comes from coarse fibre, and every weight here is the same superfine merino.
Size guide
Size Guide
Our merino has a close, next-to-skin fit by design. If you are between sizes, stay true to size for base-layer use or size up for a more relaxed everyday fit. Free returns within 30 days, so ordering two sizes and sending one back is completely fine.
How to measure
Chest — around the fullest part of your chest, with the tape level under the arms.
Waist — around your natural waistline, with the tape comfortably loose.
Hips — around the fullest part of your hips and seat.
Inside leg — from the top of your inner thigh to your ankle bone.
Measure over light clothing, keeping the tape snug but not tight. Tap any chart below to open it full size.
Men's Base Layer Set
Need different sizes for the top and the bottoms? Build your own set →
Women's Base Layer Set
Need different sizes for the top and the bottoms? Build your own set →
Kids' Base Layer Set
Men's T-Shirt
Women's T-Shirt
Men's Long Sleeve
Same body measurements across 165, 190, 250 and 320gsm.
Women's Long Sleeve
Kids' Long Sleeve
Men's Long Johns
Women's Thermal Leggings
Kids' Thermal Leggings
Men's Half Zip
Women's Half Zip
Merino Wool Socks
Beanies, snoods and balaclavas
Still unsure which size to pick? Email info@merinotech.co.uk with your height, chest and waist and we will recommend a size. Free UK delivery over £49 and free returns within 30 days.
- Free UK delivery over £49
- 30-day free returns
- Ships in 1–2 business days
Description
Men's Merino Wool Thermal Set
Stay protected during skiing, snowboarding, hiking, and winter travel with this Men’s Merino Wool Thermal Set. Merino wool naturally traps warmth while remaining breathable enough for high-output activities. Moisture-wicking fibres rapidly move sweat away from the skin to maintain dry comfort on the slopes or trails. Odour-resistant properties help the fabric remain fresh after long days outdoors. Soft hypoallergenic wool provides smooth comfort without irritation or heaviness.
Stretchable elasticity improves flexibility during movement, while lightweight construction allows efficient layering. Anti-static comfort, UV protection, and eco-friendly wool fibres add long-lasting value.
Care
Turn inside out. Machine wash cold on a gentle cycle with like colours and a wool-safe detergent. Do not bleach. Lay flat or hang to dry — do not tumble dry.
Shipping & returns
Free UK delivery on orders over £49. Orders ship within 1–2 business days. 30-day free returns on unworn items with tags attached.
Men's base layer set
Top and bottom, matched and ready
Long sleeve top and pants in the same weight and colour — the fastest way to a complete cold-weather base. Flatlock seams, a soft non-itchy finish and a fit that stays close without squeezing.
Size guide
Men's Set 250
Fit
The top and the bottoms come in the same size, with a close, next-to-skin fit. Need different sizes for the top and the bottoms? Build your own set.
How to measure
- Chest – around the fullest part of your chest, tape level under the arms.
- Waist – around your natural waistline, tape comfortably loose.
- Hips – around the fullest part of your hips and seat.
- Inside leg – from the top of your inner thigh to your ankle bone.
Measure over light clothing and keep the tape snug but not tight. Still unsure? Email info@merinotech.co.uk with your height, chest and waist and we will recommend a size. Unworn items can be returned free within 30 days.
THE FABRIC
Why merino wool
Merino wool moves sweat away from your skin as vapour and lets it evaporate from the fabric, so you stay dry and comfortable whether you are hiking, commuting or skiing.
Merino fibres naturally resist the bacteria that cause odour, so you can wear a base layer for several days, on the trail or while travelling, and it still smells fresh.
Wool can absorb up to 30% of its weight in moisture without feeling wet. In damp British weather it keeps insulating where cotton and polyester leave you cold.
Merino absorbs UV radiation: our lightweight layers offer UPF 25 and the midweight and heavyweight options UPF 50+, handy on long days in the hills.
Merino wool is naturally hard to ignite and self-extinguishes without melting onto the skin, unlike synthetic base layers.
Merino is a natural, renewable and biodegradable fibre. Sheep grow a new fleece every year, and a worn-out merino garment breaks down instead of shedding plastic microfibres.
FAQ
Men's merino thermal sets: FAQ
What is this 250gsm thermal base layer set best for?
It is a midweight 250gsm merino layer, best for skiing, hiking and cold UK winters. Compare every weight in our merino weight guide.
Which sizes are in stock?
Available to order now: , S, M, L, XL, XXL, XXXL. Our merino is true to size and designed to sit close to the skin; see the size guide for measurements.
Is this thermal base layer set warm enough for skiing?
Yes. 250gsm midweight merino under a ski jacket and trousers is the most popular choice for a ski holiday. Choose 320gsm if you feel the cold.
What is included in a merino base layer set?
A long sleeve thermal top and matching long johns in the same fabric weight and colour, so your core and legs stay equally warm.
Is a set cheaper than buying the top and bottoms separately?
Yes, a set is priced below the two pieces bought individually. If you want different weights or colours for the top and bottoms, use the build your own set page.
Which merino set is best for skiing?
For most skiers in the Alps or Scotland a 250gsm midweight set is the right choice. Choose 320gsm if you feel the cold, ski in very low temperatures or spend long periods on chairlifts, and 165–200gsm for spring skiing or ski touring.
What is the advantage of a zip-up set?
The half-zip top lets you vent heat quickly on climbs or in a warm lodge without taking a layer off, then zip up again when you stop.
How do I choose the size for a set?
Top and bottoms come in the same size, which suits most people. If your top and bottom sizes differ, build your own set instead. Measurements are in the size guide.
Bought these for my son for Xmas and he just wore them for the fist time straight out of the package skiing for spring break and we discovered a rather large hole right in the middle of the shirt. This was pretty disappointing as I bought another set for myself and my youngest. So far no holes on those but again this was after 1 wear.
Bought these for my son for Xmas and he just wore them for the fist time straight out of the package skiing for spring break and we discovered a rather large hole right in the middle of the shirt. This was pretty disappointing as I bought another set for myself and my youngest. So far no holes on those but again this was after 1 wear.
I am 5.10 ft with 77 KG of weight. Size M fits really well.Still not to try how it works in Cold weather but the built quality is very good. I took 320g set and its not very thin and has some weight so I think I got what I purchased (more Wool)I am feeling some itching when wearing without any undergarments on top so I think I need to use it wearing something below.Feels like I am set for USA Winters
I am 5.10 ft with 77 KG of weight. Size M fits really well.Still not to try how it works in Cold weather but the built quality is very good. I took 320g set and its not very thin and has some weight so I think I got what I purchased (more Wool)I am feeling some itching when wearing without any undergarments on top so I think I need to use it wearing something below.Feels like I am set for USA Winters
I went with the light weight base layer set first & was very pleased. So today I ordered the mid weight base layer set. Also I noticed a review complaining about a hole in their top base layer. These products are made out of wool. Moths love wool & will eat holes in the products. You need to take care of them. I will wash mine & I place them back in the plastic bag they came in. Thank You Merino.Tech!
Feels really soft and warm. Cannot wait to take it out for skiing.
I like how this merino feel. I didn't get a chance to wash it so curios if it will remain the same.
Feels really soft and warm. Cannot wait to take it out for skiing.
I like how this merino feel. I didn't get a chance to wash it so curios if it will remain the same.
Feel great !!
Trying to get your 320g version of the top .. and bottoms (if available for colder snow conditions )
Feel great !!
Trying to get your 320g version of the top .. and bottoms (if available for colder snow conditions )
Absolutely love!
Absolutely love!
Very warm and durable
Very fadt shipping
Very warm and durable
Very fadt shipping
These are my favourite base layers by far. Both the top and bottom exceed the supreme softness and soothing cushioning of even cashmere! Putting on an outer layer just makes it better as the intoxicating comfort is increased by the outer layer squeezing it onto you. I can't recommend these highly enough, unless you detest feeling wonderful.
These are my favourite base layers by far. Both the top and bottom exceed the supreme softness and soothing cushioning of even cashmere! Putting on an outer layer just makes it better as the intoxicating comfort is increased by the outer layer squeezing it onto you. I can't recommend these highly enough, unless you detest feeling wonderful.
Men's Merino Thermal Set 250 Black
Men's Merino Thermal Set 250 Black
Excellent.
Excellent.
Soft as silk and performance as expected (I groom Nordic ski trails with this as base layer).
Soft as silk and performance as expected (I groom Nordic ski trails with this as base layer).
Happy with my prder. Was delivered packed nice, and love the free socks.
Happy with my prder. Was delivered packed nice, and love the free socks.
Material is very soft and warm. Works great as a base layer on cold days.
Material is very soft and warm. Works great as a base layer on cold days.
I love the full set of medium weight!
Three of us received them for Christas and ALL of us are happy and toasty!
