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2 Pack Heatgen™ Light Thermal Long Johns

Product code: T149483

About this style

For cold-weather comfort, these lightweight thermal underwear long johns provide warmth without bulk. Cut to a regular fit for easy movement, with soft seams for comfort. Heatsealed care labels ensure all-day comfort. Heatgen™ technology helps your body stay warm by generating and retaining heat. A practical fly front fastening completes this functional layering item. M&S Collection: Easy-to-wear wardrobe staples that combine classic and contemporary styles.

Light warmth for cooler conditions and everyday comfort.

Details & care

Style

Regular fit

Fly front fastening

Added stretch

Features

Heatgen™ technology

lightweight and supersoft, designed to keep you warm when the weather gets chilly

Composition

38% acrylic, 29% cotton, 29% viscose and 4% elastane lycra® (exclusive of trimmings), Ribbing - 39% acrylic, 30% cotton, 29% viscose and 2% elastane

Care

Wash at 40°C

Do not bleach

Tumble dry low temperature

Iron at medium temperature

Do not dry clean

M&S

2 Pack Heatgen™ Light Thermal Long Johns

£28

Colour

Size

Also available in: Long Sleeve and Short Sleeve
Free standard delivery over £75

Reviews (602)

4.6

67% Recommended this product

Mentions
02 June 2026Matthew8888
Verified Purchase

Shonky Sizing

No, I don't recommend this

The size is supposed to be a medium but it’s definitely a large. And it’s underwear so it cannot be returned/exchanged.

Reviewer Ratings

Comfort

Fair

Helpful?

Reviewer Ratings

Comfort

Fair

01 June 2026Maryn47
Verified Purchase

Good for extra layer

Yes, I recommend this

Husband who has Alzheimers feels the cold and these give an extra layer. However I do hope they last a bit better than previous ones which kept parting from the waist band

Reviewer Ratings

Comfort

Good

Helpful?

Reviewer Ratings

Comfort

Good

01 June 2026Avo67
Verified Purchase

Good value

Yes, I recommend this

Bought as replacement for my 90 yr old dad who likes his thermal underwear all year round. Always wash well and perfect fit for him

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

21 April 2026Sissy55
Verified Purchase

Good fit!

Bought for my husband, who is happy with the fit. Unable to test them until later in the year when we go skiing.

Helpful?

07 April 2026Rob Highgate
Verified Purchase

Hurrah - no button!

Yes, I recommend this

Fly front, so no annoying miniature button. And a good leg length too. Pleased!

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

29 March 2026AngieDC
Verified Purchase

Lightweight and soft

My hubby loves these. Light enough to wear indoors, good fit and wash well

Helpful?

16 March 2026dwarfie
Verified Purchase

Great quality and good value.

Bought these for my husband to wear under walking trousers. He is delighted with them and pleasantly surprised at the quality as they were inexpensive.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

12 March 2026Jo JH
Verified Purchase

Comfortable

Yes, I recommend this

Very comfortable, slightly big but kept me warm, prefer the men’s as they come up to my waist

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

11 March 2026Trampus94
Verified Purchase

Toasty warm

Yes, I recommend this

Excellent base layers, kept me nice and warm when outside in the evening on the petanque terrain.

Helpful?

08 March 2026Happy Eva After
Verified Purchase

Fantastic quality

Yes, I recommend this

My husband LOVES these! Lightweight but warm, wash really well and dry without bobbling.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

05 March 2026Jim697
Verified Purchase

Good quality

Just what I’m needed to keep me warm. Good colour and texture

Reviewer Ratings

Comfort

Good

Helpful?

Reviewer Ratings

Comfort

Good

06 February 2026lisa9003
Verified Purchase

Very warm and comfortable

Yes, I recommend this

Great product ... kept us warm in -18 and not too think to wear under jeans

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

04 February 2026WorkingMum1000
Verified Purchase

good quality and price

Yes, I recommend this

Bought these for my husband-add warmth with out bulk at a good price

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

31 January 2026Nickyj1
Verified Purchase

Great quality

Yes, I recommend this

Perfect fit great breathable fabric nice and soft with a good stretch

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

30 January 2026KimFH
Verified Purchase

Good quality and comfortable

The product is good quality and comfortable providing warmth in the Scottish winter!

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

29 January 2026standsoutside
Verified Purchase

Good quality and value

Yes, I recommend this

My husband likes this thermal underwear. He prefers them to the heavier weight ones as they are a closer fit and keep him warm. I think they must be quite stretchy as he is a 40” waist and the Medium fit well. They also wash well and dry quickly.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

27 January 2026mikkim
Verified Purchase

Excellent product

My husband finds that the long john's are perfect for the cold weather . They keep him nice and warm .

Helpful?

26 January 2026AshleyP
Verified Purchase

Comfortable and warm

Yes, I recommend this

Silky, soft material with enough stretch to adjust easily for movement and provide warmth for those with cold legs. Does not ride up like shorter pants, even when sat on soft furnishings. Gusset is convenient yet secure. Ideal winter wear indoors or out.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

24 January 2026Billy555
Verified Purchase

Great quality, good price

Yes, I recommend this

I have purchased these before. These performed great so I came back for more.

Helpful?

22 January 2026Ajwb
Verified Purchase

Keeping warm

Yes, I recommend this

Bought these for my husband as he spends a lot of time outdoors he loves them keeps him very warm

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

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