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M&S

2 Pack Heatgen™ Light Thermal Long Johns

£28

Colour

Size

Free standard delivery over £60

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

Delivery, collection & returns

Delivery

Standard

UK Standard Delivery is available for £3.99 or free on orders over £60 (excluding furniture).

Nominated Day

UK Next Day Delivery and UK Nominated Day Delivery (excluding Northern Ireland) are available for £5.99 (excluding furniture)

Collection

Collect from store

Store collection is free on all fashion, home and beauty orders.

Returns

UK returns

Free

Exclusions apply

Full delivery and collection informationOur returns policy

Reviews (590)

4.6

67% Recommended this product

Mentions
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

20 January 2026noodles231
Verified Purchase

Light yet warm

Yes, I recommend this

Good for a winter day when thicker thermals are too bulky - such as when wearing a suit

Reviewer Ratings

Comfort

Good

Helpful?

Reviewer Ratings

Comfort

Good

18 January 2026Cam32
Verified Purchase

Perfect weight for under jeans

Yes, I recommend this

Nice quality fabric. Bought for my son, legs on the long side for a 5ft 2” person. Would be nice to have a choice in length.

Reviewer Ratings

Comfort

Good

Helpful?

Reviewer Ratings

Comfort

Good

17 January 2026AmandafromTonbridge
Verified Purchase

Wouldn’t be without them

Yes, I recommend this

My son has worn these for sometime and during the recent cold snap my husband borrowed them from him. Needless to say he loved them and now has his own. Keeps you warm and washes well

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

16 January 2026Barry77
Verified Purchase

Very effective

These thermals are very effective, convenient to wear and very comfortable

Helpful?

15 January 2026KG167
Verified Purchase

Winter warmer

Yes, I recommend this

Purchased online & kept informed, collected in local store & my husband is very please with the purchase

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

15 January 2026griffgriffgriffin
Verified Purchase

Comfortable material.

Good quality material. Lightweight to wear and comfortable too. Like the colour and they are a good fit just the right fit.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

15 January 2026M B Gardens
Verified Purchase

Do the Job

Yes, I recommend this

I work outdoors and have found M&S brand thermals the best. Wear them daily in the winter tops and leggingd

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

12 January 2026LynnDotW
Verified Purchase

Does the job

Yes, I recommend this

Bought these for spouse, he says they do the job. They are comfortable

Helpful?

04 January 2026LiziBow
Verified Purchase

Good stretchy thermal leggings

Lovely stretchy cotton mix as usual love - husband loves these in the winter

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

01 January 2026Jeanie Pots
Verified Purchase

Medium to lightweight

Yes, I recommend this

These are just right for my husband to wear under jeans, not too thick but adds a warm layer

Reviewer Ratings

Comfort

Good

Helpful?

Reviewer Ratings

Comfort

Good

12 December 2025N K
Verified Purchase

Warm and nice

Yes, I recommend this

Great material and warm and lovely to wear and I like it.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

12 December 2025RugbyMark
Verified Purchase

Warm under layer

Warm but thin enough to wear under trousers without adding bulk.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

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