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M&S

Heatgen™ Maximum Thermal Long Johns

£28

Colour

Size

Also available in: Long Johns and Vest
Free standard delivery over £60

Product code: T147412W

About this style

These thermal long johns combine warmth with comfort through our warming Heatgen™ fabric. Cut to a regular fit with an elasticated waist and cuffed bottoms for secure, comfortable wear. The base layer underwear keeps you warm throughout the day, while the brushback texture feels gentle on skin. Supersoft seams prevent chafing, and a keyhole fly adds everyday practicality. Perfect cold weather clothing for when temperatures drop. M&S Collection: Easy-to-wear wardrobe staples that combine classic and contemporary styles.

Maximum warmth for keeping cosy in colder climates.

Details & care

Style

Regular fit

Features

Thermal

Soft and cosy brushed fabric that keeps warmth in

Heatgen™ technology

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

Composition

35% wool, 26% polyester, 23% viscose and 16% polyamide (exclusive of trimmings)

Care

Wash at 40°C

Do not bleach

Tumble dry medium temperature

Iron at low 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 (610)

4.7

73% Recommended this product

Mentions
06 November 2025BP97
Verified Purchase

Warm

Yes, I recommend this

Nice and warmer purchased to wear while riding motorcycle although they were on the pricey side

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

06 November 2025J2341
Verified Purchase

Great quality and comfortable.

Great quality and very comfortable. Ideal for winter weather

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

03 November 2025Poiuytr66
Verified Purchase

Good quality

Good quality, very comfortable/fit would recommend.

Helpful?

02 November 2025David 2
Verified Purchase

Keeps you warm

Yes, I recommend this

Comfortable and noticeably warmer than the "warm" ones.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

02 November 2025ReazonsB84
Verified Purchase

Everything I expect from M&S

Yes, I recommend this

Great quality and style and a price you would expect

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

29 October 2025keeplooking
Verified Purchase

Very useful buy

Yes, I recommend this

Warm and comfortable for longer periods outdoors in cooler weather.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

20 October 2025Jane N Wales
Verified Purchase

Would recommend

Yes, I recommend this

Good quality, wash well. Bought these for my husband as visiting -7 degree country and they performed well. Kept him very warm. Good value compared with those found in outdoor/hiking shops.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

20 October 2025AL Kent
Verified Purchase

Reliable

Yes, I recommend this

I’ve been satisfactorily using M&S thermal garments for several years. Recently bought these Heatgen Max which are really good, great comfort, great fit, very effective

Helpful?

17 October 2025Royle09
Verified Purchase

Toasty

Yes, I recommend this

These bottoms keep you really toasty Very soft you don't even know your wearing them. Would highly recommend this item for the winter days.

Helpful?

09 October 2025LABCBLUE
Verified Purchase

Amazing Quality

Yes, I recommend this

First time I’ve purchased Long Johns, preparing for winter golf! They are fantastic and really do the job. I would also say that I was surprised that the quality of the garment is so good.

Helpful?

03 October 2025Maggie M 22
Verified Purchase

A big hit in USA!!!

Yes, I recommend this

Unable to write proper review as bought these for Xmas presi for elderly brother in USA! He requested them especially as they are such amazing value! ( He buys them every winter!!).Can’t get anything of this quality & this price in USA he says!

Helpful?

26 September 2025Andrea W
Verified Purchase

A winter staple. Ideal Xmas present

Yes, I recommend this

I buy these every year for a friend. So warm and where so well

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

23 September 2025Paul L W
Verified Purchase

Must have winter basic.

Yes, I recommend this

Great fit and sure to be perfect for the winter season.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

13 April 2025Johnenigma
Verified Purchase

Thermals

Yes, I recommend this

Look and feel very good. Much thicker than other M&S thermals I have. Bought ready for next winter, so not worn them yet.

Reviewer Ratings

Quality

Excellent

Value for Money

Good

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Good

08 April 2025Oluyemi
Verified Purchase

Very good material

Yes, I recommend this

The material is quality and very good not hitching. I love it.

Reviewer Ratings

Value for Money

Excellent

Style

Excellent

How did it fit?

True to size

Helpful?

Reviewer Ratings

Value for Money

Excellent

Style

Excellent

How did it fit?

True to size

07 April 2025Paddlin
Verified Purchase

Very good product.

Yes, I recommend this

Very good product. My husband feels the cold terribly and these are just the job for keeping his legs warm.

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How did it fit?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How did it fit?

True to size

02 April 2025JCH59
Verified Purchase

Great quality

Yes, I recommend this

Great thermals I use them often especially on my bike

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

How did it fit?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

How did it fit?

True to size

13 March 2025SamSteve
Verified Purchase

Amazing Long Johns

Yes, I recommend this

Brilliant warm long johns. Partner a builder and they kept him warm under his work jeans

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How did it fit?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How did it fit?

True to size

12 March 2025MrsJAC
Verified Purchase

Excellent value and warmth

Yes, I recommend this

Everyone who I bought these for was really pleased!

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How did it fit?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How did it fit?

True to size

12 March 2025Alison Scotland
Verified Purchase

Very warm

Yes, I recommend this

Bought for my husband who is a diver and le loves them

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Fair

How did it fit?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Fair

How did it fit?

True to size

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