Update your browser for a better shopping experience!

Get faster load times, stronger security and access to all features.

M&S

Heatgen™ Maximum Thermal Long Johns

£28

Colour

Size

Also available in: Long Sleeve Top 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 (653)

4.7

74% Recommended this product

Mentions
18 January 2026Ricardian
Verified Purchase

Excellent!

Yes, I recommend this

Well made and very comfortable. Would definitely buy again.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

18 January 2026Tadpole40
Verified Purchase

Very comfortable to wear

Yes, I recommend this

Great quality thermals that are warm, fantastic for the chilly Winter months. I could recommend this product if you feel the cold. They wash well, I have bought them in the past and would buy again.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

17 January 2026Rosie2step
Verified Purchase

Disappointed

No, I don't recommend this

Bought to give added warmth for my 91 year old husband but he says they’re no warmer than the ones he already has which aren’t thermal

Helpful?

15 January 2026C4D4149
Verified Purchase

Good &Bad

No, I don't recommend this

They were supposed to be size 38waist 31leg but they were much too tight I couldn’t even do them up the other trousers were a perfect fit

Helpful?

15 January 2026Bazz63
Verified Purchase

Highly recommend for all ages!

Yes, I recommend this

Bought for my son, who works outside throughout the night. With the recent dip in temperatures he was really suffering with the cold. They have made a huge difference to how he feels and he is planning on buying more. . Very comfortable and keep him warm.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

14 January 2026Maff1
Verified Purchase

Warm and comfy

Bought for my husband, he loves them. They are quite thick, but not too thick to fit perfectly under clothes. Definitely would buy again.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

14 January 2026old man in a warm shirt
Verified Purchase

Amazing !

Yes, I recommend this

Excellent for the cold weather but it has to be cold to be comfortable

Reviewer Ratings

Comfort

Good

Helpful?

Reviewer Ratings

Comfort

Good

13 January 2026Natasha 25
Verified Purchase

Helps to keep the heating off!

Yes, I recommend this

Significantly warmer than the medium version so battles with my husband about the heating are less when he wears these ones! Soft and comfortable for him too.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

12 January 2026GARNO
Verified Purchase

Comfortable

Comfortable and warm. Good size and fits well under trousers.

Helpful?

12 January 2026Choosie buyer
Verified Purchase

Keep warm

Yes, I recommend this

Very light to wear plus very warm and cosy to wear.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

12 January 2026Outlooker
Verified Purchase

Good buy

Yes, I recommend this

Nice soft material and good fit lovely soft elastic to waist band and lovely and warm

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

11 January 2026DebbieNW
Verified Purchase

Warm

Yes, I recommend this

Bought for my husband for golfing in the cold weather and he loves them so much he’s worn them when it’s been really cold too. Super comfy and lightweight but keep his body at the right temperature.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

11 January 2026Linda FS
Verified Purchase

Great quality

Yes, I recommend this

Bought this as a gift for someone and they are very happy with the quality and warmth of the material. I think it is great value for the price.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

11 January 2026Jam6263
Verified Purchase

Nice and warm

Yes, I recommend this

Good quality and very warm. No seams in the “wrong” places to chaff. The body comes a little short so can cause cold patches around the lower back area. A longer top covers this so not that bad.

Reviewer Ratings

Comfort

Good

Helpful?

Reviewer Ratings

Comfort

Good

10 January 2026Valerie S
Verified Purchase

Warm and comfy

Yes, I recommend this

Bought for my husband. He has some by another make but rates these as being warmer.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

09 January 2026Pearciebignose
Verified Purchase

Lovely and warm

Yes, I recommend this

Great product, lovely and warm and good price - happy husband!

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

07 January 2026Fusion1
Verified Purchase

Does what it says fits well true to size

Yes, I recommend this

Buy this product for my son in law for his job he tells me they keep him warm on site

Helpful?

05 January 2026
Verified Purchase

Good.

Yes, I recommend this

Neede in this cold weather. With the wool content.

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

03 January 2026MC1156
Verified Purchase

Do keep you warm.

Yes, I recommend this

Definitely keep you warm,but pricey in my opinion.

Reviewer Ratings

Comfort

Average

Helpful?

Reviewer Ratings

Comfort

Average

01 January 2026Jagga1
Verified Purchase

So Warm!

These thermals are so soft and warm. I buy a pair of thermals every year and am never disappointed! Love them..

Reviewer Ratings

Comfort

Excellent

Helpful?

Reviewer Ratings

Comfort

Excellent

1 of 109