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M&S Collection

Heatgen™ Maximum Thermal Long Johns

€ 40

COLOURBlack
SIZE

Also available in: Long Johns and Vest
Free standard delivery over €50

Product code: T147412W

About this style

When the temperature drops, beat the chill in our thermal long johns. Regular fit with an elasticated waist and cuffed bottoms for snug and secure wear. Functional keyhole fly opening. Our clever Heatgen™ technology uses an innovative fibre blend, helping your body to generate and retain heat so you can stay warm when the weather gets chilly. Brushback texture feels gentle against your skin, while supersoft seams ensure there's no chafing.

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

FREE over €50, or €4.50

Collection

Collect from store

FREE

Returns

Ireland returns

FREE

Exclusions apply

Reviews (569)

4.7

73% Recommended this product

Mentions
2025 februar 06Halfwit

Good quality

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

These Thermals are quite good quality and are nice and warm on these cold winter days. True to size and very comfortable. The only slight complaint I have is I feel they are a bit too expensive for pensioners like me.

Reviewer Ratings

Quality

Excellent

Value for Money

Average

Style

Average

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Average

Style

Average

How do you feel about the size?

True to size

2025 februar 06Annie B Goode

Warm and comfortable

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

I'd already bought the Heatgen Maximum Thermal t-shirts for my husband and knew he was pleased with them so when he complained of having cold legs, decided to order these for him. They are the same great quality material (which includes merino wool) with a ribbed finish outside and a cosy brushed finish inside. My husband confirms that they're comfortable to wear and keep him warm. They wash well too.

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How do you feel about the size?

True to size

2025 februar 05Tori98

Nice product

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Excellent product well made perfect fit worth the Money

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Good

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Good

How do you feel about the size?

True to size

2025 februar 05H G 9

Too loose on legs , good quality

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

All came ok . Long johns not tight enough round legs , in my experience with mountain walking they need to be snug fit. P s I am not fat or skinny. Thanks

Reviewer Ratings

Quality

Good

Value for Money

Average

Style

Average

How do you feel about the size?

Very large

Helpful?

Reviewer Ratings

Quality

Good

Value for Money

Average

Style

Average

How do you feel about the size?

Very large

2025 februar 05Frankcw

Thermal underwear

Originally posted on marksandspencer.com (UK)

They seem okay but it hasn't been cold enough to wear them

Helpful?

2025 februar 04Messo53

Must have

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Great product and sooooo cosy and warm brilliant for hill walking

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

How do you feel about the size?

True to size

2025 februar 03

Best thermals on the market

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Perfect for my outside work, very snug, great fit, warm as toast.

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How do you feel about the size?

True to size

2025 februar 03Mariconchi

Great for the cold.

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Excellent. So warm in the cold weather. Very good quality.

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How do you feel about the size?

True to size

2025 februar 01Lennie97

Good quality

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Bought for my husband to wear outdoors fishing. He said it’s ideal, good quality, very comfortable and keeps him nice and warm

Reviewer Ratings

Quality

Excellent

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

How do you feel about the size?

True to size

2025 januar 30hbe66

Good thermals

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Bought for my husband who was feeling the winter cold. I assumed they would be made from the same fabric as the ladies max Heatgen version, which are brilliant, but they are quite different. However, he assures me they are very warm, comfortable and a good fit, so one satisfied customer!

Reviewer Ratings

Quality

Average

Value for Money

Fair

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Average

Value for Money

Fair

How do you feel about the size?

True to size

2025 januar 29CJBU

Nice & cosy

Originally posted on marksandspencer.com (UK)

My husband likes the fabric mix of these long johns as they’re very soft but warm and also not too baggy

Reviewer Ratings

Quality

Good

Value for Money

Good

Style

Good

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Good

Value for Money

Good

Style

Good

How do you feel about the size?

True to size

2025 januar 26Brid28

Great Quality

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Very warm and comfortable, my husband would definitely recommend.

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

How do you feel about the size?

True to size

2025 januar 26mags

Warm

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Warm , well fitting and not too long, keeps lower legs very toasty.

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

How do you feel about the size?

True to size

2025 januar 23GeoffsMum

Warm!

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

A repeat purchase. Very good quality, excellent level of warmth, soft and comfortable to wear. Great fit. Not the cheapest but you get what you pay for here.

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How do you feel about the size?

True to size

2025 januar 23Suzzie2

Soo warm!!

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Warm, soft and totally comfortable. I would certainly recommend this item.

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Excellent

How do you feel about the size?

True to size

2025 januar 21Spot20

Heatgen thermal

Originally posted on marksandspencer.com (UK)

Lovely and warm. Can wear on there own our under trousers .

Helpful?

2025 januar 21ed30

Good value for money and quality is good.

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

These were for my husband who works outside in cold weather. Fit well ,well made and very good value for money and above all keep him warm.

Reviewer Ratings

Quality

Good

Value for Money

Excellent

Style

Good

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Good

Value for Money

Excellent

Style

Good

How do you feel about the size?

True to size

2025 januar 20SeniorGolfer

Great as a base layer for golf

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Along with the vest, I bought these as a base layer for playing golf in sub-zero temperatures. My first experience was in an ambient temperature of minus 4 and feeling minus 5. After 4 holes, I was so comfortable I had to take one of the top 4 layers off, so very impressed with their thermal capacity

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Average

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

Style

Average

How do you feel about the size?

True to size

2025 januar 19Spider52

Warm and cosy leggings

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Good quality product. Sizing good and product very comfortable and warm as expected.

Reviewer Ratings

Quality

Excellent

Value for Money

Good

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Good

How do you feel about the size?

True to size

2025 januar 16E14Shopper

As Expected

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Nice and thick, just what you need on these freezing cold days

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Excellent

How do you feel about the size?

True to size

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