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Heatgen™ Maximum Thermal Fleece Top

Product code: T329224

About this style

Embrace warmth with this Heatgen™ Maximum Thermal Fleece top. The luxuriously soft fleece fabric features our innovative Heatgen™ technology for superior insulation during the coldest weather. Long sleeves and added stretch ensure a comfortable, flexible fit that moves with your body while maintaining heat retention. The sleek design makes it perfect for layering or wearing alone for maximum thermal protection. M&S Collection: Easy-to-wear wardrobe staples that combine classic and contemporary styles.

M&S

Heatgen™ Maximum Thermal Fleece Top

€29

Colour

Size

Also available in: Tops
Free standard delivery over €75, otherwise €4.50

Reviews (1220)

4.8

79% Recommended this product

Mentions
18 September 2026Resolution16

Really do "love that"

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

I have a large collection of these, added to every year.Glad to see the range of colours available is slowly increasing. They are comfortable to wear hold their shape wash after wash &I like having them in different heat settings. As a pensioner in a large unheated house with an extreme dislike of being cold & an even greater dislike of the way my electricity bill is going up these are indeed a few of my favourite things.

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

14 September 2026MargaretAlison

Great Quality

Originally posted on marksandspencer.com (UK)

As it says on the tin. Just as described on line Excellent quality, soft and warm.

Helpful?

12 September 2026Manxy1

Chocolate brown thermal top

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

I stock pile these in advance of the colder weather coming. I’ve got loads of these tops in different colours. This time I wanted chocolate brown. I actually wear these tops as outerwear & not hidden underwear. I’m a size 12 on my top half, but so these aren't too clingy I buy a size 14.

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

11 September 2026LavenderandLace

Great in cold weather

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Bought this top in chocolate brown, having purchased other colours in past years, Warm, comfortable and washes well.

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

11 September 2026Hay1ey82

Thermal Fleece Top

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

I have bought a few of these tops over the years. This one is just as cosy and soft. Lovely thick material, washes well and a gorgeous autumnal/ winter colour. I always size up in these, I'm a size 16 / 18 and got the top in a size 20. It's still snug, but I wear them under other toos so I don't mind it looking a little tight.

Reviewer Ratings

How do you feel about the size?

Small

Helpful?

Reviewer Ratings

How do you feel about the size?

Small

30 August 20268yellowhoneybees

Soft comfortable top

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

I was very keen to buy these thermal tops. I like the fleece look and want to wear it as a top not an under garment. I prefer the crew neck to the high neck. I wish they did more colours, been trying to get the navy but the sizes are never in stock. Unfortunately they come up very small, had to return and buy a bigger size then still rather tight. I should have read the reviews before purchasing. Never the less soft and warm for winter just buy one or two sizes bigger.

Reviewer Ratings

How do you feel about the size?

Very small

Helpful?

Reviewer Ratings

How do you feel about the size?

Very small

28 August 2026Persil lady

Perfect.

Originally posted on marksandspencer.com (UK)

These heat gems are lovely,very warm and snug,selection of colours so you can mix and match,wash beautiful too,great for winter under your jumpers.

Helpful?

22 August 2026BUN 49

Terrible fit

Originally posted on marksandspencer.com (UK)

No, I don't recommend this

The top is very small to size. I bought for my mother who is at most a size 10. Very tight and uncomfortable

Helpful?

22 August 2026Sandexs

Cant be without in the winter

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

I work in a shop that is so cold inthe winter. These arent bulky and make all the difference. They wash amd dry perfectly and dont shrink. True to size. If yiu habe bigger arms, i would suggest going up a size. Its not shapewear, but they fit snug and hold you in If you dont want that feeling, size up

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

19 August 2026Signoraslim

Great for winter warmth.

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

I love these cosy thermal tops. The cream colour that I bought this time is very versatile.

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

02 June 2026Westlondonlass

Heatgen thermal fleece top

Originally posted on marksandspencer.com (UK)

For a size 16 it was more like a size 8. Quite long in the body also.

Helpful?

26 May 20261ladyinlincolnshire

Stylish and warm

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Great quality lovely and warm quite fitted I sized up

Reviewer Ratings

How do you feel about the size?

A bit small

Helpful?

Reviewer Ratings

How do you feel about the size?

A bit small

16 May 2026Paul Roland

Love it!

Originally posted on marksandspencer.com (UK)

I love Marks thermals, I wear them all the time in the winter and they are great for those in-between days too. The material is so soft, and a great price. I do have to go one size up though.

Reviewer Ratings

How do you feel about the size?

Small

Helpful?

Reviewer Ratings

How do you feel about the size?

Small

04 May 2026Silly name restriction

Good product but sizing runs small.

Yes, I recommend this

Good quality however sizing not quite right. I am a standard normal 12 pretty much everywhere. This was far too small and it had to be sent back.

Reviewer Ratings

Quality

Excellent

Value for Money

Good

Helpful?

Reviewer Ratings

Quality

Excellent

Value for Money

Good

01 May 2026LJS46

Super warm

Originally posted on marksandspencer.com (UK)

Purchased this top in both brown and cream. Its unbelievably warm and very soft. A nice long body which I appreciate. I sized up two sizes and it was still quite fitted.

Reviewer Ratings

How do you feel about the size?

Small

Helpful?

Reviewer Ratings

How do you feel about the size?

Small

16 April 2026RWK

Like a lovely hug

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

So soft and warm, yet light and not too thick. Has saved me on many occasions when I would have otherwise been cold. Great for wearing under another jumper or sweatshirt on really cold days. Highly recommended - I'll be buying more of these.

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

11 April 2026K10000

Look smart and warm

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Super warm. I bought them for skiing but actually wore them on rotation in the UK weather. The material is not thin.

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

05 April 2026NT0001

Wardrobe staple

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Love these tops. Really warm and soft. I practically live in these during winter!

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

03 April 2026sugarplumb

Affordable quality thermal top

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

m&s thermal tops are a must have in every wardrobe the warmth and quality cannot be faulted they are a much welcomed gift as we all enjoy comfort and these are so comfortable I do wish they had more variety in colours especially we women have been waiting a long time for a navy thermal top. I highly recommend this garment .

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

03 April 2026Walfie

Beautiful

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

I love this top, it’s super soft, comfortable and warm…I went on to buy two more. Well made. Washes well and good sizing

Reviewer Ratings

How do you feel about the size?

True to size

Helpful?

Reviewer Ratings

How do you feel about the size?

True to size

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