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Heatgen™ Medium Thermal Mock Neck Top

Product code: T329223

About this style

This long-sleeved thermal shirt features our innovative Heatgen™ technology, offering medium-level warmth without adding bulk. The mock neck design provides extra coverage and comfort, while the stretchy fabric ensures a close yet flexible fit that works perfectly as a base layer for layering. Exceptionally soft against the skin, this item from the M&S Collection moves with you throughout the day. M&S Collection: Easy-to-wear wardrobe staples that combine classic and contemporary styles.

M&S

Heatgen™ Medium Thermal Mock Neck Top

€22

Colour

Size

Free standard delivery over €75

Reviews (237)

4.6

69% Recommended this product

12 March 2026ALasa

Warm and stylish!!

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

This top is not just warm but also stylish. It has a soft touch to the body and you can wear it as a top, not just an undergarment.

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 March 2026Jane Edinburgh

Lovely cosy purchase

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Glad I bought this along with a few other Heatgen Thermals when the offer was on but would have bought it full price as I’ve bought Heatgen previously and never been disappointed. Lovely cosy top.

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

27 February 2026loonietunes

Great quality & fit

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Top is of great quality & fits so well. Neck line is just enough

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

26 February 2026Ylaffe1

Bobbled on first wear

Originally posted on marksandspencer.com (UK)

No, I don't recommend this

When I first received this top I absolutely loved it and recommended it to friends, and it felt such lovely quality. Was warm without being sweaty. Gorgeous colourway & lovely neck line. However after 1 wear, I took the top off and it had all bobbled under the arms and around the back where I’d been sat against a chair. I wore it one more time and it became so bobbled I had to return it as faulty. Gutted because I can’t find this colour elsewhere. But the quality of Uniqlo thermals are much better as they don’t bobble.

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

24 February 2026Renau

Keeping warm in style.

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

This top works very well, first on it feels cool, pull a light shirt/jumper on and away it goes doing its thing, keeping you warm. Great!

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

24 February 2026YC2stanton

Gentle warmth

Originally posted on marksandspencer.com (UK)

Nicely fits with soft feeling on skin. Looks great on its own or worn under blouse.i chose black as it goes with everything. Great buy.

Helpful?

19 February 2026clothesnut

Excellent warm top

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Great warm top with looser neck so you don’t look strangled. I love the versatile colour. Worn under sleeveless jumpers gilets and on its own. Good buy

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 February 20265PK

Great material & does the job!

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Bought for a trip away and it certainly kept me warm and cosy. Lovely material, very soft and stretchy.

Reviewer Ratings

How do you feel about the size?

Large

Helpful?

Reviewer Ratings

How do you feel about the size?

Large

19 February 2026SEL13

Perfect top

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

This is my second thermal mock neck top. Looks great, comfortable and a valued wardrobe item.

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

16 February 2026Izzibella

Good but bobbles after only 2 wears

Originally posted on marksandspencer.com (UK)

Worn these kind of thermal but this beige one bobbled after 2nd wear, the black didn’t however disappointed as it’s a lovely colour

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

16 February 2026LeoSuki

Love it

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

I love this thermal mock neck top, very soft and warm.

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

15 February 2026Daisyanne

Stylish, warm & cosy

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Love this top. I’m normally a 14 but sized up to a 16 as I didn’t want it skin tight . It’s perfect. I will order another when it comes back into stock .

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

13 February 2026Quirky 72

Simply the best!

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

It is excellent, both the quality of the fabric and the design. I love the slightly raised neckline. It’s comfortable and looks classy!

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

13 February 2026

Bobbled after one use.

Originally posted on marksandspencer.com (UK)

No, I don't recommend this

Bobbled after one use - very disappointing and had to return.

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

13 February 2026Barb 56

So comfy

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

My first time buying heatgen top for myself. Have purchased for presents and was recommended by my niece. I’m loving it, so warm and very soft. Will be purchasing again.

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

12 February 2026123Emmer123

Stylish looks at a good price

Originally posted on marksandspencer.com (UK)

I am loving this thermal top. It’s soft and warm. The taupe colour is very flattering and the fit is good. I bought two and keep one for my Pilates class. It looks just like a more famous and expense sports brand, but costs far less.

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

09 February 2026Tuppence4

Warm layer

Originally posted on marksandspencer.com (UK)

Beautifully warm and soft layer. I would say go up at least 2 sizes unless you want a skin tight fit; hence 4 stars. More colours please.

Helpful?

06 February 2026Ruby789

Excellent layer

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Excellent thermal layer, I love the mock neck, keeps out the draughts. Size a bit smaller than expected so I have bought a size up from normal.

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

04 February 2026Kazling

Lovely soft top

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

I like the colour and softness of this top, which can be worn alone or under other garments.

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

04 February 2026Alison175

Excellent

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Great fit, nice top, great for keeping warm in 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

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