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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

£17

Colour

Customers say:

Fits true to size()
Size

Free standard delivery over £60

Reviews (237)

4.6

69% Recommended this product

Mentions
12 March 2026ALasa
Verified Purchase

Warm and stylish!!

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 did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

05 March 2026Jane Edinburgh
Verified Purchase

Lovely cosy purchase

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 did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

27 February 2026loonietunes
Verified Purchase

Great quality & fit

Yes, I recommend this

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

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

26 February 2026Ylaffe1
Verified Purchase

Bobbled on first wear

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 did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

24 February 2026Renau
Verified Purchase

Keeping warm in style.

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 did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

24 February 2026YC2stanton
Verified Purchase

Gentle warmth

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
Verified Purchase

Excellent warm top

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 did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

19 February 20265PK
Verified Purchase

Great material & does the job!

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 did it fit?

Large

Helpful?

Reviewer Ratings

How did it fit?

Large

19 February 2026SEL13
Verified Purchase

Perfect top

Yes, I recommend this

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

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

16 February 2026Izzibella
Verified Purchase

Good but bobbles after only 2 wears

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 did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

16 February 2026LeoSuki
Verified Purchase

Love it

Yes, I recommend this

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

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

15 February 2026Daisyanne
Verified Purchase

Stylish, warm & cosy

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 did it fit?

A bit small

Helpful?

Reviewer Ratings

How did it fit?

A bit small

13 February 2026Quirky 72
Verified Purchase

Simply the best!

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 did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

13 February 2026
Verified Purchase

Bobbled after one use.

No, I don't recommend this

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

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

13 February 2026Barb 56
Verified Purchase

So comfy

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 did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

12 February 2026123Emmer123
Verified Purchase

Stylish looks at a good price

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 did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

09 February 2026Tuppence4
Verified Purchase

Warm layer

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
Verified Purchase

Excellent layer

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 did it fit?

A bit small

Helpful?

Reviewer Ratings

How did it fit?

A bit small

04 February 2026Kazling
Verified Purchase

Lovely soft top

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 did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

04 February 2026Alison175
Verified Purchase

Excellent

Yes, I recommend this

Great fit, nice top, great for keeping warm in winter

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

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