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M&S

Heatgen™ Maximum Thermal Fleece Top

£22

Colour

Customers say:

Fits true to size()
Std Dress Size

Matching items: Thermal Leggings
Also available in: Tops
Free standard delivery over £60

Product code: T329225

About this style

Stay cosy during the coldest weather in our Heatgen™ Maximum Thermal fleece top. The high mock neck and long sleeves provide extra warmth, while the soft fleece with added stretch ensures a comfortable fit. Our warmest thermal technology yet keeps you snug without bulk, letting you embrace winter with confidence. M&S Collection: Easy-to-wear wardrobe staples that combine classic and contemporary styles.

Details & care

Item details

Model Height: 5ft9"/176cm

Model is wearing size: 12

Style

Added Stretch

Features

Heatgen™ technology

lightweight and supersoft, designed to keep you warm when the weather gets chilly

Composition

55% acrylic, 37% viscose and 8% elastane (exclusive of trimmings)

Care

Wash at 40°C

Do not bleach

Do not tumble dry

Do not iron

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 (795)

4.5

70% Recommended this product

Mentions
08 February 2026Starsky53
Verified Purchase

Great

Yes, I recommend this

After having bought heatgen items for many years now I needed a new warm top and after reading other reviews decided to get my usual size and not larger as know from walking days these are more a base layer so need to fit snugly and not loose like a normal top. It has proved its worth and just wish my local branch stocked more variety of the designs and colours you see on the website.

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

07 February 2026CatherineKeys
Verified Purchase

Great quality

Lovely thermal top. Nice funnel neck ….. I wear mine as a top rather than base layer.

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

07 February 2026j0567
Verified Purchase

Maximum warmth fleece

Yes, I recommend this

Really warm and good colour, I would have preferred a proper turtle neck or roll neck but it didn’t put me off buying another one. I bought one size up and it’s still snug and fits well.

Reviewer Ratings

How did it fit?

A bit small

Helpful?

Reviewer Ratings

How did it fit?

A bit small

07 February 2026ariadne49
Verified Purchase

Gorgeous and warm.

Yes, I recommend this

I have a number of these fleece tops. Lovely and warm. I go up a size to get a longer length to ensure body coverage to fit inside the leggings. .

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

06 February 2026FeeFeeEllaFlower
Verified Purchase

Lovely & warm

Yes, I recommend this

Lovely, cosy top that keeps me warm while working outdoors.

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

06 February 2026Psudonym
Verified Purchase

Thermal Turtle

Yes, I recommend this

I like this jumper because the neckline sits above a crew neck which is good as I like to layer up in Winter. I have bought Heatgen products from Marks before but this is the thickest and cosiest one yet, and is soft on the inside and outside. I chose navy which is very versatile to team up with other items.

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

06 February 2026Liz of Followtheboat
Verified Purchase

Outstanding warmth and cosiness

Yes, I recommend this

Bought two of these to wear under jumpers and jackets. They are snug, pretty much skintight; also thick enough to look good on their own, without a bra outline showing.

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

05 February 2026LezahEv
Verified Purchase

‘Turtle’ thermal

This was very warm but the ‘turtle’ style collar wasnt to my liking si I returned the item.

Helpful?

05 February 2026Blueberry 45
Verified Purchase

Warm thermal top

This keeps me warm, it soft and cozy. I'm not keen on the funnel neck but apart from that it's good and I would recommend.

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

04 February 2026EllabellaBallerina
Verified Purchase

Warm

No, I don't recommend this

Warm but comes up small, should have returned and ordered next size up. Also not sure I like the neckline (doesn't feel right somehow)

Reviewer Ratings

How did it fit?

Small

Helpful?

Reviewer Ratings

How did it fit?

Small

03 February 2026Matcal
Verified Purchase

Third one!

Yes, I recommend this

This is the third thermal top of this design that I have bought. The others are in different colours. The top certainly keeps you cosy and washes easily. It doesn’t tumble dry however and that could be a downside.

Reviewer Ratings

How did it fit?

A bit small

Helpful?

Reviewer Ratings

How did it fit?

A bit small

03 February 2026Bluebell babe
Verified Purchase

Cosy and warm

Yes, I recommend this

Super cosy and great fit too, bought one in black and one in cream colour

Reviewer Ratings

How did it fit?

A bit small

Helpful?

Reviewer Ratings

How did it fit?

A bit small

02 February 2026Kymarika
Verified Purchase

Keeps lower chest warm.

I have given four stars as I have not tried it on yet. Looks perfect, great colour and texture.

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

02 February 2026LesleyHM
Verified Purchase

Stylish and warm

Yes, I recommend this

Present for my mum to wear under her clothes during the winter to keep her warm - absolutely perfect

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

01 February 2026Disappointed of Welshpool
Verified Purchase

So comfy and cosy

Yes, I recommend this

Very pleased with this top. Lovely material, nice generous fit.

Reviewer Ratings

How did it fit?

A bit large

Helpful?

Reviewer Ratings

How did it fit?

A bit large

31 January 2026AKW61
Verified Purchase

highly recommended

Yes, I recommend this

Really cosy thermal top that looks good too. I have this top in black and olive green and they have been really useful during the cold weather

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

31 January 2026HJ Twinkle
Verified Purchase

Very warm!

I like this because it’s long enough to tuck in, keeps me very warm.

Helpful?

31 January 2026Spotty cat
Verified Purchase

Great pay

Not too busy and warm. Similar and elegantly. Happy with it. Can coordinate with any styles.

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

30 January 2026Ell59
Verified Purchase

Lovely Warm Nice Quality Tops

Yes, I recommend this

I bought some similar M&S thermal tops last year and wore them often in the colder months. They’ve always washed well and kept their colour (red and blue); unfortunately the bright red colour is not available this year, but there were 2 other colours which I liked and purchased as an alternative.

Reviewer Ratings

How did it fit?

True to size

Helpful?

Reviewer Ratings

How did it fit?

True to size

30 January 2026Allstyles
Verified Purchase

A necessary piece of clothing!

Beautifully warm. Neat neckline and good length that comes over the hips! Pleased I bought two!

Helpful?

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