M&S Collection

Heatgen™ Thermal Long Sleeve Top

Size out of stock
Please select the size

We only list UK sizes. If you're not sure what your UK size is, please click on ‘Size advisor’ or review our size guides.


This sleek round neck thermal top is a fabulous way to keep warm and stylish when winter arrives. With our clever Heatgen™ technology giving a comfy, lightweight and beautifully flattering fit with added stretch, this women’s thermal top will be your foundation for cold weather fashion. All of the cotton for our clothing is sustainably sourced and always will be.

  • Product ID: T32/9100


    • Scoop neck, Added stretch
    • Smokey blue: 68% acrylic, 27% cotton and 5% elastane,Dark raspberry: 68% acrylic, 27% cotton and 5% elastane,All other colours: 66% acrylic, 29% viscose and 5% elastane
    • Machine washable
  • You may return unused products within 35 days of purchase.

    How to return:

    1. FREE returns to stores. The select M&S click and collect stores can be found here

    2. Self-postage return to the UK. Return your parcel at your own cost through your preferred carrier. Print your returns label and note here.

    FREE Delivery to Store: 3-4 working days. This delivery option is not currently available.

    EXPRESS DELIVERY: 2-3 working days. FREE for orders over £75, otherwise £5.99.

    Standard Tracked Delivery: 3-4 working days. FREE over £50, otherwise £3.50.

    Learn more

Complete the set...
Heatgen™ Thermal Long Sleeve Top is rated 4.6 out of 5 by 2838.
Rated 5 out of 5 by from Base layer top I wear these tops all year round, a long sleeve lightweight top for summer evenings and a thermal base layer the rest of the year. I do not like the cold at all but am able to wear the heatgen tops without them being too bulky under everyday work clothes. The neckline is just right for me, in-between a crew and a scoop. They wash well and keep their shape. They fold up small for storage and travel, and don't need to be ironed. They come in a varied range of colours (I have 5 now) The material is nice and smooth and the little bit of stretch makes them very comfy. Have recently bought 2 for my mum and she loves them too.
Date published: 2015-02-11
Rated 4 out of 5 by from Eenie Meenie Miney Mo! I have just started with Heatgen and have two of these tops so far this winter. I am around 5'8" and find the tops fairly long and close fitting but comfortable and good for wearing under my scoop neck jumpers (typical M&S style!). However, the arms are very long and, even though I turn them up, they wriggle down and poke out at the bottom of my top layer. For warmth and cosiness think I prefer the pointelle tops but the necks on these are high and cannot be worn with everything. Horses for courses, as they say . . . . ! PS - I would also like to find a thermal with a three quarter sleeve that can be worn under a shirt.
Date published: 2014-11-08
Rated 4 out of 5 by from Too short. Ordered a size 18. I expected a long length which is what I wanted to prevent cold air on the back. When the Item arrived it was obvious that it was too short. The body fit is good although would prefer a little more looseness. The length just about goes below the waist line on trousers. Is there a longer length available ? The idea of thermal wear is to keep you warm. So M and S should have allowances for the fact that people sometimes have to bend over, and when the vest rides right up the back then this area is going to get cold ! The quality and feel of the vest is lovely though. Unfortunately I had to return it.
Date published: 2016-12-26
Rated 5 out of 5 by from cosy tops I haven't actually worn any of the thermal tops/T-shirts yet -- too warm just yet. However, I bought two last year and they were wonderful. They are all lovely - and different colours. They are light and are really excellent for wearing under a jacket when the days begin to get a bit cooler. It is also lovely to not have to wear piles of clothes in the winter -- I am always frozen!! so it is nice not to look like a yeti! They don't look like naff thermal wear either but just like a normal, long- sleeved T-shirt. Definitely worthwhile. Sits neatly about hip level so looks nice with a skirt or under trousers.
Date published: 2016-09-21
Rated 5 out of 5 by from Ultimate flexibility I have almost every colour, style and design of top in the heatgen range. Quite simply they are the most flexible tops that I have. In summer it is light enough to be worn as a smart top for an evening out, or a casual top for those chilly windy days. Thin enough to be worn under a light summer jacket or smart enough to be worn on it's own. In winter they are superb as a base layer under a fleece, an evening top under a cardigan, with the sparkle as an evening top. For travelling, summer or winter, easily washed, dry overnight, and with that hint of stretch making it highly crease resistant. Superb.
Date published: 2015-10-09
Rated 5 out of 5 by from Heatgen Long Sleeve Top I think these are one of the best undergarments M&S produce, and I own many. I have bought the red, which is almost "pillar box" red in shade, to wear under a long sleeve black cardigan as an extra layer. The best thing about these vests is that they do not ride up and down as you move with the result that you forget that you are wearing a vest. They also wash well. Two very small criticisms. The neckline this year seems a little lower, with the result that there is quite an expanse of flesh. It seems too that there are only matt colours. Previously there have been a range of tops with added sparkle. Otherwise very happy.
Date published: 2016-11-30
Rated 4 out of 5 by from Heatgen long sleeved top I must have this top in around 10 colours now and do wear them a lot as base layers. They are definitely true to size and not generous in terms of size but that's good as I wouldn't want them to be loose and bulk up the layers I wear over them. I am hoping however that the material and finishing has improved since last year as quite a few of last years' tops have faded, become fluffy and the hems have become unstitched. I only buy these when discounted as I think £15.00 is a bit steep when they haven't lasted and also there are other similar options available in many stores that are sub £15.00. Incredibly useful and soft to wear, just hope this season they are a bit harder wearing.
Date published: 2015-10-27
Rated 5 out of 5 by from Great for layering I bought a couple of these Heatgen tops last winter and when they appeared in my inbox in a sale, I wasted no time ordering more. The colour is great (I got one in orange and another in teal) and the sleeves are actually long enough for me. I work in a church part-time and it is every bit as cold as you'd expect; I also have permanent side-effects from chemotherapy meaning I feel the cold but also get hot flushes so layering is essential for me. I can wear one of these tops with a strappy vest underneath and another long-sleeve top over and am comfortable without feeling like I'm wearing my entire wardrobe at once. I'd recommend these without a moment's hesitation.
Date published: 2015-02-04
  • y_2020, m_7, d_2, h_15
  • bvseo_bulk, prod_bvrr, vn_bulk_3.0.9
  • cp_1, bvpage1
  • co_hasreviews, tv_0, tr_2838
  • loc_en_GB, sid_P22405753, prod, sort_[SortEntry(order=RELEVANCE, direction=DESCENDING)]
  • clientName_marksandspencer-flagship
  • bvseo_sdk, dw_cartridge, 16.1.1, p_sdk_3.2.0
  • CLOUD, getContent, 169ms
  • reviews, product
Select size