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Heatgen™ Maximum Thermal Fleece Leggings

Product code: T327303

About this style

These thermal leggings offer maximum warmth with our innovative Heatgen™ technology that effectively traps body heat when temperatures drop. The soft fleece lining provides a luxuriously cosy feel against the skin, while the stretchy fabric ensures a comfortable fit that moves with you throughout the day. The clean, streamlined design makes these leggings perfect for layering or wearing alone during colder months. M&S Collection: Easy-to-wear wardrobe staples that combine classic and contemporary styles.

M&S

Heatgen™ Maximum Thermal Fleece Leggings

€29

Colour

Waist

Matching items: Thermal Fleece Top and Thermal Top
Free standard delivery over €75, otherwise €4.50

Reviews (1210)

4.7

78% Recommended this product

Mentions
11 September 2026Kazzz34

Brown leggings size 10

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Purchased for Autumn and have only tried them on to see if they fit... a little baggy around thighs but I have lost a lot of weight due to illness. Will be wearing with a tunic in the colder months.

Reviewer Ratings

How do you feel about the size?

A bit large

Helpful?

Reviewer Ratings

How do you feel about the size?

A bit large

11 September 2026Lizzie127

Lovely and warm

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

For myself, purchased last winter, so warm and comfortable , I purchased early to make sure I got my size.

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 Leggings

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

So thick and warm. Love these and I get a new pair each year. I am size 16 / 18 and got a size 20 as they are normally on the smaller side in terms of the sizing.

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

10 September 2026BVid

Good leggings.

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Good quality. Kept me warm on a cold day! Very soft material. Shame they are so expensive

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 September 2026ClaireH24

Excellent

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Warm cosy and absolutely useful for home working at a desk all day

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

22 August 2026BUN 49

Terrible fit

Originally posted on marksandspencer.com (UK)

No, I don't recommend this

Very small and uncomfortable , would not recommend

Helpful?

22 August 2026Sandexs

So good!

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

I get these for winter at work. They arent too thick to wear under your regular clothes. They wash and dry well. And they last for ages. I onky had to buy more because i needed a smaller size. They are form fitting almost like a light shapewear. So if you want them more loose fitting, go up a size

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

28 June 2026K happy

The winter ‘Must Have’

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

I love these leggings - you can use them as tights or leggings and they are so warm and quite robust. They can also go under trousers etc. I hate to be cold and these leggings mean I don’t have to be.

Reviewer Ratings

How do you feel about the size?

A bit large

Helpful?

Reviewer Ratings

How do you feel about the size?

A bit large

19 June 2026Madelaine56

So good!

Originally posted on marksandspencer.com (UK)

I've bought several pairs of these very soft and warm thermals. I love them. So comfy and so warm. They double as usual dergarments in the daytime and pyjamas at night. Would highly recommend!

Helpful?

24 May 2026JR04

Good quality but far too long

Originally posted on marksandspencer.com (UK)

I've had Heatgen leggings in the past that have washed well and was keen to replace them. I had to go a size less ( even though I'm the same weight) and the length far too long so will have to get them turned up.The medium thermal were thinner and the maximum thermal thicker so not able to find an exact replacement. They are good quality but a shame not to find a similar type.

Helpful?

19 April 2026Emma3878

Warm, soft and comfortable

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Gorgeous legging, so soft and warm, runs big to size so recommend a size down

Reviewer Ratings

How do you feel about the size?

Large

Helpful?

Reviewer Ratings

How do you feel about the size?

Large

14 April 2026Auntie81

Very warm.

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Really warm and comfy.Great price. Love them. Well worth the money.

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 April 2026Charlotte JSB

Soft and comfy

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Lovely soft leggins. Lightweight but warm and cosy.

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 2026Charlotte 14

Love them

Originally posted on marksandspencer.com (UK)

I bought these in the sale . Brilliant lovely and warm wish l had bought them years ago . Bought more can you do extra short .recommend them

Helpful?

04 April 2026Caroles2

Heathen thermal leggins

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

These are really warm and comfortable. Love wearing 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

04 April 2026LC 2

Just a little long.

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Good quality for the price. Will hopefully be warm as I have bought them for a winter holiday. I’m 5ft 4ins & whilst they are a little long on me I have kept them,choice of length would be good. I think I will buy another pair in brown.

Reviewer Ratings

How do you feel about the size?

A bit large

Helpful?

Reviewer Ratings

How do you feel about the size?

A bit large

02 April 2026Topaz62

Not great

Originally posted on marksandspencer.com (UK)

No, I don't recommend this

These are lovely & soft but unfortunately just after a couple of washes they 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

31 March 2026Jenyo

Super warmth

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Best I have found to keep cold and damp at bay, aching joints no longer ache

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

30 March 2026pezza999

Toasty Thermals

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

Great leggings to match thermal top. Very warm and cosy to wear

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

29 March 2026Justu

Excellent

Originally posted on marksandspencer.com (UK)

Yes, I recommend this

These leggins are great, I wear mine just around the house & yes they are a bit long as I’m only 5ft3 but they still look ok, tgey wash & it oh great but I don’t tumble dry them.

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

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