Marks & Spencer's £20 thermal fleece leggings shoppers love and 'will keep you warm until spring'

The Heatgen Maximum Thermal Fleece Leggings are available in four colours - and are selling fast

As the cold weather bites, shoppers are rushing to Marks & Spencer to buy these 'warm' and cosy' thermal fleece leggings for just £20. The Heatgen Maximum Thermal Fleece Leggings 'will keep you warm until spring' according to fans who have already snapped them up.

The Heatgen Maximum Thermal Fleece Leggings are available in four colours - black, grey marl, dark chocolate and navy. They are available in sizes 6 to 22.

But be quick - as they are listed as 'selling fast' on Marks & Spencer's website.

Read more: New £45 Marks & Spencer cardigan is so 'warm and snug' and will be great for 'chilly days'

Read next: 'Chunky' Marks & Spencer £50 black boots are 'absolutely outstanding' as fans say '100% recommend'

A product description reads: "These thermal leggings are lined with fleece for a super-cosy feel. They feature our Heatgen™ maximum warmth technology which effectively traps body heat to keep you warm and cosy. Plenty of added stretch means they move with you for a comfortable fit."

The Heatgen Maximum Thermal Fleece Leggings have a 4.4 star rating on Marks & Spencer's website. One shopper said: "I love these pants. They fit amazingly and keep my legs extremely warm. More colours please."

San wrote: "Having previously worn the medium thermal, this is going keep me warm till next spring I will be buying more." A third shopper commented: "Live in these in the colder months. Have different tog ratings and colours."

Alix posted: "Warm and cosy, so pleased to have discovered them . I bought my usual size 14 and found them true to size, I’m 5.4 and they are quite long on me, so will just turn them over . I don’t think they come in different lengths? Would recommend them."

And Sue added: "Absolutely gorgeous cosy thermal leggings. Just right for autumn and winter."

While one unhappy shopper said: "I have had these type of leggings several times over the last few years and have loved them. The only ones I could find that keep me warm in colder weather. Sadly, this time, although the material was great…the length of the leg had increased by at least 3-4inches!! Have to go back. No idea how I’m going to keep warm now."

You can buy the Heatgen Maximum Thermal Fleece Leggings for £20 on Marks & Spencer's website now. M&S also have these Heatgen Medium Thermal Brushed Leggings for £16.

Elsewhere, Next has these Black Fleece Lined Thermal Tights for £12.50. John Lewis' Micro Warmth Thermal Leggings cost £20. While Amazon sells the Mountain Warehouse IsoTherm Womens Brushed Leggings from £7.99.