Guide To UK Ethical & Sustainable Thermals Brands
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Looking for the best ethical and sustainable thermals to keep you cosy? Here are my top picks from UK brands for men, women, and children – including vegan-friendly bamboo, cosy ethically sourced merino wool, and more.
I used to think thermals were just for mountaineers and skiers. And then, quite some years ago, my parents retired. Suddenly, their wardrobes expanded with a full array of thermals for almost every occasion.
I thought they had taken up mountain climbing or some other kind of alpine pursuit. And then I realised, no. There were no alpine adventures. They were just looking for ways to keep the heating off for as long as possible, now that they were at home much more often.
My parents were always the original energy savers. In fact, I feel like I have learned almost everything I know about saving energy from them. But I’ll be honest, I did giggle at them when they were decked out in all their thermals.
However, life has now gone full circle, and in response to rising energy bills, I’ve found myself thinking that my parents were perhaps onto something.
As such, I’ve found myself searching for sustainable thermals as a way to keep warm when working from home without resorting to cranking up the heating.
So whether you are concerned about heating costs and are looking for a way to stay cosy at home without turning on your heating so much. Or, whether you are looking to get out on some alpine adventures without freezing your bits off, then here are the best ethical thermals I’ve found.
Ethical and Sustainable Thermals Guide
No matter if you are vegan or you prefer natural fibres, I’ve sourced the most sustainable and ethical thermals. From performance wear to casual wear, there’s something for every circumstance.
To help you out, I’ve included a rough price range for each brand. The key to this guide is:
£ = Under £50 | ££ = £50 – 100 | £££ = £100+
BAM
- Budget: £ – ££
- Caters for: Men (sizes S – XXL) and Women (UK sizes 8 – 16)
For vegan-friendly base layers, hot-foot it to BAM. With bamboo baselayers for both men and women, these soft and stretchy insulating base layers help to keep you warm on even the coldest days. Find long-sleeve, short-sleeve, and zip-neck tops, as well as long johns.
Designed for both performance and comfort, the flatlock stitching means these sustainable thermals are chafe-free.
Made from bamboo jersey blended with organic cotton, this sweat-wicking blend is designed to be just thick enough to keep you warm, yet highly breathable so you don’t overheat. The blend is also incredibly absorbent, so it helps you to stay dry, helping you with your temperature control.
In terms of ethics, BAM only works with responsible producers. For example, BAM only works with bamboo fibre producers who use safe and responsible chemistry and waste treatment practices. These producers are committed to investing in the technology needed to further improve their practices, processes, and chemistry where necessary.
BAM also ensures that its suppliers are paying their staff above the national minimum wage and are offering good working conditions throughout the entire supply chain.
Get 10% off your first order when you sign up for the BAM mailing list.
Findra
- Budget: ££
- Caters for: Women (UK sizes 8 – 18)
Scottish sustainable brand Findra specialises in activewear made from natural and recycled sustainable fabrics. Its extensive range of ethical thermals and base layers – from tops to underpants – are all made from mulesing-free merino wool. These are made using clever zero-waste knitting techniques.
As well as a commitment to sustainable fabrics, Findra manufactures more than half of its collection in the UK – in Scotland and England. For items made outside the UK, Findra only works with factories that are certified to the highest standards both in environmental performance and labour conditions.
To help your Findra garments last as long as possible, there’s a handy repair service for your garments, should they get damaged.
Get 20% off your first order when you sign up for the Findra mailing list.
Polarn O. Pyret
- Budget: £
- Caters for: Children (ages 0 – 12 years)
When it comes to kids’ ethical thermals, Polarn O. Pyret is a solid, sustainable choice, and at pretty reasonable prices too.
Offering thermals made from responsibly sourced wool and recycled materials, for babies up to kids aged 12 years, it’s a great place to pick up thermals that will last and last. In fact, Polarn O. Pyret says that every garment is made to last at least 3 children, if not many more.
Polarn O. Pyret also runs a buy-back scheme. Here, when your child grows out of their Polarn O. Pyret clothes, it will help you find a new owner for them. In return, you’ll receive a voucher to use on new items online.
Finisterre
- Budget: £ – ££
- Caters for: Men (sizes XS – XXL) and Women (UK sizes 6 – 18)
If you are looking for natural fibre baselayers, then sustainable outdoor brand Finisterre has you covered.
Catering for both men and women, this certified B Corp (meaning it prioritises people and planet) has a huge range of sustainable thermals. From long johns to boxers, long-sleeved and short-sleeved layers to cosy roll necks, this is Finisterre’s speciality. These are all made from non-mulesed merino wool, which comes from traceable suppliers.
Since its inception in 2003, sustainability has been at the heart of everything Finisterre does. From its commitment to using plastic-free packaging through to using the most sustainable fabrics possible, Finistere has carefully considered all aspects of its business.
Finisterre also runs an impressive repair service, helping customers extend the life of their clothes, and a takeback scheme that ensures worn-out garments are either upcycled or recycled.
Get 10% off your first order when you sign up for the Finisterre mailing list.
Joha
- Budget: £
- Caters for: Men (sizes S – XXL), Women (sizes XS – XXL), and Children (ages 0 – 15)
For cosy ethical thermal baselayers, then try Joha, a Scandinavian brand (available in the UK at Alpinetrek) that’s been going for over 50 years.
When it comes to thermals, this brand knows its stuff – it only makes thermals and makes them well. All of its products – from long johns to vests, boxers, and long-sleeve tops – are made from mulesing-free merino wool and/or organic cotton. There are no synthetic fibres here.
What’s more, all of its products have Oeko-Tex Standard 100 certification. This means that every component – right down to the thread – has been tested for harmful substances. For extra peace of mind, Joha also holds Scandinavian independent certification for the responsible sourcing of wool.
Get £5 off your first order when you sign up for the Alpinetrek mailing list.
More Resources To Keep You Ethically Cosy
Looking for more ways to keep cosy? I have you covered. Try my big guides to:
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