Looking for the best ethical and sustainable thermals to keep you cosy? Here are my top picks – from vegan-friendly bamboo to cosy ethically sourced merino wool and more.
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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 have always been the original energy savers. In fact, I feel like I’ve learned almost all that 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.
But life has now gone full circle, and in response to rising energy bills, I’ve found myself thinking that my parents have been on to something all these years. 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
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+
Finisterre Bamboo & Natural Fibre Thermals
Budget: £ – ££
Caters for sizes: Men’s XS – XXL / Women’s 6 – 18
Whether you are looking for vegan-friendly bamboo baselayers, or you prefer natural fibres such as merino wool, then Finisterre* has you covered. Catering for both men and women, Finisterre 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.
In terms of ethical credentials, Finisterre is the real deal. Since their inception in 2003, sustainability has been at the heart of everything they do. From their commitment to using plastic-free packaging to their commitment to using the most sustainable fabrics possible, Finistere has carefully considered all aspects of its business.
For example, they have always used non-mulesed wool for all of their Merino base layers and knitwear. Their Merino wool comes from traceable suppliers, for guaranteed non-mulesed sheep.
Finisterre will also help you to repair your Finisterre clothes, or they will repair them for you if you can’t. And when your clothes wear out, they offer a handy takeback scheme. Here they will either upcycle your old clothes into new products or fully recycle them.
And in 2018, Finisterre became B Corp Certified. This means that Finisterre has been independently certified as a business that is committed to prioritising the environment and society in every aspect of its activities.
Organic Basics Sustainable Tencel Thermals
Budget: £ – ££
Caters for sizes: XS – XXL
Organic Basics offer a range of men’s ethical long johns*, women’s leggings and baselayer tops for both men and women, all made from Tencel. This is an eco-friendly and vegan-friendly fabric, made from wood pulp, that is very durable and breathable, yet smoother than cotton and softer than silk.
Having tried it out, I would say Organic Basic’s collection is less on the technical side and more of an everyday sustainable thermal. Layer up in them for keeping cosy at home, or for keeping warm whilst out and about in the winter months, without feeling sweaty.
Again, sustainability has always been Organic Basic’s core mission. As such, every aspect of their operations is carefully considered. From plastic-free packaging to quality eco-friendly fabrics that are designed to last. Organic Basics also avoid making seasonal collections to minimise wastage – instead, focusing on timeless styles. Organic Basics also only partners with factories that care about their impact.
Use discount code WENDYOBC to take 10% off your order.
Joha Natural Fibre Thermals
Caters for sizes XS – XXL
For cosy ethical thermal baselayers, then try Joha*, a Scandinavian brand 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 their 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 their 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.
BAM: Bamboo Thermals
Budget: £ – ££
Caters for sizes: men’s S – XXL / women’s 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.
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.
From long sleeve to short sleeve tops, and zip neck tops to help keep your neck cosy, to long johns for men, BAM has a great selection.
What’s more, BAM only works with responsible producers. For example, they only work with bamboo fibre producers who use safe and responsible chemistry and waste treatment practices, and who are committed to investing in the technology needed to further improve their practices, processes, and chemistry where necessary.
They also ensure that their suppliers are paying their staff above the national minimum wage and are offering good working conditions throughout the entire supply chain.
I wrote more about BAM and its ethical commitments – if you are interested in reading more.
As always, as I come across more thermals, I’ll be sure to add them here, so do check back again.
Main image used c/o Finisterre