The Ultimate Guide To The Most And Least Sustainable Clothing Fabrics

31 October 2025

This blog explains the difference between sustainable and unsustainable fabrics to help you make more eco-friendly fashion choices!

There are many things to consider when trying to choose more sustainable clothing, but the fabric is one of the most important ones. Understanding clothing fabrics is one of the best ways you can build your wardrobe to be more sustainable and less polluting.

The fibres that make up our clothes determine not only how they look and feel, but also their impact on the planet. From the water used to grow crops to the microplastics released when washing synthetics, fabrics are at the core of fashion’s environmental and social impacts.

It can be confusing to know what is sustainable or not, since most clothing brands will try to market almost anything as a sustainable fabric. It’s important to understand the impact of a fabric from a full lifecycle perspective, not just the parts that a fashion brand wants you to focus on.

This guide breaks down the most and least sustainable clothing fabrics to help you build a more sustainable wardrobe.

Why is understanding fabric important for sustainable clothing?

All fabrics, natural or synthetic, take resources to create, and can pollute the environment during their lifecycle. There are broadly two areas to consider for the sustainability of a fabric: the impacts of making it, and the impacts of wearing it.

Choosing fabrics made responsibly helps cut waste, conserve resources, minimise carbon emissions, and support better farming or manufacturing practices.
But you also need to consider the impact of a clothing fabric’s wear and end-of life, like being durable, not release microplastics, and being recyclable or biodegradable when disposed.

There are 3 main categories of fabrics:

Natural fibres, either plant-based like cotton or animal-based like wool
Semi-synthetic, using a natural fibre as a raw ingredient but using synthetic processes to be turned into a fabric, like viscose or Lyocell
Synthetic, usually fossil-fuel based and using chemical processes to be turned into a fabric, like polyester or nylon.

Synthetic fibres are clearly the most polluting both in production and use, because they shed microplastics and don’t biodegrade. Natural fibres are usually called the most sustainable option, but a natural fibre does not guarantee sustainable fabric production. Semi-synthetic fabrics have this issue even more, so the production process needs to be designed to minimise the environmental impact to classify as a sustainable fabric.

I’ve tried my best to sort the most common fabrics into “sustainable” and “unsustainable”, but usually the story is more nuanced. No fabric is without impact, and fabrics can be produced differently depending on the supplier. But I’ve broken it down as clearly as possible, so you can make the best choices that align with your values.

Top 8 Most Sustainable Fabrics to Choose

Generally, materials made from natural and renewable sources are better then synthetic, plastic-based materials. However, natural fabrics are not automatically made in a sustainable way. There’s no perfect fabric, but these are some of the best options currently available.

1. Organic Cotton

A sustainable choice that is becoming increasingly more available is Organic Cotton. It is an alternative to the terrible environmental impact of conventional cotton, one of the most unsustainable fabrics out there.

Organic cotton is grown without synthetic pesticides or fertilisers and using regenerative farming techniques, helping to protect soil health, water quality, and farmers’ wellbeing. It uses less water than conventional cotton, requires less energy, and produces fewer carbon emissions (learn more here).¹ Look for GOTS or Organic Soil Association certifications to make sure it meets high environmental and social standards.

2. Linen

Linen is probably one of the most sustainable clothing fabrics on the market. Made from the flax plant, linen grows well in cooler climates with minimal water and fertiliser. Every part of the plant can be used, which means very little goes to waste.

Flax is resilient and can grow in poor soil, using far less water than cotton and requiring no chemical pesticides or fertiliser.² It’s strong, breathable, and biodegradable, and it only gets softer with wear. For an even better impact, try to find organic certified linen.

3. Hemp

Hemp is another amazing, but less available option. It grows quickly without synthetic pesticides or much water and can even improve the soil it grows in.³ It’s also super effective in sequestering carbon as an added environmental benefit. It produces a natural, slightly textured fabric that’s breathable and long-lasting. Again, where possible try to find organic certified hemp to be 100% sure no chemicals were used.

4. TENCEL™ Lyocell

Lyocell is a semi-synthetic cellulose fibre created by dissolving wood pulp, usually from eucalyptus, oak, and birch trees. The most well-known version of it is TENCEL™, a branded version. It is much more sustainable than other cellulose based fabrics (like viscose) because it is produced in a closed-loop system where most of the solvents and water are reused, and made from responsibly-sourced wood.⁴ The result is a soft, breathable, and biodegradable fabric.

As a side note, TENCEL™ also produces another cellulose fabric, called Modal. The modal process is more sustainable than regular viscose but it depends on manufacturer processes and it still uses chemicals. The TENCEL™ version is considered to be the most sustainable version, though less so than Lyocell, which is why it does not make it as a separate item on this list.⁵

5. Bamboo Lyocell

Bamboo is easy to grow, requiring little water and no pesticides, which is why it’s an increasingly popular ‘sustainable’ fibre. However, most bamboo fabrics on the market are made using the viscose process, processed with toxic chemicals to turn the plant pulp into a soft fibre, which is overall an unsustainable process.⁶

The sustainable version of bamboo fabric is produced using the lyocell process, with a closed loop system which recaptures chemicals and water, though it’s not as widely adopted yet. There’s also mechanically processed bamboo fabric, usually referred to as bamboo linen, though it’s rougher and less common. Overall, avoid fabrics just labelled as ‘bamboo’ since that just means it’s viscose, and try to find bamboo lyocell, sometimes under a branded name like Monocel.

6. Wool

Wool is a natural, renewable, and biodegradable fibre that offers warmth, durability, and breathability, so in that sense it’s a sustainable choice. However, its sustainability is compromised by how it is produced. Most sheep farming causes high methane emissions, significant land use affecting biodiversity and soil health, and has wide-spread animal cruelty practices.⁷

Wool is still much better than synthetic alternatives like acrylic or polyester, but to experience the benefits of wool sustainably, find wool certified by the Responsible Wool Standard, ZQ Merino Standard, or the Soil Association Organic Standards, though keep in mind the welfare guarantees for the animals differ. The most sustainable option is to go for second hand or recycled options.

7. Recycled Natural Fibres

Choosing recycled natural fibres, like cotton, wool, cashmere, leather, linen, hemp, and down, is a great way to reduce the environmental impact of clothing while keeping materials in use longer. Recycled cotton can be made from post- or pre-consumer waste, and is fully biodegradable, reducing reliance on resource-intensive virgin cotton.⁸ Recycled wool and cashmere similarly extend the life of animal fibres, while recycled leather gives existing hides a second life without further harm to animals.

Recycling does shorten the natural fibres, but they can be blended with virgin fibres for strength, though ideally natural ones, not synthetics.⁹ Overall, recycled natural fibres help close the loop, save resources, and support a more circular fashion system, making them a sustainable choice.

8. Recycled Synthetic Fabrics (From True Waste)

Recycled synthetics like recycled polyester, nylon, and others, appear in both my sustainable and unsustainable lists, because their impact is complicated to evaluate.

From a sustainable perspective, recycled synthetics reduce the need for virgin plastics by reusing waste like fishing nets, industrial scraps, or production offcuts, creating a more circular system and lowering energy use and emissions compared to virgin fabrics.¹⁰ When made from discarded fishing nets or textile-to-textile waste, they offer a genuine opportunity to close the loop on fashion waste.

Despite these benefits, recycled synthetics still shed microplastics during use, so washing carefully and choosing items that require minimal laundering are important to minimise pollution.¹⁰ When sourced from “true” waste rather than recyclables like plastic bottles (see below), they can still be a more responsible choice for synthetic clothing items.

Top 8 Most Unsustainable Fabrics to Avoid

Unfortunately, nearly all of the most common fabrics used for clothing feature in the unsustainable fabrics list. It’s not always possible to avoid these entirely, but being aware of them can help you choose more sustainable alternatives.

1. Conventional Cotton

Despite being natural, conventional cotton is one of the most resource-intensive crops, earning it the nickname “the world’s dirtiest crop”.¹ It is grown using with heavy use of chemical pesticides and fertilisers, creating significant carbon emissions, energy use, and pollution. Cotton is also a naturally water-intensive crop, which is worsened by the reliance on chemicals and unsustainable farming practices. The cotton industry is also known for it’s social issues, from pesticide poisoning of farmers to bad labour conditions and underpayment (read more here).

Cotton is an amazing and versatile fabric, which is why it’s one of the most popular fabrics on the market. But to be sustainable, choose organic cotton, certified to be made with natural and fair trade methods.

2. Leather

Leather is an incredible material from the in-use perspective, since it’s natural, plastic-free, repairable, and can last for generations. It depends on your personal values whether you are bothered that it’s made from dead animal skin, but it’s undeniable that the environmental and social impacts of making leather unfortunately make it an unsustainable material.

Cattle farming drives deforestation, methane emissions, and high water use, while tanning the hides into leather often involves toxic chemicals that pollute waterways and harm workers.¹¹ Even “vegetable-tanned” or certified leathers aren’t always better, as most still rely on intensive animal agriculture.

Plastic “vegan” leather alternatives are usually worse since they are made from plastic (see below). There are newer plant-based options, made from natural waste products like pineapple skin or grape skin, which show promise but aren’t fully biodegradable yet.¹¹ If you love leather, the most sustainable choice is to buy second-hand, recycled, or make the most what you already own.

3. Cashmere

Cashmere is a soft, luxurious fibre made from the undercoat of cashmere goats. Many brands say the goats are gently combed, but in reality most goats are tied and combed with sharp metal tools which is painful and distressing.¹²

The demand for cashmere has led to overgrazing, causing land degradation which contributes to biodiversity loss and local climate change. The industry also relies on low-paid herders, many of whom struggle as grasslands become less productive.¹² If you love cashmere, choosing recycled or second-hand pieces is a far more sustainable and ethical option.

4. Fur

Fur has been used for warmth for centuries, but the modern fur industry makes it one of the least sustainable materials in fashion. Around 95% of fur comes from wild animals like mink and foxes bred on factory farms, confined to tiny wire cages where disease spreads easily, and killed through methods like gassing, electrocution, or being skinned alive.¹³

Environmentally, producing fur is also highly resource-intensive and polluting, as it requires enormous amounts of feed and releases harmful emissions. Also, processed fur is chemically treated with toxic substances, making it non-biodegradable and creating risk of poisoning to industry workers which often suffer bad labour standards.¹³For both ethical and environmental reasons, fur has no place in a sustainable wardrobe.

5. Silk

Silk is another complicated fabric, because while it’s natural and high-quality, most silk production has serious ethical and environmental costs. Making one kilogram of silk requires around 187 kilograms of mulberry leaves, using vast amounts of land, water, and fertiliser, while coal-powered facilities create high greenhouse gas emissions.¹⁴ To produce the long, unbroken threads, silkworms are usually boiled or steamed alive in their cocoons, with around 5,500 needed for each kilogram of silk.

Labour exploitation is also common in major producing countries, where child labour and unsafe working conditions are widespread.¹⁴ Even “peace” or “ahimsa” silk, marketed as cruelty-free, still involves breeding and discarding moths in harmful ways. The most common alternative, polyester satin, should also be avoided as they are just plastic. There are promising innovations in plant-based silks emerging, but currently not widely available. For now, the most sustainable choice is to buy silk second-hand and care for what you already own.

6. Vegan / Faux leather and fur

Faux or vegan versions of leather and fur are often seen as cruelty-free alternatives, but most are made from plastics like PVC or polyurethane. These shed microplastics, pollute waterways, and break down much faster than real leather or fur, creating more waste.¹⁵

Faux fur and vegan leather have also become fast fashion trends, with cheap, poor-quality items flooding the market. While new materials like pineapple leather, cork, and mushroom leather show promise, they are still hard to find.¹⁵ The best option is buying real fur or leather second-hand, choose quality pieces, and look after what you already own.

7. Viscose Rayon

Viscose is third most popular clothing material after polyester and cotton, and often marketed as a more sustainable version of both, which is mostly untrue.¹⁶The term rayon is often used interchangeably with viscose, though rayon essentially the overarching term of cellulose based fabrics.

This fabric is made from regenerated cellulose fibres made from wood pulp from fast-growing trees and sometimes plants like bamboo. Because these are natural sources, it’s often marketed as sustainable, but the production involves toxic chemicals that are polluting and harm workers. Also, the wood is often sourced from unsustainable logging and contributes to deforestation due to the high demand.¹⁶ So, avoid viscose and instead opt for the more sustainable versions like lyocell and modal, as listed earlier.

8. Polyester, Nylon, Acrylic, and other Synthetics

All synthetic fabrics are plastic made from fossil fuels and have the same major problems for the environment. Synthetics don’t biodegrade, shed microplastics, and rely on energy-intensive, polluting production.¹⁷

Polyester is loved by the fast fashion industry and is found in everything from everyday clothing to fleece. Nylon production releases potent greenhouse gases and requires large amounts of water and energy, while acrylic is often used as a cheaper alternative to wool. PVC is also highly toxic to make and dispose of.

If you already own synthetic clothing, keep it in use as long as possible but wash in a microfibre-catching bag. But when buying new, natural or recycled bio-based fabrics are a far better choice for people and the planet.

9. Recycled Synthetic Fabrics (Mostly From Plastic Bottles)

Recycled synthetics like recycled polyester, nylon, and others can be sustainable (which is why it is also in my sustainable fabrics list), but many are used for greenwashing, so it’s important to know which versions to choose and what to avoid.

The main issue is that recycled synthetic fabrics still shed microplastics with every wash, contributing to ocean pollution and entering the food chain (read more about microplastics here).^{18, 19} Also, most recycled synthetics come from plastic bottles, disrupting the closed-loop recycling of PET bottles, which can be recycled repeatedly while synthetic clothing cannot.²⁰Production is often energy-intensive and uses blends with virgin plastics, keeping the environmental impact high.²⁰

These fabrics are best avoided for everyday clothing. Limit them for items that rely on synthetic qualities and require minimal washing, like coats or shoes. When possible, prioritise fabrics made from “true waste” such as fishing nets or textile scraps.

Final thoughts

No single fabric is perfect, but learning what’s behind the materials we wear helps us make better decisions. Choosing organic or recycled options, buying second-hand, or investing in long-lasting natural fibres all reduce the impact of our wardrobes.

The sustainable fabric options are generally more expensive than the unsustainable ones, but don’t let that affect your choices. When a fabric or garment is cheap, it is because someone else paid the price: the environment and the workers who make the fabric. Follow slow fashion principles by choosing a smaller selection of sustainable and durable clothing, instead of having a huge wardrobe of cheap, fast fashion garments.

When we buy less, choose carefully, and look after what we already own, that’s when fashion truly becomes sustainable.