What Is 'Sustainable Underwear'?

Why we need a sustainable underwear revolution

In today’s fast-paced world of fashion, where trends change overnight and garments are often worn only a handful of times, the environmental impact of our clothing habits has become impossible to ignore.

The fashion industry is one of the most polluting industries globally, contributing to around 10% of global carbon emissions, generating 92 million tonnes of textile waste annually, and consuming vast amounts of water, energy, and resources. Nowhere is this more evident than in the fast fashion model, which sees cheap, mass-produced garments churned out at breakneck speed, a significant proportion of which end up in landfill sites within months.

Underwear is no small part of this problem. Modern, mass-market underwear production relies heavily on cheap, low-quality fabrics (resulting in low-quality, 'throwaway' garments) and wasteful, high-volume manufacturing processes - a combination responsible for a huge amount of waste and pollution.

But there is a better way. Sustainable underwear - and by extension, sustainable lingerie - is a growing movement that seeks to address these issues through thoughtful design, responsible sourcing, eco-friendly production, and a commitment to long-term durability.

In this post, we’ll explore exactly what makes underwear 'sustainable', examining:

• Responsible production: made-to-order vs. ready-to-wear processes, waste minimisation, and circular design principles
• Sustainable fabrics and other garment components
• Holistic approaches to sustainability across business operations

These key factors are the focus of those sustainable underwear and lingerie brands at the forefront of driving real change in the fashion industry.

'Sustainability' - a quick note on the terminology

Before we get started, we should pin down exactly what we mean by the term 'sustainability' in the context of the business of fashion.

Whereas some use the term 'sustainable' to refer primarily (or even exclusively) to environmental concerns - using resources responsibly to ensure that future generations are able to meet their needs, whilst also working to protect the natural environment more widely - for others it has a wider meaning, also integrating the concepts of social equity, social justice, and economic well-being.

Whilst we embrace that wider definition at ColieCo, for the purposes of this article, we're going to focus in on the environmental aspects of sustainability. (We've covered the social and economic factors addressed by sustainable fashion in sister post, What Is 'Ethical Underwear'?)

1. Responsible production models: slow vs. fast fashion

The mode of garment production any given fashion brand chooses to employ plays a critical role in determining the environmental impact of their operations.

The (colossal) elephant in the room: made-to-order vs. ready-to-wear fashion

At the heart of sustainable underwear production is the slow fashion model, and the exemplar approach is made-to-order garment manufacturing.

Unlike the mass-produced, ready-to-wear bras and undies offered up by both traditional brick-and-mortar and most modern online brands, made-to-order garments are only produced when a customer places an order.

This approach drastically reduces waste in several key ways:

• Eliminating overproduction: With a made-to-order process, there's no surplus inventory sitting in warehouses, no clearance sales, and ultimately, no unsold stock ending up in landfills. Some studies have found that up to 30% of ready-to-wear clothing produced can be left unsold. Employing a made-to-order model immediately eliminates all potential waste resulting from overproduction. 
  
  
• Cutting efficiency: As pattern pieces are cut only when needed, made-to-order processes allow for their strategic placement on fabric rolls, massively reducing offcuts and fabric remnants. In lingerie production - and particulary bra construction - where pattern pieces are often very small, it can even allow for offcuts to be saved to be used when cutting smaller pieces in future.
  
  
• Line-end elimination: Large-scale, ready-to-wear production runs often result in significant quantities of fabric being left at the end of fabric rolls. This leftover fabric, which is commonly discarded with factory floor waste, is known in the industry as 'line ends'. Not only can a made-to-order model eliminate line ends - which alone can account for up to 10% of all fashion textiles produced - it can even rescue and make use of ready-to-wear line-ends, mitigating the waste created by ready-to-wear brands. 

When the waste created across the various stages of the ready-to-wear model is considered in sum, it quickly becomes evident that the distinction between the made-to-order and ready-to-wear production models is the most important factor in determining the amount of textile waste a brand is likely to produce.

This means that electing to employ a made-to-order model is maybe the most significant choice a sustainable fashion brand can make in seeking to minimise the environmental footprint of its operations, and by extension, its garments.

(For a deeper dive into how slow fashion can eliminate waste, see our in-depth blog post here.)

Small batch production

Middle ground can be found in small batch production processes. In this approach, brands produce limited quantities of each garment at a time, allowing them to test demand before committing to 're-issues'.

While this model will still inevitably result in some overproduction, it can significantly reduce waste compared to large-scale manufacturing. 

Customisation: made-to-measure undies

With our underwear - and especially with lingerie - fit matters. Yet mass-produced garments often fail to cater to the diversity of real bodies. A made-to-order approach to garment manufacturing also enables made-to-measure services, as well as other after-sales offerings, like alteration and repair services.

Made-to-measure services, creating lingerie tailored to the individual’s measurements, not only help deliver a better fit, but in doing so they also reduce returns and waste. Similarly, alteration services encourage customers to keep and adapt their garments, rather than replacing them. And repair services (such as offering mending services for broken straps and loose elastics) can significantly extend garments' lifespans and help build a culture of care and appreciation for clothing.

These services contribute to a longer, more personal relationship with our underwear, helping us move away from a culture of disposable fashion and instead towards a 'wear, care, and repair' mindset.

Designing for longevity and circularity

Another critical element of ethical underwear is thoughtful design - creating pieces that transcend seasons, are built to last, and consider their end-of-life from the beginning.

• Durability: Sustainable lingerie should be made to withstand regular wear and washing. This includes choosing high-quality, long-lasting fabrics and other garment components, and investing in robust stitching methods and quality craftsmanship.
  
  
• Longevity: Rather than chasing fleeting trends, sustainable underwear designs favour timeless styles that remain wearable across seasons. With underwear and lingerie, which are worn snug to the body and also used to provide support, the creation of highly adjustable designs can help ensure that garments remain wearable - and comfortable - as body shapes and sizes change over time.
  
  
• End-of-life planning: Circular design principles consider what happens when a garment is no longer wearable. Can it be recycled, or can it be safely composted? Mono-materials (fabrics without mixed fibres) or easily separable components can help make these ends possible.

By designing with both beauty and practicality in mind, sustainable underwear can be a joy to wear for months and even years, rather than the few short weeks offered by fast fashion's cheaper alternatives.

2. Responsible materials: sustainable fabrics and components

Sustainable underwear brands often focus their commitment to the planet on another important decision: fabric selection. But choosing the right textiles is about more than just using 'natural' fibres - it’s about the sustainability of the entire supply chain, from raw material sourcing to dyeing and finishing.

Sustainable fabric options

Let’s break down the three key categories of fabrics used by sustainable underwear and lingerie brands:

Botanic-origin fabrics

These are fabrics made from fibres derived from natural plant sources. Although there can be a tendency to look at natural fabrics as inherently more sustainable than synthetic fabrics, many natural fibres widely used in the production of underwear carry heavy environmental footprints.

Cotton, for example, relies heavily on chemical pesticides and fertilisers and tends to have a huge transport footprint, as the various stages of cotton fabric production - including baling, cleaning, carding, spinning, weaving, and finishing - are often undertaken in different countries, sometimes even on different continents. And even organic cotton farming practices rely on relatively incredibly high water consumption. So while cotton is an inherently renewable resource, the end-to-end production of cotton fabrics poses considerable environmental challenges. 

Some of the more environmentally friendly options often chosen by sustainable underwear brands include:

• TENCEL™ Lyocell and Modal: These cutting-edge fabrics are derived from fibres extracted from wood pulp, using a closed-loop process that recycles both water and safe solvents. Wood is an exceptionally renewable resource, and, unlike cotton, doesn't require pesticides, herbicides, fertilisers or, critically, irrigation to grow. Lyocell and modal are soft, breathable, and biodegradable, and have become staples as cotton alternatives in underwear production.
  
  
• Bamboo: When processed mechanically or in closed-loop processes (recycling the water and the solvents used to break the raw material down), bamboo can be a highly sustainable option. It grows quickly, and like wood, requires no pesticides or fertilisers and relatively very little water to grow.
  
  
• Hemp: Hemp is a textile made from the fibres of the Cannabis sativa plant's stalks, and is known for its durability and strength. Hemp fabric has a long history of use, dating back thousands of years, and has gained popularity in recent years as another sustainable alternative to cotton in the production of underwear.
  
  
• Organic cotton: Despite the challenging issues with its water consumption and transport footprint, organically grown cotton remains a popular choice with sustainable underwear brands. As we'll see later, it’s important to ensure that cotton garments sold as sustainable options are made from GOTS-certified fabrics which have been processed with care.

Recycled fabrics

These fabrics are textiles made from repurposed materials like plastic drinks bottles, old clothing, fabric scraps, or even discarded fishing nets, rather than newly produced (or 'virgin') materials. Recycled fabrics can reduce waste in landfills and minimise the need for new resources, contributing to a more sustainable fashion model.

While naturally soft and highly-breathable botanic-origin fabrics like lyocell and modal can be excellent choices for eco-friendly everyday underwear, they don't offer the technical or aesthetic properties which might make them suitable substitutes for nylon or polyester - the staple fabrics used in lingerie production.

Instead, materials like recycled nylon and recycled polyester - which can offer figure-hugging elasticity, an eye-catching sheen, and differing degrees of translucency - can be used in place of their virgin alternatives, whilst reducing reliance on virgin petroleum and diverting waste from marine environments and landfills.

Reclaimed/upcycled fabrics

Maybe the most sustainable category of textiles used in slow fashion comprises fabrics reclaimed from the rolls and line-ends wasted by the mass production processes of the fast fashion industry. Using reclaimed fabric not only requires no new resources; it actively prevents existing, valuable resources from going to waste.

Although an obvious environmental win, using reclaimed fabrics poses various challenges for sustainable brands: sourcing, selecting, and tracing rejected rolls and line-ends is difficult and time-consuming, and there are often very limited runs of fabrics available, meaning limited lines and greatly reduced benefits of scale.

But the careful and creative use of reclaimed fabrics allows slow fashion brands to reduce demand for new materials and offer garments with relatively tiny environmental footprints.

Other fabric considerations

Creating truly sustainable fabrics isn’t just about fibre content; it’s also about minimising the material's transport footprint across the end-to-end production process, low-impact dyeing and finishing, and responsible fabric use.

Transparency in the supply chain is essential to ensure that each step aligns with the principles of responsible production, and sustainable underwear and lingerie brands will provide detailed public information on these elements of their processes. (At ColieCo, we've pledged that each and every one of the fabrics we'll ever use is either made from an inherently sustainable and sustainably processed natural fibre, a certified recycled fabric, or a reclaimed fabric. You can find out more about each and every fabric we're currently using here.)

Better choices for every component

Ensuring a sustainable use of resources doesn't begin and end with the fabrics brands choose to use. All underwear and lingerie production includes the use of other garment components, such as elastics, underwires, hooks, and sliders. Small though they may be individually, these components can add up to a significant environmental impact if not sourced responsibly.

Elastic, for example, is a crucial component in underwear and bras, yet it’s often made from virgin synthetic materials manufactured in poorly-controlled, environmentally-damaging processes. More sustainable underwear and lingerie brands look to source elastics made from natural rubber blends or recycled synthetics, or which have been produced in environmentally-certified facilities.

Even the smallest details like thread and labels really shouldn't be overlooked. Opting for organic cotton or recycled polyester thread and using compostable or recycled content for labels can help ensure that every part of the garment stays true to ethical standards.

Fabric and garment certification

In an age of widespread corporate greenwashing, an important question is: how can consumers be sure that the fabrics and processes used by brands claiming to be offering eco-friendly underwear are legitimately sustainable? This is where independent certifications come in.

Recognised third-party standards can help verify environmental (as well as ethical and health-related) claims across a brand's supply chain, offering reassurance to customers that what they’re wearing truly aligns with their values.

Let's take a look at some of the most reputable certifications commonly seen in the sustainable underwear and lingerie domain:

GOTS

One of the most well-known standards used to certify fabrics of botanic origin is the Global Organic Textile Standard (GOTS). GOTS is a comprehensive certification that ensures textiles are made from organically-grown fibres and processed without the use of harmful chemicals. It also verifies responsible labour practices throughout the production chain. For ethical underwear made from organic cotton, GOTS is considered the gold standard.

ECOCERT

ECOCERT is another respected certifier that audits textiles for organic and ecological integrity. ECOCERT verifies adherence to both organic farming standards and environmentally friendly manufacturing practices. It is widely used in Europe and is recognised for its strict criteria, particularly around biodegradable inputs and waste management.

GRS

Another important label is the Global Recycled Standard (GRS), which applies to products made from recycled materials, including fabrics like recycled nylon and polyester. GRS not only confirms the percentage of recycled content in a product but also assesses social and environmental practices, chemical restrictions, and chain-of-custody requirements. For lingerie made using recycled fabrics, GRS is considered the gold standard certification.

OEKO-TEX® STeP

The OEKO-TEX® STeP (Sustainable Textile & Leather Production) certification evaluates production facilities, rather than fabrics alone. STeP focuses on sustainable manufacturing processes, fair working conditions, chemical management, and environmental performance. If a brand invests in textiles produced in OEKO-TEX STeP certified factories, it means they're investing in cleaner, safer production methods down their supply chain.

SANE Standard

Lastly, the SANE Standard is a newer but highly innovative framework that emphasises complete transparency in textile production. SANE is an holistic standard built around sustainability, ethical labour, responsible chemical use and transparency, giving brands and consumers full insight into how garments are made - from farm to finish.

The SANE Standard, which is awarded to both garment production facilities and products alike, requires sustainable underwear and lingerie brands to take responsibility for the social and environmental impacts of every step in their supply chains. (At ColieCo, we're incredibly proud to be able to say that our garment production facility and all of our lingerie and underwear sets, bras, panties, bodysuits and swimwear are SANE Standard certified. Learn more here.)

Together, these certifications play a critical role in distinguishing truly ethical lingerie from greenwashed products. When you see garments certified by one or more of these standards, it’s a strong indication that the brand is committed to real, measurable sustainability, and not just marketing buzzwords.

3. An holistic approach to sustainability

Beyond the garments themselves, truly sustainable underwear brands take a holistic approach to sustainability across their business operations. That means integrating eco-conscious decisions at every level of the business.

Energy use

Energy consumption in manufacturing, commercial and retail facilities is a direct contributor to a brand’s carbon footprint. Fashion brands committed to sustainable practices are increasingly turning to renewable energy suppliers and contracts to power their studios, offices, and stores. By doing so, they can significantly reduce reliance on fossil fuels and contribute to a cleaner, more responsible supply chain.

It’s not just about the energy source, though - it’s also about how efficiently that energy is used. Energy-efficient machines, LED lighting, and natural air conditioning can all play a role in limiting emissions and keeping operations lean. Over time, these measures not only benefit the environment but also reduce long-term operational costs, making ethical manufacturing more economically viable.

Additionally, brands may offset unavoidable emissions through carbon credit programs, supporting reforestation, renewable energy projects, or other environmental initiatives. 

Water management

As we've seen, water is another critical resource in fashion manufacturing, especially in the cultivation of crops and during fabric processing, dyeing, and finishing. But forward-thinking eco-friendly brands implement water-saving techniques and infrastructure throughout their end-to-end processes, from choosing fabrics made from fibres processed in closed-loop water systems to installing low-flow and short-flush devices in their own facilities.

Packaging

A growing proportion of consumers recognise that sustainable packaging has a significant role to play in reducing a brand's environmental impact. Many sustainable fashion brands now use plastic-free, and recyclable or compostable packaging to eliminate unnecessary waste. Some go further by incorporating packaging made from post-consumer recycled materials or agricultural waste, creating a fully circular solution.

Thoughtfully designed packaging is also minimal. By keeping packaging light and efficient, brands not only reduce material consumption, but also cut down on emissions from transportation. 

The use of eco-conscious packaging helps ensure that sustainability doesn’t stop at the product itself. When your eco-friendly underwear arrives in recyclable or biodegradable materials, the experience aligns with your values from start to finish.

Shipping

The logistics of shipping raw materials, textiles, and garments around the world contributes heavily to the fashion industry's carbon emissions.

To help address this problem, sustainable brands aim to partner with regional or local suppliers to help reduce emissions. Some brands prioritise working with fabrics produced closer to their garment production facilities, or garment production facilities closer to their customer base, allowing for shorter shipping distances and a smaller carbon footprint.

Many eco-conscious brands also offer carbon-neutral shipping options by partnering with services that offset transportation emissions through reforestation or renewable energy projects. Choosing airmail freight over courier-run freight services, and even bicycle couriers for local deliveries, are other ways that ethical brands are making logistics more sustainable.

In summary: what makes underwear 'sustainable'?

Sustainable underwear and lingerie is about rethinking everything we’ve come to expect from fashion. It’s about making fewer, better, longer-lasting things. It’s about reducing the colossal amount of waste created by the established, mainstream fast fashion industry. It's about choosing greener materials and treating them with care and respect. And it's about taking a step back to consider the wider and longer-term impacts of even the seemingly most insignificant steps in the process.

From slow, made-to-order production and thoughtful design for durability and circularity, to better materials and an holistic approach to improving processes and practices, sustainability in the business of fashion is as multifaceted as it is desperately necessary.

At its core, sustainable underwear is a commitment: to quality over quantity, to mindfulness over convenience, and to a future where fashion doesn’t cost us the earth.

At ColieCo, we're serious about each and every one of those factors listed above. You can learn more about our commitment to sustainability here, our SANE Standard certification here, and each and every one of the fabrics we use here.