Pick up a pair of jeans from any fast fashion retailer today. They stretch. Not because denim stretches—it does not—but because 2 to 5 per cent of that garment, invisible on the care label and rarely discussed in sustainability reporting, is elastane.

Elastane, also marketed as Lycra or spandex, is a polyurethane-based synthetic fibre with one exceptional property: it returns to its original shape after being stretched. For garment manufacturers, that property solved several commercial problems simultaneously. A stretch-blend fabric fits a wider range of body shapes, holds its silhouette after repeated wear, and reduces the precision required in cut and construction. Margins improved. Return rates fell. The stretch jean became the default jean. And then stretch entered shirting, formalwear, school uniforms, and occasion wear, i.e., categories where it had no functional justification beyond the commercial logic that had already made it standard elsewhere.

The industry did not design for what would happen to these garments at end of life. That question is now arriving: from recyclers whose systems cannot handle blended feedstock, from EU regulations that are embedding recyclability into market access conditions, and from a circularity investment cycle that is discovering, at scale, that comfort-optimised garments and circular textile systems are structurally in tension.

The Technically Accurate Misleading Claim

When a garment label reads ‘97 per cent cotton, 3 per cent elastane,’ the consumer, and often the brand’s own sustainability team, understands it as essentially a cotton garment. That reading is technically accurate. It is also commercially misleading.

Mechanical recycling, the most commercially mature textile recovery pathway, depends on relatively uniform fibre feedstock. Elastane behaves differently from surrounding fibres under mechanical stress: the elastic component stretches rather than fractures, shortening average fibre length, reducing yarn quality in the output, and lowering the commercial value of recovered material.1,2 Recyclers call this a contamination problem. It is more precisely a design problem that was never part of the original design brief.

Chemical recycling, which involves dissolving fibres back to their molecular components, can in principle address blended textiles, but requires separate process streams for each fibre type. No commercially scaled process yet handles polyurethane-based elastane economically alongside cellulosic and synthetic streams.3 The result is that the industry is investing heavily in textile-to-textile recycling infrastructure precisely as the feedstock entering that infrastructure becomes more materially complex.

Fashion for Good’s Stretching Circularity initiative (the most comprehensive industry effort on this specific question) has identified elastane as one of the sector’s most persistent technical barriers to textile recovery.4 That finding is significant not just as a material science observation, but as an indictment of the design decisions that put elastane into garment categories where it was never functionally required.

The industry is investing in the infrastructure to close the loop. The materials entering that loop are becoming harder to close.

The Industrial Knowledge Europe is still Discovering

Panipat cluster in India’s Haryana has processed post-consumer textile waste into shoddy yarn and blankets since the 1980s.5 The processors there will give an unambiguous operational answer to the elastane question: stretch blends reduce recovery rates, require manual pre-sorting to isolate elastane-dominant components, and yield lower-quality output that commands lower market prices. This is not research finding. It is twenty years of pricing and operational experience.

India’s PET recycling infrastructure tells the same story from a different angle. The Central Pollution Control Board reports PET recovery rates exceeding 90 per cent6, a figure built on mono-material or near-mono-material feedstock. The moment blended materials enter the stream in significant volumes, that recovery rate degrades. Thelesson from Panipat is not that India has solved textile circularity. It is that industrial systems closest to material recovery have understood for decades which materials resist it. Elastane has consistently been among them.

The EU is now encoding the same conclusion into legislation. The difference is that Europe is doing it through regulation rather than through the operating economics of informal recycling networks. The outcome, for manufacturers and exporters supplying European markets, will be the same: materials that complicate recovery will carry a cost.

What EPR Pricing Changes for the Stretch Calculation

The EU’s revised Waste Framework Directive requires Member States to implement Extended Producer Responsibility (EPR) schemes for textiles.7 Under EPR, brands placing garments on the EU market become financially responsible for the end-of-life management of those products. Waste management costs move from municipal systems into brand cost structures, embedded in pricing, product design, and material selection decisions.

France’s EPR scheme for textiles, operational since 2007 under REFASHION (formerly Eco TLC), already differentiates eco-modulation fees based on recyclability criteria.8 Products that meet recyclability standards pay lower fees. Products containing difficult-to-recycle components, like elastane-blended fabrics, pay more. The Ecodesign for Sustainable Products Regulation (ESPR), active from 2024, extends these principles across the EU market.9 The Digital Product Passport, mandatory under ESPR, will require disclosed material composition at a level of specificity that makes the 3 per cent elastane in a nominally cotton garment visible to every point in the supply chain, including customs and compliance officers.

This is the mechanism that changes the calculation. The comfort premium that elastane offers at point of sale is a liability at point of disposal. Under EPR, that liability accrues to the brand, not the municipality. The stretch jean that costs marginally less to manufacture because it requires less precision in construction may cost measurably more to place on European shelves once EPR eco-modulation fees are fully implemented.

The era of adding elastane everywhere without accounting for where it goes is ending. Not because the industry decided to stop. Because the regulatory framework is making the downstream cost visible.

Material Intentionality as the Missing Design Brief

The deeper question is not whether elastane should exist. In performance wear, compression garments, medical textiles, and adaptive clothing, elasticity is a functional requirement with clear user benefit. The problem is not the material. It is the absence of intentionality in the decision-making that put it everywhere else.

Fast fashion accelerated this indiscriminate diffusion. Once stretch became standard in denim, the commercial logic carried it into formalwear, occasion wear, and school uniforms—categories where the body does not require the fabric to adapt, and where the garment’s expected service life and end-of-life pathway were never part of the design brief. The industry normalised an expectation and embedded a systemic problem into billions of garments annually.

The Ellen MacArthur Foundation’s circular design framework articulates the corrective principle directly: recyclability must be a design criterion established at the outset, not a problem assigned to waste infrastructure at the end of the product lifecycle.10 For the textile industry, that principle translates to a straightforward set of questions that are rarely asked before a material decision is made: Does this product category require stretch? If so, at what percentage? What does that percentage do to the product’s recyclability? And who, under the EPR framework we are moving towards, will pay for that consequence?

Material literacy, i.e., the ability to understand what fibres actually are, how they behave across their full lifecycle, and what their presence in a blend means for downstream systems, is not currently a standard part of product development briefs, sourcing decisions, or sustainability reporting in most fashion businesses. It should be. The cost of that gap is not abstract. It is measurable in the recycling yield rates at Panipat, in the eco-modulation fees at REFASHION, and in the compliance exposure that ESPR is creating for every brand supplying the European market.

The Structural Question

The garment that stretches to fit is about to stretch something else: the cost model of the brands that make it and the recycling infrastructure of the industry that has to manage it.

The question for manufacturers, sourcing managers and product developers is not whether to eliminate elastane, but whether every product that currently contains it actually needs it—and whether the commercial rationale for adding it can withstand an honest accounting of its downstream costs.

The industry-built systems optimised for speed, fit and volume. It is now building systems optimised for recovery. The problem is that the same material decisions that made the first set of systems efficient are making the second set harder to build. Recognising that tension in the fibre decisions made at the start of a product’s life is where the correction must begin.