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What Happens to Old Tennis Strings?

December 5, 2025 Juan

Most old tennis strings end up in landfills where they'll remain for centuries.

With 25.7 million tennis players in the USA in 2025, that translates to more than 24 million pounds of polyester strings discarded annually across the country alone.

This massive volume of string waste creates a significant environmental challenge.

In this article, you'll discover why tennis strings are so difficult to recycle, what we’re doing about it, and what sustainable alternatives exist to reduce waste at the source.

The Environmental Cost

Polyester and multifilament strings are not biodegradable and can persist in the environment for over 500 years. While natural gut strings are biodegradable, they represent a small fraction of strings used due to their premium pricing.

Some players get creative by repurposing old strings as garden plant ties or craft materials. These individual efforts help, but they don't solve the larger problem. Almost all tennis strings eventually end up in landfills because recycling options remain extremely limited.

But why is recycling tennis strings so difficult?

Polyester and multifilament strings tangle in recycling machinery, jamming equipment and disrupting operations. Their small size and mixed-material composition mean few facilities can accept them. Even players who want to recycle responsibly often have nowhere to send their old strings.

These synthetic strings also release microplastics as they break down. When cut or frayed, tiny plastic particles enter soil and water systems, adding another layer to tennis string's environmental footprint.

ReString's Upcycling Program

We saw this waste problem and decided to do something about it.

ReString collects broken Zero and Sync strings that would otherwise head to landfills. We transform these used strings into unique upcycled keychains, giving them a second life beyond the court.

Each keychain set contains two pieces made from one racket's worth of string. The mixture of Zero and Sync creates color variations that make every keychain one of a kind. No two pieces are identical.

This upcycling initiative represents just one piece of our commitment to sustainability. You can explore the many sustainability projects we undertake at ReString, from carbon-neutral operations to biodegradable packaging design.

Reduce Waste at the Source

The most effective way to address string waste is preventing it in the first place. Instead of playing with virgin polyester strings, consider switching to recycled polyester strings like Vivo.

This approach differs from upcycling old strings but offers an even better path toward sustainability by preventing new plastic production through repurposing existing materials.

Vivo stands out as one of the first recycled polyester strings that delivers professional-level performance without compromising on sustainability.

Made from recycled polyester sourced from post-consumer plastic waste, Vivo proves that environmentally conscious choices don't require sacrificing the performance you need on court.

Conclusion

Old polyester and multifilament tennis strings aren't going anywhere anytime soon. Traditional recycling programs can't handle them, and municipal facilities aren't equipped to process small, mixed-material waste like tennis strings.

The good news? The tennis industry is starting to address this challenge. Upcycling programs are giving broken strings new purposes, and strings made from recycled materials are proving they can match the performance of traditional options.

At ReString, we're committed to both solutions while keeping your on-court performance as the top priority. Every string matters, and small changes in how we think about string waste can create meaningful impact over time.

About the Author: Juan is the co-founder of ReString. He was born in Argentina, raised in Japan, and moved to the US to pursue college tennis. He now plays as an ATP & WTA hitting partner.