#002 Kings of Indigo

Meet Tony Tonnaer, founder of Kings of Indigo. Worldwide one of the most sustainable, innovative and fair denim brands now moving to circularity. How do you build a healthy company in sustainable fashion? And how circular are these ‘Clean Jeans’ exactly? In this very open interview we asked him everything we were curious about.

This is Kings of Indigo’s story about sustainability and circularity in fashion. Highlights for you are:

  • The vision of this frontrunner entrepreneur, who chose purpose over profit to lead his company to one of the most sustainable denim brands in the world
  • The biggest challenges and opportunities in the fashion industry, and how to innovate within the ecosystem
  • What it takes to create a ‘Clean Jean’
  • Do’s and don’ts if you want to incorporate circularity in your business

Watch his Circular Story here!

1. Tony, what does Circular Economy mean to you?

“Circularity to us, means focus at minimizing the use of new resources as input for our jeans plus minimizing waste in the entire production proces. Our vision is to design quality products that just last longer. This requires circular thinking in every step of the proces and during the life cycle; facilitating repair, reuse and recycling at the end of life. In this way we create a closed loop system where materials will circulate and be used over and over.”

2. Can you tell us more about Kings of Indigo and your business model?

“Kings of Indigo creates sustainable denim and fashion for the medium high global market. Our brand is built on 5 pillars that you will find back in everything we do, and the result is the ‘Clean Jean’:

  1. Made with planet friendly materials
  2. Less water use
  3. Made in certified factories audited in Social Fairness
  4. Produced as close as home as possible, minimizes transport
  5. Waste consciousness, using recycled and recyclable materials

Our business model is based on production as close to home as possible, and distributing to stores in Northern Europe on a wholesale base. Direct online sales is approximately 15% of the total business, nowadays and we expect more growth in online and marketplaces for the next years.”

3. What is your Why?

“Denim in my DNA. As my father really knew how to dress well, with certain class and definitely owning his style, I was raised with a passion for fashion and quality clothing. Especially denim. Throughout my career I worked for several denim companies all doing the same: producing and pushing garments to retail and consumers, whilst ignoring the negative impact on our planet. With my fascination for innovation and ‘denim in my DNA’, I decided to found Kings of Indigo. Not to produce another jeans, but to show the industry by example that change is possible.”

“I always wanted to be two steps ahead, when it comes to being circular and sustainable.”

So, I gradually innovated the way it is done: Starting with optimizing use of raw materials and social compliance, adding water management, waste management and minimizing footprint in the next phases.”

Circular Quote
of the day:

“I always wanted to be two steps ahead, when it comes to being circular and sustainable.”

Tony Tonnaer

4. What would you say are the main circular principles to produce a ‘Clean Jean’?

Kings of Indigo’s story about sustainability and circularity in fashion is based on a few main principles:

Closing the loop by not letting waste be waste!

“60% of the input material for our jeans is recycled or rescued materials with a former life: we use the metal of former surgical instruments for buttons, and use waste streams of the denim production. Waste consciousness is key to circular entrepreneurship. We support clients during the use and at the end of life of the garments with recycle.”

Water management

“By innovating the process of dying denim with laser and washing them with recycled grey water, we reduced water use with up to 5.000L per pair of jeans. Next to using as little water in the raw material production of course.

Quality for the next era

“This drives us to make jeans from materials that simply last longer. Because of this, the residual value of the material in your jeans is €30 after 3 years wearing! With this circular perspective, these materials can go back into the loop again.”

5. How do you innovate with partners within the ecosystem?

“To produce a ‘Clean Jean’ partnerships are essential. From sourcing, to production, to warehousing, only by working together we can make it happen.

By requesting sustainable actions and materials from our partners I believe we inspired them to take steps to sustainable garments. When it comes to innovation, the most sustainable steps were taken by the mills, now developing more recycled and closed loop materials of good quality.

Together we have been able to create a different mindset, that nowadays also caters the rest of our industry. “

6. As a leader, what do you consider to be the main driver for your company: purpose or profit?

“I honestly can say it has been purpose over profit. We have invested in sustainability since 2011 and only this year (2020) we will achieve our first profit.

To many entrepreneurs this may seem crazy, but our mission reflects our personal drive and defines our business goals. Without this inner drive, vision and aligned leadership I would have given up long time ago and Kings of Indigo wouldn’t be where it is now. I see the world is changing and becoming ready to shift towards sustainable fashion. Our intent is to obtain a healthy profit and to re-invest directly in sustainable or circular innovations that help change the industry, which in turn helps us. This circular approach is fits our purpose well.”

How does that influence decision making and internal culture?

“Driven to be two steps ahead of the industry, we are continuously innovating and taking step in becoming even more sustainable. That means keep on track with the newest insights and technologies. This challenges our team a lot, and therefore it is of utmost importance that our internal company culture is defined by our inner drive and mission: we are doing this for ourselves, the planet and the people we love.

Within our small team of 14, one person is completely dedicated to CSR. Stimulating every one of us to keep circular thinking our top priority in every field of expertise.

We don’t like to think inside the usual boxes (sales, retail, production) but have a holistic approach for the collection as a whole: the entire collection for two seasons and all stock levels are grounded in the 5 sustainability pillars of KOI. We want to set an example in the industry, and create the transition to fair clothing with hardly any carbon footprint and no more landfills. We do hope that many will follow!”

7. Does circularity give you any opportunities or competitive advantages that other less sustainable companies don’t get?

“Absolutely! Firstly, leaning into a circular business perspective has made us more aware of what is happening with the planet and the urgency to change. This circular mindset makes us think twice about what we are producing, how we are producing and what happens with the garments once they go into the market. It forces us to think more long-term and out-of-the box; what new materials and technologies are available that can suit us, how can we reuse waste? How can we produce just-in-time? This continuous drive to innovate has led us to be one of the most sustainable brands out there. And now, mills and factories come to us to show their newest innovations and work together. This position enables us to pioneer even more! The denim industry is now giving us recognition for that, and we hope the consumer will follow.”

What is your challenge to become 100% circular?


Nowadays it is physically impossible to make a pair of jeans from 100% post consumer recycled cotton. These pants would simply break easily and thus cannot meet the quality standards we formulate at of Kings of Indigo.

To close the loop, we need to work towards a product which is easier to recycle as a whole. With easy removable metals, no zippers, another stretch fabric and create a logistic flow to collect obsolete garments from consumers, which with a wholesale structure is very ineffective and economical not viable yet.

8. In your experience, being a frontrunner entrepreneur, what are the biggest challenges?

“Of course I’ve encountered many barriers, some you can solve… others not. But once you solve them they tend to be enablers! I might say these barriers, could be general for other entrepreneurs too:

  • Lack of deep knowledge; about what a circular product is and how to develop and market it.
  • Creating margins and pricing; In the beginning we faced relatively high production costs, which made it difficult to penetrate the market with commercial prices while making a healthy margin. As more brands convert to circular products, we are able to create more volume, leading to costs coming down a bit. It’s always a balance between volume, margin and consumer pricing.
  • Consumer awareness; this really has to change, and we need to find ways to convince the consumer to consume differently.

The road has been partly paved, so nowadays it is easier to make the transition. As knowledge is more widely available at suppliers, circular products can be made for better prices than before, and you can position yourself as a brand of the future instead of the past.”

9. What bad recommendations do you hear in your area of expertise?

“The advice to make a separate line for circular products, while not changing the core of your business. Circularity then becomes a marketing tool that simply cannot bear the change of vision and culture from within which you absolutely need to survive.”

10. Any tips for other entrepreneurs?

“My advice would be: ensure and incorporate a circular economy perspective from the beginning of your company so you can kick it off right away!

If on the other hand, you have an established company and want to become more circular, do take small steps over time while making a longterm plan with realistic goals. Set goals each year and work towards them, always know what the next level of sustainability is and work towards it. Look for know-how to do it right.”

11. What changes have you recently made regarding your own personal lifestyle?

“I started eating less meat, and when I do only buy organic. We stick to a maximum of 3 days a week. And boy… I love good meat.”

12. Which initiative or project do you take pride in the most? And why?

“Oh, I do remember this very well! 5 years ago we launched the ‘Red Light Denim’, in cooperation with House of Denim. It was our first denim with post-consumer recycled cotton. All collected in Amsterdam and mixed with organic cotton and hemp. This was so innovative and efficient: in the end we saved 50% new cotton for the production of this jeans.”

13. What would it look like when it was easy?

“When know-how is available in the industry, consumers are open to consume in a different way and money was no issue the circular economy would be easy and I think way more companies would go this route.  This addresses the barriers I mentioned before (question xx).

If circularity was easy, the design process would be redesigned resulting in low impact production methods in all steps and reuse of all materials after a product served its purpose (end of life).

I believe nowadays more and more resources for any industry are becoming available and easier accessible. Not yet as a holistic approach, but in individual fields (raw materials, social compliance, water management, waste management, energy and CO2 footprint). It needs to be tied together somewhere in a total strategy and benchmark, like Cradle 2 Cradle.”

14. If you could have a gigantic billboard with anything on it what would it say and why?

15. What regarding our Circular Stories project, are you most curious about?

“I would like to see how you will tie circular stories from different industries together in a bigger message that will impact consumers and the industry to change our buying behavior.”

16. What do you hope to obtain with your Circular Story?

“We need more consumer awareness to create real impact! It is so much fun and interesting to think and consume differently. We hope that you can let them see that it is possible to choose a ‘Clean Jean’ with way less negative impact. Without making concessions to quality, coolness and price. Also, I would like to trigger investors to take this journey with us, seeing the long term benefits.”

Would you like to see the new collection?

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rethink the way we live, love, travel, work and do business.’
Ellekari & Mariëlle
Founders of Circular Stories

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