Founder Stories

OLIO founder Tessa Clarke: Lessons from building the UK’s top sharing platform

Founder Stories

OLIO founder Tessa Clarke: Lessons from building the UK’s top sharing platform

March 28th 2024 / 8 min read

Consumers are confronted with a number of lifestyle decisions to help reduce their carbon footprint. These range from buying electric vehicles, to replacing meat with plant-based food, to limiting plastic waste through reusable products. 

For Tessa Clarke, the one of the most important consumer choices you can make to save the planet is simple: don’t waste food. Around a third of all food produced for human consumption goes to waste. If food waste were a country, it would be the third largest source of human carbon emissions. 

Tessa’s awareness of the vast food waste problem drove her to think of creative solutions for everyday consumers, an idea that has grown into OLIO, the largest food sharing app in the UK, which she co-founded with Saasha Celestial-One. OLIO is a marketplace-social network facilitating local communities to share food or belongings that would otherwise end up in landfill. 

Since launching in 2015, OLIO has captured the attention of consumers, large corporations, and investors alike. They’ve gained over five million users across 59 countries, launched partnerships with Tesco and Pret a Manger, and raised over £11 million in financing. 

Excerpted below, and in her own words, Tessa revealed the story of building OLIO in a recent Founders Factory fireside chat, including some of the most valuable lessons she’s learned along the way, including:

1. Don’t stay tied to your hypothesis—continually test and validate 

2. Growth and engagement should come before monetisation

3. Be aware of the unintended consequences of your product 

4. Changing consumer behaviour is a long, challenging process  

5. Consumers, startups, and corporations all have a role to play in driving change

You can watch the full fireside chat with Tessa here.

Food waste by numbers

  • 1/3 of all food produced globally goes to waste

  • $1 trillion is the value of food wasted annually around the world

  • 25% of the world’s fresh water supply is used to grow food that is never eaten

  • An area larger than China is used to grow food that is never eaten

Lesson 1: Don’t stay tied to your hypothesis—continually test and validate

Having grown up on a farm, and seeing the work that goes into producing food, food waste is always something that I’ve been acutely aware of. The tipping point for me was when I was moving house: the removal men said that any uneaten food had to go in the bin, and there was no easy way for me to let my neighbours know that I had all this food that was going to waste. 

I got my former Stanford MBA classmate Saasha on board, who shared the same aversion to things going to waste. I knew she’d be the perfect partner to help launch OLIO. 

We started by deeply researching the problem, quickly identifying that half of all food waste in the UK was happening in the home. It was a problem that individual consumers could change, but just didn’t have the framework or the critical mass to do effectively.  

Saasha and I formed the hypothesis that food sharing might have been the solution: but as with any problem solving, we did ask ourselves "what are all the other ways this problem could be solved?". As an entrepreneur, it's important to be prepared for this, as your number one solution may not always be the right one.

We also considered:

  • Education - The government had invested in this, and it had fundamentally failed

  • Smart fridges - These were expensive and would take a long time to get to scale.

Next, we went to consumers. Off the back of an initial Survey Monkey, we formed a proof of concept Whatsapp group with just 12 people to see whether our food sharing solution actually worked. They all lived in the same area, none of them knew each other, and we said: “Share any food that’s going to waste.”

Reflecting back, this was our minimum viable product (MVP). We learned through this MVP that the idea worked (they all loved the concept of sharing food to prevent waste), and secondly, that it didn’t need to be any more sophisticated than that Whatsapp group. This was a great proof of concept: we didn’t need to spend time developing sophisticated technology, user profiles, reviews, and ratings, it just needed to be slightly better than Whatsapp. 

We’ve kept this ‘MVP’ mindset with us ever since. Food sharing is a simple enough idea, and there’s no need to overly complicate it beyond the bare bones of what the original Whatsapp group provided. 

Lesson 2: Growth and engagement should come before monetisation

It’s tempting to prioritise monetisation of your product: more than anything, this makes it far more viable to investors. On the contrary, we prioritised growth and engagement before monetisation. 

We knew OLIO would only work once it reached scale. We had to gain a critical mass of users before sharing could take off, and we didn’t want to jeopardise reaching that in order to make money. Having prioritised growing our community, we’ve been able to better understand the full landscape of where we’re creating value, which will then allow us to understand how and what to monetise. 

Our Food Waste Heroes program is the perfect example of that—something we would have never conceived of had we followed typical monetisation models. We connect supermarkets and cafe chains, who are giving away large amounts of excess food, to volunteers who then upload all this to the platform. Here, there’s immense value in preventing supermarket waste that would ordinarily end up in landfill: and the fact that we can monetise, too, is a huge advantage.

Not prioritising monetisation created additional challenges for us when it came to seeking investment, especially as female founders who notoriously come up against many biases—one of which is a perceived reluctance to commercialise. 

Tessa’s tips for combatting investor bias:

Answer “prevention” questions with “promotion” responses

  • Female founders are more likely to face “prevention” questions (focusing on downsides or possible failures). Try to respond to these types of questions with “promotion” responses (focusing on successes and ambitions). 

Over-index on commerciality

  • Counter the bias that you aren’t commercially-driven by putting your numbers and figures up front in your pitch deck

  • If, like us, you aren’t monetising, focus on user numbers and growth

Display your ‘seals of approval’

  • Saasha and I realised early on that, if we were to be taken seriously, we’d need to display our achievements clearly, whether that was our Stanford MBA, or previous employers like BCG

Lesson 3: Be aware of unintended consequences of your product

With any new technology product, you have to be aware that there may be unintended consequences. For instance, we’ve often been pointed towards tackling food poverty. Food poverty is a huge issue, but unfortunately isn’t one that can be solved by food sharing. We’ve come under pressure to divert food towards homeless shelters, for instance: but that’s not the issue we’re trying to solve, and it’s important not to lose sight of our actual mission. 

Another unintended consequence that we’re wary of is people becoming dependent on getting food from OLIO. We try to limit how much people can access through the platform, and we also work on signposting other services to that small number in our community who may be vulnerable. 

Founders must acknowledge unintended consequences upfront, and be prepared to tackle and address these when they arise, without getting distracted. A good way to do this is to remind yourself of your ‘North Star’—the fundamental reason behind your product.

Lesson 4: Changing consumer behaviour is a long, challenging process

Sharing food isn’t a new concept: in fact, it’s a very established human behaviour, and one of the main reasons why humans have been so successful as a species. And yet the idea of sharing food with complete strangers still feels unnatural and counter to consumer behaviour. We knew we had a big task in trying to impact and shift human behaviour in order for OLIO to be a success. 

After reading a lot of behavioural psychology books, one of the main things we learned is that the biggest determinant of consumer behaviour change is when someone believes that everyone else is doing something else.

So we had to pay attention to all of the messaging we were using, constantly emphasising how many people were using OLIO in their area, how many people had seen their listing, and hammering home that point that this is the new norm. This is the power of social proof.

“The biggest driver of behaviour change is thinking everyone else is doing something else.”

We’ve already triggered a revolution around sharing food, and we hope this can go further. We’re launching new products, like OLIO Borrow and OLIO Made, which will allow people to borrow belongings from their neighbour or buy products that are locally produced.

Lesson 5: Consumers, startups, and large corporations all have a role to play in driving change

Everyone has a part to play in reducing carbon emissions. Startups have an incredibly important role with regards to driving innovation, as they have huge opportunities to pursue radical ideas. The dream, however, is when you combine this with corporates who have the route to market and the scale needed to drive change. 

It’s tempting to sit around and wait for that corporate partnership that will send you into the stratosphere—but these can be lengthy processes. It’s often worth starting small. We worked with smaller bakeries and cafes to begin with, to demonstrate that our model could work, before signing our first mainstream partnerships with brands like Pret a Manger and Tesco.

"Billions of small actions got us into this mess; so surely billions of small actions can get us out of it."

And don’t underestimate the power of the people. Consumers really need to recognise the power they have in driving change. Think of it like this: every pound you spend is a vote, you can vote to stick with the status quo, or you can vote for change. Bill Gates also cites ‘voting with your wallet’ as one of the most important things everyday consumers can do to encourage organisations to implement sustainability practises. This means that every decision you make, whether that’s buying a plastic bottle or a reusable one, or throwing away food or sharing it, can make a difference. 

Billions of small actions got us into the current environmental mess we’re currently in; so that means that surely billions of small actions can get us out of it. Our vision at OLIO is to reach one billion users: extremely ambitious, yes, but if we’re truly committed to our mission of creating a world that we can inhabit in the future, then that needs to happen. 

Tessa’s top recommended reads & podcasts



About Tessa

  • Tessa Clarke co-founded OLIO in 2015 with Saasha Celestial-One

  • Before this, she worked at Boston Consulting Group, before studying an MBA at Stanford

  • OLIO has raised $53 million to date, including a $43 million Series B led by VNV Global

    👋 Say hi to Tessa on Twitter

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