Member Spotlight: Meet Seb Stritt, the 21-Year-Old Founder Modernising Letterbox Marketing

At Urban Collective, we’re lucky to be surrounded by founders who are building incredible businesses – and Seb Stritt is no exception.

At just 21 years old, Seb is the founder of Realrun, a technology platform transforming one of Australia’s oldest marketing channels into a modern, data-driven solution. Often described as “Uber for letterbox drops,” Realrun connects businesses with a nationwide network of verified local distributors, making it easier than ever to print, book and track letterbox campaigns across Australia.

What started as a teenager’s determination to build something from scratch has grown into a platform with more than 15,000 registered distributors and 2,500 businesses using the service.

We sat down with Seb to learn more about his journey, what drives him, and why Urban Collective has become home for Realrun.

Building from the ground up

For Seb, entrepreneurship has always been less about the industry and more about the challenge of building something meaningful.

“I’ve always loved systems and creating momentum,” he says. “Since I was a kid, I’ve been curious about building, growing and creating things.”

While still in high school, Seb knew he wanted to start a business – but with very little capital, his options were limited.

“The only thing I could really provide was my own labour,” he explains. “I started with a backpack and my own two legs, delivering letterbox advertising.”

Rather than seeing those limitations as setbacks, Seb used them as a foundation. As the business generated cash flow, he began building systems and processes that would eventually evolve into Realrun – a scalable technology platform bringing speed, transparency and reliability to an industry that had long been overlooked.

Why physical marketing still matters

At a time when AI and digital advertising dominate conversations, Realrun is taking a different approach.

“We believe physical marketing is becoming more premium,” Seb says. “People are constantly scrolling through content where every second or third post is an advertisement. It’s becoming harder to capture meaningful attention.”

Realrun aims to bridge the gap between traditional letterbox marketing and the convenience businesses have come to expect from digital platforms. Through the platform, businesses can organise, manage and track campaigns across Australia with greater simplicity and confidence.

The long-term vision? To make physical advertising as accessible and seamless as digital advertising.

Learning by doing

Starting a business at such a young age has meant learning every lesson firsthand.

“Every stage is something new,” Seb says. “Because I built my career through Realrun rather than following a traditional corporate path, I’ve had to learn quickly.”

One lesson has become central to his leadership style: don’t pretend to know everything.

“I’m confident about what I don’t know,” he explains. “When I identify a gap in my knowledge, I put my hand up and find someone who knows more than I do.”

Building a strong network of experienced mentors and specialists has been instrumental in helping both Seb and the business continue to grow.

The milestone that matters most

While many founders point to revenue or customer growth as defining moments, Seb’s proudest achievement is much simpler.

“Nothing excites me more than coming to work every day surrounded by a team of people who are all working towards the same mission.”

Having started the business entirely on his own, building a team of passionate people has become the most rewarding part of the journey.

“It was hard to imagine that in the early days. Walking into the office now and seeing everyone building together is definitely one of my proudest moments.”

Why Urban Collective?

When it came time to choose a headquarters, the decision was about more than just office space.

“I think it’s important for entrepreneurs to work in a quality environment,” Seb says.

“The place we come to every day should maximise our work culture and the overall experience of building the business.”

For Realrun, Urban Collective offered exactly that – with flexible workspaces, meeting rooms, a convenient location close to the city, and a community of ambitious business owners all under one roof.

Advice for aspiring founders

If Seb could leave future entrepreneurs with one piece of advice, it would be this: start with what genuinely excites you.

“The most important thing for me isn’t building the business that makes the maximum amount of money. My number-one priority is doing what I love.”

He believes passion is what gets people started, but it’s discipline, resilience and a willingness to keep learning that keep them moving forward.

“Think about what you love. For me, it was building systems. It didn’t necessarily matter which industry I entered.”

What’s next for Realrun?

The team is now focused on expanding Realrun across Australia, continuing to improve the technology behind the platform and growing its distributor network.

Their mission remains clear: to make letterbox advertising faster, easier and more reliable for businesses of every size – and ultimately become Australia’s leading letterbox advertising platform.

We’re proud to have founders like Seb and the Realrun team as part of the Urban Collective community. Watching ambitious businesses grow from an idea into a national platform is exactly what our community is all about.

Want to connect with Seb? You can follow his founder journey on Instagram and LinkedIn, or learn more about Realrun at realrun.com.au.