His decision will see Richard Bridge, the company’s current creative director and other co-founder, take full ownership of the business for an undisclosed sum.
Terry’s future plans will see him stay within the leadership, creative and communication sectors, working in a senior consultant and board capacity.
Bridge said: "Nick has been at the heart of the company’s journey over the past 17 years. Together we have created an amazing company and brand - having a ball whilst doing it.
"Nick will be sorely missed but he leaves us in brilliant shape. As well as his central role over the past 17 years, he has been particularly instrumental in getting our business ready for its next phase, including the creation of a new super talented Banana Leadership Team (BLT) to take the business forward.
"I am excited about the future, the opportunities and growth we can expect, with new client growth in London and expansion of the team."
Terry added: "The last 17 years and the Top Banana journey has been epic - full of big ambition, enormous fun, and wonderful achievements. I’m incredibly proud of the business Richard and I have built, as well as the shape in which I leave it to enter into its next chapter of growth.
"My decision to step down, driven by both the desire to do other things, as well as let the next generation of Bananas drive the business forward, has not been an easy one. These guys are family, the energy support and passion they give is awe inspiring.
"However, I’m excited to see Top Banana move forward and thrive as well as enjoy some new professional challenges and experiences of my own."
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