Royce has left to spend more time working on Kindeo, the app he co-founded that enables people to record their memories in one place.
A connection with Freuds is set to remain, with the agency now handling PR for Kindeo.
Royce arrived at Freuds from video tech company Rockabox, which he joined in 2013. Before this he spent almost 13 years at Isobar, the Dentsu-owned digital agency.
Royce’s clients at Freuds included Diageo, PepsiCo, Nike, Mars, Compare The Market and Asda.
Freuds CEO Andrew McGuinness said: "With the increasing success of his app, Kindeo, Seb has decided to focus more of his attention on the development of that business. I am delighted to say that Freuds will be continuing to work with him by handling Kindeo’s PR going forward."