Slater's move is one of a series of internal promotions by the agency designed to drive continued growth across its global network.
Simon White, the managing director of Momentum London, and Allan Cobb, shopper marketing director of Momentum Worldwide, have been promoted to joint managing directors of Momentum UK, overseeing the London and Manchester offices.
Additionally, Kevin McNulty, current CMO of Momentum Worldwide has expanded his remit to become regional director of Europe.
Slater will be heavily involved with the creative direction for some of Momentum's most important clients, while also supporting its ambitious business development programme.
Most recently, Slater's projects have included several films for Hudson Whiskey and Balvenie (William Grant & Sons), national activations for Coca-Cola, American Express and Powerade, as well as packaging design for Stoli Chocolate Raspberry.
Chris Weil, chairman and CEO of Momentum Worldwide said: "This is a significant appointment, as it signals a focused effort to leverage the strengths of our Manchester and London agencies into a combined UK offering"