Finn specialises in strategic comms for FMCG brands using consumer B2B, digital and corporate channels. Its clients include Quorn, Yorkshire Tea and Morphy Richards.
Sibbles will lead the agency’s digital, creative and content team and support the company’s drive for new business.
She worked for the online fashion retailer for four years, starting as features editor before rising to become its editor in March this year.
Before ASOS, Sibbles worked for The Guardian as deputy fashion editor and for Marie Claire as a commissioning editor.
Finn MD Richard Rawlins said: "Creative and content is at the heart of our commercial proposition, so Emma’s experience at ASOS will be invaluable in strengthening that proposition and providing more creative solutions for clients which meet their overall business objectives."