He will work across the range of Heresy's clients, which include Nestle, Texaco, Madame Tussaud's, Speedo and Hoseasons holidays.
Bayfield was one of the founding partners of Arkwright, which he set up three years ago with the art director Jim Bolton.
The consultancy ditched its advertising work when Bolton rejoined HHCL & Partners at the end of last year.
Bayfield joins Heresy later this month on a full-time contract, but will be allowed to take time out to work on Arkwright screenwriting and book projects. He becomes the first major creative hiring since Chime aligned all its advertising and marketing operations under the Heresy name.
Shaun McIlrath, the Heresy executive creative director, who previously worked with Bayfield at HHCL, said the hiring was in line with his aim of amassing a team of "creative grown-ups".
"We encourage creatives to work directly with clients but, to do that, we need people who can talk to them on a broad range of issues," he said.
"Chas isn't only a broad thinker but a fantastic practitioner of advertising."
Bayfield, whose creative credits also include the AA and the "I fancy your mum" work for Birds Eye Ready Meals, said: "Heresy's creative department is still small enough for me to have a genuine effect on the agency's output."