Founded in 1995, Zen offers a wide range of internet services to businesses and consumers, with more than 100,000 customers and annual revenues of £71 million in 2018.
Red was awarded the brief following a competitive pitch process led by Zen’s CEO Paul Stobart and founder and chairman Richard Tang.
Red managing director of technology Jenny Fieldgate will lead the account.
Zen aims to double revenue in the next five years, and Red’s brief is to raise brand awareness amongst consumer and business audiences and help drive new customer sign-ups.
"Zen has ambitious plans for growth in the coming years and want a partner to help us raise our profile and reach new customers," Stobart said.
"We felt that Red’s consumer and B2B expertise was the right fit for us and we’re excited about what we can achieve together."
Fieldgate added: "Zen has a great, and as yet largely untold story to tell in a market that is ripe for disruption. Its approach makes it stand out from competitors and we’re incredibly excited to get the chance to play a part in helping it to achieve its business goals over the coming years."
Headquartered in Rochdale, Zen has been recognised as PC Pro’s Best Internet Service Provider for 15 years running and picked up several other IT industry awards for customer service.
The company made this year’s Sunday Times 100 Best Companies to Work For list.