Miller will take up the reins in September after Meantime founder and brewmaster Alastair Hook decided the company required an experienced marketeer to take it to the next phase of its development.
Talking to OLN, he said the aspiration was to grow its production to 100,000 hl from its current 25,000 hl in the next five years.
Hook said: "We have been at the forefront of the British craft brewing movement for 10 years, specialising in unpasturised, brewer-conditioned beers of exceptional taste and flavour.
"The super premium lager category is very competitive and it’s mostly world beers.
"I came to the conclusion that we needed to get some sales and marketing experience into the business. Nick’s appointment marks a considerable change (to our) approach.
"There is no point brewing great beer if you don’t have the distribution and marketing in place to get your message to the consumer.”
Miller joined Miller Brands UK, a subsidiary of SAB Miller, in October 2005 as the new company’s first sales director. He was appointed managing director in October 2008.
He said: “I am sad to be leaving a great company and team but also very excited by my new challenge with Meantime.
"I have hugely enjoyed my time at Miller Brands and am very proud of the team’s success to date. I am sure that the strong team I leave behind will continue to lead the organisation to even greater heights.”