The Monkeys chief executive Justin Mowday told the Herald that early account wins indicate that clients are looking for something different in their advertising partners.
The Meridian account was previously held by the Dentsu creative department in the local market.
The Monkeys was founded earlier this year when Mowday and his chief creative officer Damon Stapleton made a shock departure from advertising agency DDB.
The pair were recruited specifically to spearhead Accenture's move into the advertising space in the local market.
Mowday said that ASB and Meridian presented interesting creative challenges in their respective categories.
"Winning Meridian further fuels our mission to build the most interesting, diverse and talented team in New Zealand."
Mowday and Stapleton have been on a hiring spree in recent weeks as they look to build a team capable of managing these large accounts.
Mowday said it wouldn't be necessary to add many more than the 30 to 35 staff the company has already recruited to manage the ASB account.
He said that they hired in anticipation of further growth to come.
The emergence of the consulting firms in the advertising sector ramped up a notch in the last week, with the announcement that Deloitte had poached Colenso BBDO executives Ahmad Salim and Dan Wright to lead the local arm of their creative offing.
Deloitte Digital Creative has also started hiring staff to start building the business in New Zealand.