The deal has been structured as an earnout for an undisclosed cash payment with future payments based on PainePR’s performance over the next four years.
PainePR has a gross income of around $9m (£5m) and around 50 employees.
The acquisition follows the firm’s takeover of UK operation Band & Brown Communications last month and brings the number of PR agencies in Cossette’s portfolio to three. Band & Brown and PainePR are to work in collaboration with Cossette’s other PR firm Optimum Public Relations.
Cossette counts Duracell and JP Morgan Chase among its clients.