Connolly will leave the post after serving three terms, and he will be leading the campaign to fill the role within the coming months.
Obvious contenders for the position include David Sproul, Martin Eadon and Vince Niblett, who are managing directors at Deloitte and sit on the firm’s executive committee.
A spokesperson from Deloitte would not confirm that the three were in the running for the post and said that it was too early to rule anyone in out.
It is understood that Niblett was initially thought of as the preferred candidate but is unlikely to take on the role after he was recently promoted to head of audit practices.
Within the coming months Deloitte’s board will begin to sound out the candidates to take over the post that saw Connolly awarded a £5.2m salary last year – making him the City’s best paid accountant.
During his post, Connolly also brought Deloitte’s partner profits to £883,000, while income climbed to almost £2bn during 2009.
Connolly is not expected to leave Deloitte and will look to assume another role within the firm.
The news comes as the accountancy firm has made a number of recent acquisitions, including UK based real estate group Drivers Jonas and most recently Swiss management consultancy group Exsigno.