The job losses have particularly affected Paddy Power’s marketing team, in what one source described as a "clearout".
The merger resulted in the departure of then Paddy Power chief marketing officer Gav Thompson.
Campaign understands that a number of Paddy Power’s marketing team who had joined during Thompson’s tenure have either left or are in the process of leaving.
Thompson was replaced by his counterpart at Betfair, Jonathan Devitt, who took on a joint chief marketing officer role in March.
Ken Robertson, who was promoted to advertising director in April, remains in place.
A spokesman for Paddy Power Betfair, when asked about the job losses, simply said: "I’m afraid there’s no one here left to comment."