The gains have been made at the expense of Sinn Féin, who have slipped back two points this month to 17%
The Labour Party and Independents have gained in popularity according to the latest opinion poll - at the expense of Sinn Féin and other small parties.
Fianna Fáil remains marginally ahead of Fine Gael as the country's most popular party in the latest RED C poll for tomorrow's Sunday Business Post.
Fianna Fáil remains unchanged on 26% in this poll compared to a month ago, with Fine Gael also unchanged on 24%.
After a five point increase a month ago, Sinn Féin slip back two points this month to 17%.
Unaligned Independents gain 3 points to 13%, with the Independent Alliance unchanged on 3 - while Labour are up two to 6%.
The Greens are unchanged on 4%, while Solidarity/PBP drop two points to 4%.
The Social Democrats are unchanged on 3, while Renua drop a point to zero.
The poll was conducted between Monday and Friday this week.
This margin of error in the poll is just over 3%.