The two parties are both well ahead of Fianna Fáil.
Fine Gael has narrowly beaten out Sinn Féin in the latest opinion poll, edging ahead by just one point.
Leo Varadkar's party regained its lead over Mary Lou McDonald led Sinn Féin ahead of the Dublin Bay South by-election, according to the latest
Business Post/Red C poll.
Fine Gael is now up by one point to 30% on last month’s Red C poll, putting it just ahead of Sinn Féin which remains unchanged at 29%.
The two parties have been neck-and-neck in the polls for the past seven months, with Sinn Féin frequently coming out on top.
Both parties have managed to bridge a pretty significant lead against Taoiseach Micheál Martin's Fianna Fáil.
Last week,
The Sunday Times Behaviour and Attitudes Poll reported that Sinn Féin had taken a significant 10 point lead over Fine Gael, also eclipsing Fianna Fáil by 14 points.
The party, led by Mary Lou McDonald was up by four points to 34%, meanwhile, Tánaiste Leo Varadkar's party has dropped four points to 24% and Fianna Fáil is down two points to 20%.
The Green Party was also down one point to 4% and independent candidates went up a point to 9%.
