Mary Lou McDonald’s party is up four points to 34pc, while Tánaiste Leo Varadkar has dropped four points to 24pc.
Meanwhile, Fianna Fáil is down two points to 20pc and the Green Party are down one point to 4pc.
The poll was taken as the Government announced property tax increases for hundreds of thousands of homeowners while also unveiling plans to phase out the Pandemic Unemployment Payment (PUP) from September.
Sinn Féin has said it will abolish property tax and said the PUP should be phased out “naturally” when people return to work.
The Sunday Times/Behaviour and Attitudes poll has the Social Democrats up two to 4pc, Labour are down one to 3pc and Aontú is up one to 1pc and People Before Profit are unchanged at 1pc.
Independent candidates are up a point to 9pc.
The survey also found one-in-five voters or 750,000 people are still undecided about how they will vote in general election.
The poll consisted of a survey of 909 Irish voters who were questioned at their homes between May 27 and June 8.