The North would vote more strongly to remain in the EU if there was another Brexit poll, a study suggested.
A total of 69% would favour Remain if there was another referendum compared to 56% at the two years ago, the UK in a Changing Europe project said.
Catholics were much more likely to support a united Ireland if there was a “hard exit” in which the UK left the customs union and single market.
The border is one of the most vexed questions facing negotiators who aim to strike a deal by the autumn ahead of the UK’s withdrawal from the EU next year.
Brendan O’Leary, Lauder professor of political science at the University of Pennsylvania, who also holds a visiting position at Queen’s University Belfast, said: “Our results show that if there was another referendum, people in Northern Ireland would vote more strongly to remain in the EU.
“The proportion wanting to Remain has risen since the 2016 referendum as more people have become aware of the possible costs and inconveniences of leaving the EU, as citizens and as employees or employers.”
The survey was carried out for the Economic and Social Research Council which is funding the UK in a Changing Europe project.
It said it provided an authoritative, non-partisan, and impartial reference point for those seeking information, insights, and analysis about UK-EU relations that stands aside from politics surrounding the debate.
Findings from the survey included:
Principal investigator John Garry, professor of political behaviour at QUB, said: “We find Catholics and Protestants most prefer the option that would avoid the need for any new barriers on borders, either in the Irish Sea or across Ireland, They want the UK as a whole to stay in the customs union and single market.”