Survey conducted last year reported on here has some breakdown by religion - apparently it found 17 percent of Catholics want Northern Ireland to remain in the UK and "a majority of those who say they have no religion here support the union at 48 per cent, while 32 percent of those in the same category back a united Ireland"
And there's a quote from Dr Peter Shirlow, a social demographer and head of Liverpool University’s Institute of Irish Studies:
Observer, August 2021: https://www.theguardian.com/politics/20 ... ying-in-uk "Two-thirds of voters in Northern Ireland believe there should be a vote over its place in the UK, but only 37% want it to take place within the next five years ... Asked to state how they would vote, 49% said they would back remaining in the UK, while 42% backed being part of a united Ireland""There have been at least six household surveys now conducted since 2016 by the University of Liverpool, Queen’s University Belfast and the Ulster Unionist," he explained.
"All these surveys show majority support for remaining in the UK, a significant share of Catholics who support remaining in the UK and no growth in the very small share of Protestants who want Irish unification."
Politico has something on north and south polling: https://www.politico.eu/article/poll-ir ... ts-brexit/
Saturday’s results show 44 percent of people in Northern Ireland want to stay in the U.K., compared to 35 percent who want to leave.
In the south, support for unification is conditioned by who pays. Fifty-four percent of Irish Republic voters would reject unity if it hikes their tax bills, according to the survey, which was conducted by the polling firm Kantar.
Only one in eight would vote for unity if the handover required the Republic to take on Britain’s full costs of subsidizing Northern Ireland.