The first same-sex religious marriages can be arranged in Northern Ireland from Tuesday.
There are, however, exemptions and protections for religious bodies that do not wish to conduct same-sex marriages.
Same-sex marriage has been legally recognised in NI since January but did not extend to ceremonies in churches or to religious bodies.
A consultation on extending that provision to religious same-sex marriages was opened by the Northern Ireland Office (NIO) and the new regulations are based on its results.
The UK government said religious bodies cannot be “compelled by any means” to carry out services.
Couples can give their 28 days’ notice of intent to have a religious service from Tuesday 1 September, which means the first ceremonies could take place on 29 September.
‘Protections’ in place’
The legislation contains equality law protections so that religious bodies and officiants cannot be held to be unlawfully discriminating against same-sex couples if they refuse to marry them.
That protection has also been extended to cover church halls and other buildings owned by a church.
Same-sex marriage campaigners have welcomed the move, but are now urging the government to make marriage fully equal by allowing same-sex couples with an existing civil partnership to be able to convert their partnership into a marriage.
Patrick Corrigan, Amnesty International’s Northern Ireland director, said it was up to the government to “finish the job”.
“This is an important issue for many couples in Northern Ireland, who have previously been prevented by law from marrying in their own church,” he said.
“We now urge the government to finish the job of marriage equality in Northern Ireland without further delay, by allowing couples in civil partnerships to convert to married status if they so wish.”
Mr Corrigan welcomed the fact the new law will protect religious freedom and that churches will not be “compelled nor prevented” from offering same-sex ceremonies.