In Belfast, members of the public could not attend the event at City Hall and there was an overall limit on the number of people allowed to gather.
A short ceremony, led by Lord Mayor Frank McCoubrey, was live-streamed online.
In Enniskillen, Taoiseach (Irish Prime Minister) Micheál Martin represented the Irish government at a Remembrance Sunday service in St Macartin’s Cathedral.
He also laid a wreath at the town’s war memorial alongside First Minister Arlene Foster.
In 1987, 12 people were killed by an IRA bomb during the town’s Remembrance ceremony.
Speaking at the event, Mrs Foster said Mr Martin had been “very keen to come here today to continue that tradition that has now been set up”.
She added: “He is very welcome here in Enniskillen as we mark what is a very important day, right across Northern Ireland, but of course here in Enniskillen, it has a particular resonance.”
Mr Martin said it was a privilege to be able to show “solidarity with all of the people in Enniskillen and beyond”.
In Enniskillen, Taoiseach (Irish Prime Minister) Micheál Martin represented the Irish government at a Remembrance Sunday service in St Macartin’s Cathedral.