Legislation coming into effect today enables couples in a civil partnership or marriage registered here to convert a same sex civil partnership to a marriage or an opposite sex marriage into a civil partnership.
There are more than 1,300 same-sex civil partnerships in the North of Ireland.
Finance Minister Conor Murphy said: “Today is an important milestone in the campaign for marriage equality.
“There are over 1,300 same sex civil partnerships here. Seventeen couples are expected to convert their civil partnerships to marriages today with a total of 32 planned for this week. ”
The minister offered his congratulations to all the couples converting today.
“As a gesture of support I have waived the conversion fee for those couples and for all couples who wish to convert their civil partnership to a marriage for a full year.”
He added: “I would like to congratulate those couples who are converting their partnerships today and wish them a very happy life together.”
Matrimonial lawyer Clare Lenaghan said the development meant that Northern Ireland is “finally catching up with its neighbours”.
Same sex marriage law was debated and voted on five times by the Northern Ireland Assembly between 2012 and 2015 without progress.
“There has been significant yet long overdue progress in the area of same sex marriage in Northern Ireland within the last 12 months,” Ms Lenaghan said.
According to the lawyer, the North of Ireland had long been seen as out of step both with the rest of the UK – where same sex marriage had been introduced in 2014 – and with the Republic of Ireland, where it had been brought about in 2015.
“This upcoming regulatory change will see Northern Ireland finally catching up with its neighbours across the rest of the UK and the Republic of Ireland in relation to marriage equality – this is undoubtedly a welcome and hugely important change,” Ms Lenaghan added.