August is the most popular wedding month for the fourth year running
New figures from the Central Statistics Office (CSO) show 91 same-sex marriages took place in Ireland between November and December last year.
The data is the first available since Ireland passed the same-sex marriage referendum.
The numbers also show the average age of grooms in 2015 was 35.3 years, slightly more than the average in 2014.
In the past 50 years, the average age of grooms has fallen from 29.4 - in 1965 - to a low of 26.2 in 1977.
A similar trend is seen for brides, with the average age falling from 26 in 1965 to 24 in 1977.
This has increased to a high of 33.2 in 2015.
This means that last year, the groom was older than bride in just over 63% of marriages.
The number of marriages registered last year was 22,025 - which equates to an unadjusted marriage rate of 4.8 per 1,000 population.
This is just 20 marriages less than in 2014, when 22,045 marriages took place.
In 2015, 88.1% of marriages were also the first marriage for both the groom and bride.
And for the fourth consecutive year, August was the most popular month for marriage.
Religious ceremonies accounted for the highest proportion of marriages, at 66.3%.
There were 12,486 (56.7%) Catholic marriage ceremonies, 393 (1.8%) Church of Ireland, 73 (0.3%) Presbyterian ceremonies - while The Spiritualist Union of Ireland performed 822 (3.7%) marriage ceremonies.
The remaining 831 (3.8%) of couples opted for other religious ceremonies.
While the most recent divorce data available, from 2014, shows there were 2,629 divorces granted by the Circuit Court and High Court.
This was a decrease of 320 on the 2013 figure.