Civil ceremonies made up 29.5% of the 20,680 marriages in 2013, according to figures released by the CSO today.
The number of Roman Catholic ceremonies was down from 13,497 in 2012 to 12,921 last year, with the number of civil ceremonies up from 5,797 to 6,096.
The 'Statistical Yearbook of Ireland' published this morning paints a picture of Ireland under categories such as people, society, business and the economy.
It also shows there were 68,930 births registered in 2013 - representing a decrease of 3,295 on figures from 2012.
Almost 37% of the births recorded were to mothers aged between 30-34 while, the most popular baby names in 2013 were Jack and Emily.
Findings from some of the other categories show the number of people in employment increased to 1.87 million in 2013.
Ttoday's statistics also show Irish people enjoy holidaying - Irish residents made almost 6.6 million trips out of the country last year, 85% of which were to other EU countries.