The number of Catholic baptisms across Ireland has fallen by almost 30% over the past decade, according to a new report.
A briefing from The Iona Institute, using figures supplied by almost every Catholic diocese in Ireland, found baptisms had fallen by 29.6% compared with ten years earlier.
The Christian organisation said declining birth rates were responsible for much of the reduction, alongside an increase in the number of people identifying as having no religion.
Births across Ireland fell by 18.8% over the same period, leading the institute to estimate that around 60% of the decline in baptisms could be explained by fewer children being born.
Some dioceses experienced much larger falls than others.
In Dublin, baptisms dropped from 15,759 in 2015 to 9,465 in 2025, a fall of almost 40%. Meath recorded a 40.8% decline, while Down and Connor, which includes Belfast, saw a fall of 37.9%.
However, baptisms in Achonry fell by just 3.2%, while Elphin recorded a small increase of 0.9%.
The report also highlighted changes in the religious identity of young children.
In the Republic of Ireland, 78.3% of children aged under five were recorded as Roman Catholic in the 2016 Census. By 2022, that had fallen to 65.4%.
Over the same period, the proportion of children in that age group recorded as having no religion increased from 9.2% to 15.6%.
Despite the changes, The Iona Institute said the figures suggested most parents who identified as Catholic were still choosing baptism for their children.
Dr Tom Finegan, chairman of The Iona Institute, said: "Given that births have fallen by almost a fifth in the last ten years, and more people are ticking the 'No Religion' box in the Census, we could expect nothing but a big drop in baptism figures."
He said the figures also demonstrated the continuing influence of what the institute described as "cultural Catholicism", with families continuing to choose sacraments such as baptism, First Holy Communion and Confirmation despite declining levels of regular church attendance.
Dr Finegan added: "The fall in baptisms must be seen not simply as the result of secularisation, but even more as a result of falling births."
The institute said Ireland's baptism figures reflected two significant trends, fewer children being born and a growing proportion of families identifying as having no religion.
