Jack and Katie were the favourite baby names for parents in Northern Ireland, the Statistics and Research Agency has revealed.
More than 3,000 names were used for children
They were also the most popular names in 2004 and Jack has now been the most popular boys' name for three years.
Matthew was the boy's runner up and Emma was in second spot for girls.
Only one of the 1975 top 10 boys' names (James) is still in the top 10. None of the top 10 girls' names from 1975 appear in the 2005 top 10 list.
There were more than 330 baby boys named Jack and more than 280 baby girls named Katie registered in 2005.
In 1975 the most popular boys' and girls' names in the province were David and Joanne.
GIRLS TOP TEN
The SRA said that over the last decade, parents have become more diverse in the names they have given to their babies.
In 2005, there were approximately 1,800 girls' and 1,200 boys' names used, compared with 1,500 girls' and 1,000 boys' names in 2001.
Looking at the 20 most popular boys' first names in 2005, Jake and Lewis have entered the top 20 and steadily increased in popularity over the last three years. Patrick and David are no longer in the top 20 most popular boys' names.
Further down the list and Noah has risen from 108 to 57 and Harvey has risen from 117 in 2004 to rank 76 in 2005.
BOYS TOP TEN
Boy's names with decreased popularity include Aodhan, down 49 places over the past year to 139 and Louis, down 42 places to 126.
There have also been a number of rises in the popularity of some girl's names over the year, with Isabella rising from 200 to rank 79 in 2005 and Ruby rising from 155 to rank 55.
Rebecca is the only new name in the top 20 for 2005, replacing Emily.
Decreases in popularity for girls' names include Kathryn, which has fallen from rank 70 to rank 156 and Katherine has fallen by 74 places to rank 164.