Jack has once again topped the list of names registered with the Central Statistics Office for baby boys in 2020, a position it has held every year but one since 2007.
However, Grace has knocked Emily off the top of the list for girls, a place it had held since 2011.
Last year, it was pushed back to number three behind Grace and Fiadh and was followed by Sophie and Ava.
Of registrations for boys in 2020, the top five most popular names were Jack, James, Noah, Daniel and Conor.
CSO Statistician Carol Anne Hennessy said that for the third consecutive year the list distinguishes names registered that contain the síneadh fada and other diacritics.
According to the CSO, back in 1970, John, Michael, Patrick, David and James were the names most favoured by parents of newborn baby boys.
There were 193 newborns named John in 2020, but just over 7.3% of the number of boys given the name John (2,629) in 1970.
However, not one of the top five names for girls in 2020 appeared in the top 100 names a half century earlier.
Mary, Catherine, Margaret, Ann and Sharon were the most popular names for baby daughters in 1970, with 1,896 baby girls named Mary in that year.
In 2020, there were 410 baby girls named Grace, 21.6% of the number of girls given the name Mary (1,896) in 1970.
Sonny was the only new entrant into the top 100 for boys in 2020.
The boys' names with most growth in popularity in terms of rank between 2019 and 2020 were Rian, jumping 33 places from 119th to 86th, and Eoghan, which moved 29 places from 108th to 79th.
There were seven new entrants to the top 100 for girls: Penny, Luna, Cora, Fíadh (with a síneadh fada), Croía, Elsie and Paige.
Croía has grown most in popularity, rising from 162nd place in 2019 to 95th in 2020, a jump of 67 places. Cora jumped in popularity from 127th in 2019 to 90th in 2020, a rise in 37 places.
Some less popular names for boys included Orion, Creed, Romeo, Klay and Séadna. Less popular girls' names included Zaria, Vienna, Fódhla, Marlee and Roxie.