Boy name
Cillian
Cillian holds the #507 spot on the 2025 list of the most popular boy names in the U.S. That amounts to 595 newborn boys in a single year. The name is on the way up, moving from #957 in 2020 to #507 today. Its strongest year on record was 2024 (#463 nationally, 668 newborns), in a data series reaching back to 1995. The name's biggest fan base is in Alaska (#165 there in 2025).
Rankings
2025 rank
#507
among boy names
Trend
Rising
last 5 years
All-time peak
#463
in 2024 (2020s)
Babies in 2025
595
boys named Cillian
Cillian popularity, 1880–2025
Where Cillian is most popular
Share of boys born in 2025:lowhighno data (< 5 births)
Strongest states: Alaska (#165), Delaware (#203), Rhode Island (#200)
Uniqueness score
41/ 100Balanced
everywhereone of a kind
Well known, but far from crowded — the middle of the field. Based on how many babies per birth were named Cillian in the most recent year of SSA data.
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