The first name Cillian
A boy’s name.
2 syllables Male
Popularity
Babies registered in England and Wales, 1996–2025
In 2025, 230 boys were named Cillian, making it the 217th most popular boys’ name. It peaked in 2024, with 285 births (#177).
Office for National Statistics; years with fewer than three births are not published and show as zero. Compare Cillian with other names.
Popularity in the United States
Babies named Cillian at birth, 1880–2025
In 2025, 595 boys born in the United States were named Cillian, the 507th most popular boys’ name that year. It was used most in 2024, when 668 were.
US Social Security Administration, from applications for a Social Security card. A name is only published for a year when at least five babies were given it, so quieter years show as zero.
Questions
- How popular is the name Cillian?
- In 2025, 230 boys born in England and Wales were named Cillian, ranking 217th. Its peak was 2024, with 285 births.
- Is Cillian a boy's or a girl's name?
- Mostly a boy's name: 100% of the 4,090 US babies named Cillian since 1880 were boys.
- When was Cillian most popular?
- 2024 in the United States, when 668 babies were named Cillian, its highest rank at 463rd.