Is Cillian a boy or girl name?
Cillian is a boy name in the US. In 2024, 6 girls and 668 boys were named Cillian, so 0.9% were girls. Across 1880–2024, 0.2% of the 3,492 US babies named Cillian were girls.
- Boy rank, 2024
- #463
- Girl rank, 2024
- #13,797
- Babies named Cillian since 1995
- 3,492
- Most popular year
- 2024
- 674 babies
Boys and girls named Cillian, by decade
Every year
| Year | Boys | Boy rank | Girls | Girl rank |
|---|---|---|---|---|
| 2024 | 668 | #463 | 6 | #13,797 |
| 2023 | 476 | #594 | 0 | – |
| 2022 | 352 | #737 | 0 | – |
| 2021 | 340 | #749 | 0 | – |
| 2020 | 228 | #957 | 0 | – |
| 2019 | 186 | #1,077 | 0 | – |
| 2018 | 193 | #1,051 | 0 | – |
| 2017 | 170 | #1,126 | 0 | – |
| 2016 | 177 | #1,107 | 0 | – |
| 2015 | 121 | #1,418 | 0 | – |
| 2014 | 87 | #1,733 | 0 | – |
| 2013 | 77 | #1,853 | 0 | – |
| 2012 | 73 | #1,946 | 0 | – |
| 2011 | 66 | #2,040 | 0 | – |
| 2010 | 54 | #2,358 | 0 | – |
| 2009 | 52 | #2,458 | 0 | – |
| 2008 | 51 | #2,477 | 0 | – |
| 2007 | 39 | #2,982 | 0 | – |
| 2006 | 42 | #2,750 | 0 | – |
| 2005 | 10 | #7,206 | 0 | – |
| 2004 | 8 | #8,267 | 0 | – |
| 2003 | 0 | – | 0 | – |
| 2002 | 0 | – | 0 | – |
| 2001 | 6 | #9,466 | 0 | – |
| 2000 | 0 | – | 0 | – |
| 1999 | 5 | #10,182 | 0 | – |
| 1998 | 0 | – | 0 | – |
| 1997 | 0 | – | 0 | – |
| 1996 | 0 | – | 0 | – |
| 1995 | 5 | #9,094 | 0 | – |
Highest rank
As a boy name, Cillian reached #463 in 2024. As a girl name, it reached #13,797 in 2024. Ranks count every name SSA published for that year and sex, so they go well past the top 1,000.
Names from the same era
These names were also most popular in the 2020s, with a similar number of babies. They can work as sibling or middle names that feel like they belong together.
Names spelled like Cillian
Source: US Social Security Administration baby name data, 1880–2024. Counts are Social Security card applications for US births; SSA leaves out names given to fewer than 5 babies in a year. Updated 2026-10-05. How these numbers are made.