Cillian
- Gender
- Boy
- Say it
- KIL-ee-an
- Origin
- Irish
- UK rank, 2025
- #162 for boys
- US rank, 2025
- #507 for boys
Big in Northern Ireland
Cillian is a boys' name of Irish origin. In 2025 it ranked 162nd for boys in the UK (376 babies) and 507th for boys in the US (595 babies).
What does Cillian mean?
Irish: Irish Cillian or Cillín, perhaps from ceall, church
St Cillian (Kilian) was a 7th-century Irish missionary martyred at Würzburg in Germany.
Is Cillian a girl's or a boy's name?
Cillian is a boys' name. In 2025, it was given to 376 boys in the UK and 595 boys in the US. Too few girls were given it to be listed.
How popular is Cillian in the UK?
- Rank in 2025
- #162among boys
- Babies in 2025
- 376about 1 in 800 boys
- Five-year trend
- Steadyup 24% in five years
- Same name in a class
- 1.7%chance among 15 boys
In 2025, 376 boys in the UK were named Cillian, making it the 162nd most popular name for boys. Five years earlier, in 2020, it was 173rd. Its busiest year was 2024, with 489 boys.
Half of all the boys named Cillian in the UK since 1996 were born between 2015 and 2023, the years shaded on the chart below.
In 2025, 538 boys in the UK were given Cillian or a name that sounds the same. With every name's spellings counted this way, that ranks #119, up from #162 for this spelling alone.
Among boys in 2025, it was 217th in England and Wales, 100th in Scotland and 11th in Northern Ireland.
Cillian in the UK, year by year
| Year | Boys | Rank |
|---|---|---|
| 2025 | 376 | #162 |
| 2024 | 489 | #122 |
| 2023 | 422 | #144 |
| 2022 | 384 | #155 |
| 2021 | 329 | #187 |
| 2020 | 347 | #173 |
| 2019 | 338 | #174 |
| 2018 | 355 | #174 |
| 2017 | 285 | #216 |
| 2016 | 218 | #271 |
| 2015 | 213 | #269 |
| 2014 | 144 | #350 |
| 2013 | 119 | #388 |
| 2012 | 108 | #421 |
| 2011 | 101 | #432 |
| 2010 | 99 | #432 |
| 2009 | 85 | #479 |
| 2008 | 64 | #578 |
| 2007 | 78 | #485 |
| 2006 | 47 | #666 |
| 2005 | 29 | #866 |
| 2004 | 15 | #1,301 |
| 2003 | 15 | #1,205 |
| 2002 | 9 | #1,594 |
| 2001 | 12 | #1,283 |
| 2000 | 13 | #1,165 |
| 1999 | 8 | #1,582 |
| 1998 | 12 | #1,180 |
| 1997 | 12 | #1,174 |
| 1996 | 12 | #1,146 |
How popular is Cillian in the US?
- Rank in 2025
- #507among boys
- Babies in 2025
- 595about 1 in 2,900 boys
- Five-year trend
- Rising fastup 187% in five years
- Same name in a class
- under 1%chance among 15 boys
In 2025, 595 boys in the US were named Cillian, making it the 507th most popular name for boys. Five years earlier, in 2020, it was 957th. Its busiest year was 2024, with 668 boys. It first appears in the records in 1995.
Half of all the boys named Cillian in the US since 1880 were born between 2017 and 2024, the years shaded on the chart below.
In 2025, 2,017 boys in the US were given Cillian or a name that sounds the same. With every name's spellings counted this way, that ranks #200, up from #507 for this spelling alone.
Cillian in the US, year by year
| Year | Boys | Rank |
|---|---|---|
| 2025 | 595 | #507 |
| 2024 | 668 | #463 |
| 2023 | 477 | #594 |
| 2022 | 353 | #735 |
| 2021 | 341 | #747 |
| 2020 | 228 | #957 |
| 2019 | 186 | #1,078 |
| 2018 | 193 | #1,052 |
| 2017 | 170 | #1,126 |
| 2016 | 177 | #1,105 |
| 2015 | 121 | #1,416 |
| 2014 | 87 | #1,730 |
| 2013 | 77 | #1,850 |
| 2012 | 73 | #1,941 |
| 2011 | 66 | #2,034 |
| 2010 | 54 | #2,353 |
| 2009 | 52 | #2,450 |
| 2008 | 51 | #2,466 |
| 2007 | 39 | #2,972 |
| 2006 | 42 | #2,743 |
| 2005 | 10 | #7,089 |
| 2004 | 8 | #8,137 |
| 2003 | 0 | – |
| 2002 | 0 | – |
| 2001 | 6 | #9,236 |
| 2000 | 0 | – |
| 1999 | 5 | #9,905 |
| 1998 | 0 | – |
| 1997 | 0 | – |
| 1996 | 0 | – |
| 1995 | 5 | #8,861 |
Names like Cillian
Names given in the same years and the same naming tradition, with a similar sound.
Finn Ronan Cassian Rowan Kian Callan Kayden Lochlan Aiden Brody Flynn Caelan
Other spellings of Cillian
Names related to Cillian
More Irish names
Oscar Rory Maeve Ryan Nolan Quinn Orla Cody Erin Connor Declan Casey Kennedy Lennon Kevin Sloane
Sources
Figures from Baby names in England and Wales (Office for National Statistics), Babies' first names (National Records of Scotland), Baby names (Northern Ireland Statistics and Research Agency) and Popular Baby Names (US Social Security Administration). Nameling last updated them on 20 October 2026. How the figures are worked out, and the data to download.
To cite this page: Nameling, “Cillian: name meaning, origin and popularity”, https://www.nameling.co.uk/names/cillian, updated 20 October 2026.