Killian is a distinctive boys' name in England & Wales, ranking #627 in 2025 with 59 recorded births. This places Killian in the top 10% of ranked UK boys' names for the year. Its actual usage is classified as Uncommon. The name reached its all-time peak in 2022 with 79 births ranking #492. Since 1996, the popularity has increased by 490.0%. In 2025, approximately 1 in every 4,609 boys born was named Killian. FALLING Recent data shows the name is currently falling.
Killian is a modern-feeling Irish-rooted name that is often connected with the same family as Cillian. It has a strong sound and a smoother international look than some more obviously Gaelic spellings.
The name became more visible through anglicised use and modern chart popularity, especially outside Ireland. It keeps a Celtic identity while feeling very accessible.