Declining since 1993, #3,848 for boys today.
Popularity of Dillan since 1975
Babies named Dillan per year in U.S. Social Security records.
Data table (by decade)
| Decade | Girls | Boys |
|---|---|---|
| 1970s | 0 | 10 |
| 1980s | 0 | 153 |
| 1990s | 31 | 2,643 |
| 2000s | 156 | 2,703 |
| 2010s | 139 | 1,205 |
| 2020s | 67 | 280 |
Meaning & origin
Dillan first appeared on U.S. baby name charts in 1975, riding on the coattails of the more popular Dillon spelling. Its peak year came in 1992, when it ranked highest in usage. Since then, its trajectory has been falling consistently from 1993 onward. In 2025, the name ranked 3848th, with approximately 1 in every 61,003 newborn boys receiving the name. Dillan is most commonly given in Texas, reflecting regional preference. The name's gradual decline mirrors broader trends away from similar-sounding names that were popular in the 1990s. As a variant of Dillon, it remains a recognizable but less common choice for parents seeking a modern-sounding name with Welsh roots.
Dillan is a spelling variant of Dillon, which itself derives from the Welsh surname Dylyn or Dyllon. The surname is believed to be of Irish origin, from the Gaelic name Diolún, meaning 'loyal' or 'faithful'. As a given name, Dillon gained popularity in the United States in the mid-20th century, and Dillan emerged as a less common alternative spelling.
Where Dillan is most popular
Births per 100,000 boys by state. Press play or drag the slider to watch it move across the decades. The lightest shade means too few recorded births.
Nicknames & variants
Nicknames: Dill, Dilly
Sibling names for Dillan
Names that share Dillan's style, for a brother or sister.
