English place name, from heg, "hay", and leah, "clearing" — hay meadow. Unrelated to the comet, which is spelled Halley.
Hailey ranks 104th among American girls in 2025, with 2,561 born that year. Its best year was 2003, when 8,808 babies were given the name, ranking 26th. The typical living American called Hailey is about 20 years old today. It is relatively most common in Massachusetts, where it accounts for 0.18% of births.
Source: US Social Security Administration, national and state name files, 2025 release, and the Office for National Statistics for England and Wales. Etymology researched and written by our editors. Living-population and median-age figures are our own estimates, described in the methodology.