Billy has been given to about 389,665 people in the United States since 1880. It was most common in 1934, which makes it a interwar name.
Its best year was 1934, when 9,659 babies were given the name, ranking 20th. The typical living American called Billy is about 69 years old today. It is relatively most common in Mississippi, where it accounts for 0.04% 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.