Over the past 110 years, 2 337 girls and 379 916 boys have been named Billy. The name Billy ranks 2639th in the United States among the most common names for girls. For the first time more than ten times newborns were named Billy in 1915. The peak of popularity of the name Billy came in the 1920s and 1930s. You can see absolute numbers and relative numbers on the chart. Indicators per 100K more accurately assess the popularity of the name.