Billy is a moderately popular boys' name in England & Wales, ranking #110 in 2025 with 481 recorded births. The name reached its all-time peak in 2005 with 955 births ranking #71. Since 1996, the popularity has decreased by 47.4%. In 2025, approximately 1 in every 565 boys born was named Billy. STABLE Recent data shows the name is currently stable.
Billy is the familiar short form of William and carries the inherited meaning usually given as "resolute protector". It feels open, friendly, and much less formal than the full traditional version.
Billy has long been used as both a nickname and a stand-alone given name. It remains especially familiar in Britain and the United States through its mix of informality and tradition.