Willem is a distinctive boys' name in United States, ranking #1811 in 1997 with 53 recorded births. The name reached its all-time peak in 2003 with 122 births ranking #1208. Since 1996, the popularity has increased by 15.2%. In 1997, approximately 1 in every 35,568 boys born was named Willem. STABLE Recent data shows the name is currently stable.