Willem is a distinctive boys' name in United States, ranking #1573 in 1998 with 68 recorded births. The name reached its all-time peak in 2003 with 122 births ranking #1208. Since 1996, the popularity has increased by 47.8%. In 1998, approximately 1 in every 28,108 boys born was named Willem. STABLE Recent data shows the name is currently stable.