Gillermo is a distinctive boys' name in United States, ranking #6706 in 2002 with 10 recorded births. The name reached its all-time peak in 1998 with 21 births ranking #3534. Since 1996, the popularity has decreased by 23.1%. In 2002, approximately 1 in every 194,147 boys born was named Gillermo. FALLING Recent data shows the name is currently falling.