Reilly is a distinctive boys' name in United States, ranking #1224 in 2011 with 143 recorded births. This places Reilly in the top 9% of ranked US boys' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 2007 with 218 births ranking #911. In 2011, approximately 1 in every 13,280 boys born was named Reilly. FALLING Recent data shows the name is currently falling.