Iain is a distinctive boys' name in United States, ranking #3066 in 2018 with 38 recorded births. This places Iain in the top 22% of ranked US boys' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 2003 with 126 births ranking #1181. Since 1996, the popularity has decreased by 55.8%. In 2018, approximately 1 in every 47,776 boys born was named Iain. FALLING Recent data shows the name is currently falling.