Milly is a distinctive girls' name in United States, ranking #3785 in 2005 with 39 recorded births. The name reached its all-time peak in 2014 with 129 births ranking #1657. Since 1996, the popularity has increased by 254.5%. In 2005, approximately 1 in every 47,377 girls born was named Milly. STABLE Recent data shows the name is currently stable.