Brennan is a distinctive boys' name in United States, ranking #1023 in 2023 with 213 recorded births. The name reached its all-time peak in 2009 with 1,464 births ranking #242. Since 1996, the popularity has decreased by 76.2%. In 2023, approximately 1 in every 8,021 boys born was named Brennan. STABLE Recent data shows the name is currently stable.