Brennan is a distinctive boys' name in England & Wales, ranking #3450 in 2022 with 5 recorded births. The name reached its all-time peak in 2002 with 37 births ranking #559. Since 1996, the popularity has decreased by 75.0%. In 2022, approximately 1 in every 56,877 boys born was named Brennan. RISING Recent data shows the name is currently rising.