Alastair is a distinctive boys' name in United States, ranking #3665 in 2013 with 28 recorded births. The name reached its all-time peak in 2025 with 67 births ranking #2147. Since 1996, the popularity has increased by 64.7%. In 2013, approximately 1 in every 67,545 boys born was named Alastair. RISING Recent data shows the name is currently rising.