Alastair is a distinctive boys' name in United States, ranking #2600 in 2015 with 47 recorded births. The name reached its all-time peak in 2025 with 67 births ranking #2147. Since 1996, the popularity has increased by 176.5%. In 2015, approximately 1 in every 40,771 boys born was named Alastair. RISING Recent data shows the name is currently rising.