Alastair is a distinctive boys' name in United States, ranking #2187 in 2017 with 61 recorded births. The name reached its all-time peak in 2025 with 67 births ranking #2147. Since 1996, the popularity has increased by 258.8%. In 2017, approximately 1 in every 30,333 boys born was named Alastair. RISING Recent data shows the name is currently rising.