Alastair is a distinctive boys' name in United States, ranking #3026 in 2006 with 36 recorded births. The name reached its all-time peak in 2025 with 67 births ranking #2147. Since 1996, the popularity has increased by 111.8%. In 2006, approximately 1 in every 57,087 boys born was named Alastair. RISING Recent data shows the name is currently rising.