Cosmo is a distinctive boys' name in England & Wales, ranking #856 in 2019 with 35 recorded births. This places Cosmo in the top 14% of ranked UK boys' names for the year. Its actual usage is classified as Uncommon. The name reached its all-time peak in 2025 with 57 births ranking #639. Since 1996, the popularity has increased by 600.0%. In 2019, approximately 1 in every 8,682 boys born was named Cosmo. STABLE Recent data shows the name is currently stable.