Allegra is a distinctive girls' name in England & Wales, ranking #990 in 2005 with 26 recorded births. The name reached its all-time peak in 2018 with 63 births ranking #641. Since 1996, the popularity has increased by 188.9%. In 2005, approximately 1 in every 11,087 girls born was named Allegra. STABLE Recent data shows the name is currently stable.