Allegra is a distinctive girls' name in England & Wales, ranking #963 in 2007 with 31 recorded births. The name reached its all-time peak in 2018 with 63 births ranking #641. Since 1996, the popularity has increased by 244.4%. In 2007, approximately 1 in every 9,875 girls born was named Allegra. STABLE Recent data shows the name is currently stable.