Allegra is a distinctive girls' name in England & Wales, ranking #804 in 2008 with 42 recorded births. The name reached its all-time peak in 2018 with 63 births ranking #641. Since 1996, the popularity has increased by 366.7%. In 2008, approximately 1 in every 7,518 girls born was named Allegra. STABLE Recent data shows the name is currently stable.