Isobelle is a moderately popular girls' name in England & Wales, ranking #489 in 1997 with 57 recorded births. The name reached its all-time peak in 2009 with 181 births ranking #265. Since 1996, the popularity has increased by 29.5%. In 1997, approximately 1 in every 5,144 girls born was named Isobelle. FALLING Recent data shows the name is currently falling.