Isobelle is a moderately popular girls' name in England & Wales, ranking #375 in 2002 with 91 recorded births. The name reached its all-time peak in 2009 with 181 births ranking #265. Since 1996, the popularity has increased by 106.8%. In 2002, approximately 1 in every 2,938 girls born was named Isobelle. FALLING Recent data shows the name is currently falling.