Isobelle is a moderately popular girls' name in England & Wales, ranking #279 in 2008 with 170 recorded births. The name reached its all-time peak in 2009 with 181 births ranking #265. Since 1996, the popularity has increased by 286.4%. In 2008, approximately 1 in every 1,857 girls born was named Isobelle. FALLING Recent data shows the name is currently falling.