Isobelle is a moderately popular girls' name in England & Wales, ranking #322 in 2007 with 138 recorded births. The name reached its all-time peak in 2009 with 181 births ranking #265. Since 1996, the popularity has increased by 213.6%. In 2007, approximately 1 in every 2,218 girls born was named Isobelle. FALLING Recent data shows the name is currently falling.