Sian is a popular girls' name in England & Wales, ranking #99 in 1999 with 524 recorded births. The name reached its all-time peak in 1997 with 760 births ranking #72. Since 1996, the popularity has decreased by 28.3%. In 1999, approximately 1 in every 538 girls born was named Sian. FALLING Recent data shows the name is currently falling.