Sian is a moderately popular girls' name in England & Wales, ranking #361 in 2010 with 125 recorded births. The name reached its all-time peak in 1997 with 760 births ranking #72. Since 1996, the popularity has decreased by 82.9%. In 2010, approximately 1 in every 2,568 girls born was named Sian. FALLING Recent data shows the name is currently falling.