Tamsin is a distinctive girls' name in England & Wales, ranking #655 in 2010 with 57 recorded births. The name reached its all-time peak in 1996 with 137 births ranking #271. Since 1996, the popularity has decreased by 58.4%. In 2010, approximately 1 in every 5,632 girls born was named Tamsin. FALLING Recent data shows the name is currently falling.