Tamsin is a distinctive girls' name in United States, ranking #17348 in 2000 with 5 recorded births. The name reached its all-time peak in 2017 with 27 births ranking #5033. Since 1996, the popularity has decreased by 28.6%. In 2000, approximately 1 in every 363,194 girls born was named Tamsin. FALLING Recent data shows the name is currently falling.