Garreth is a distinctive boys' name in United States, ranking #7295 in 2005 with 10 recorded births. This places Garreth in the bottom 45% of ranked US boys' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 1998 with 18 births ranking #3900. In 2005, approximately 1 in every 199,715 boys born was named Garreth. FALLING Recent data shows the name is currently falling.