Bill Charlap was born in New York City into a musical family. His father, Moose Charlap, was a Broadway composer and songwriter whose credits included the scores to Peter Pan, The Conquering Hero, Whoop-up, Alice Through the Looking Glass and Kelly.
His mother, Sandy Stewart, is a popular song singer who performed with Benny Goodman, co-starred on TV's Perry Como Show and scored a Grammy nomination for her hit single, My Coloring Book by the songwriting team of Kander and Ebb. Mr. Charlap began playing the piano at a very young age. He studied with jazz pianist Jack Reilly and classical pianist Eleanor Hancock and informally picked up pointers from jazz/popular song pianist Dick Hyman, who was a distant cousin on his father's side.