After graduating from Trinity College in Hartford he accepted a teaching position in the New York Institution for Deaf-mutes where he met and married Elizabeth Budd, who like Gallaudet's mother Sophia, was deaf.
Following in his father's footstepts, in 1852, Gallaudet established St. Ann’s Church for Deaf Mutes in New York City, and established the Gallaudet Home for Deaf-Mutes, near Poughkeepsie, in 1885.
One of Thomas Gallaudet's students, Henry Winter Syle, became the first deaf person to be ordained by the Episcopal Church.
Gallaudet is buried in Cedar Hill Cemetery in Hartford, Connecticut.