It was Henry's biggest
U.S. hit, reaching No. 4 in early 1961. The
B-side on the
single release was "Just My Baby and Me". On its initial release in December 1960, the U.S. release on the
Argo record label was titled "I Don't Know Why". However, about ten weeks later, Argo announced that due to confusion arising from the song being mistaken for the 1931 song called "
I Don't Know Why (I Just Do)", they changed the name of this song to "But I Do". The
UK release on the
Pye label and the Australian release on the
Coronet label were both titled "But I Do". The UK version spent 19 weeks in the charts and peaked at No. 3 in the first week of May 1961. The song was made popular again after its use in a 1993 UK television commercial for the
Fiat Cinquecento, appearances in the 1994 film
Forrest Gump, the 1999 film
Mickey Blue Eyes, and a 2019 commercial for
Expedia and its ability to provide dog-friendly hotel accommodations.
Chart history Weekly charts Year-end charts ==Bobby Vinton cover==