"Did I Let You Know" is a song from the Red Hot Chili Peppers' 2011 album I'm with You and was released as the album's fourth single in January 2012 as a radio-only single exclusively in Brazil.On December 13, 2011, the band released a statement on their Brazilian website saying due to the song getting heavy radio airplay in Brazil and the song winning a poll voted on by the fans they decided to make it the next single there. This is the first single chosen by the fans.