"A Red Letter Day" is a single by British electronic music group Pet Shop Boys. It was released as the fourth single from their 1996 album Bilingual on 17 March 1997. The single peaked at high #9 on the UK Singles Chart, making it another top 10 single for the group. However it then fell straight out of the UK top 40 (to #42) the following week. At the time, this was a record as the biggest such fall to ever occur in UK chart history, but it was then beaten five months later by Embrace with their single "My Weakness is None of Your Business" (which fell from #9 to #44 the following week).
The duo were admirers of the sound of Motiv8, who had remixed various other artists at the time. Neil Tennant asked the man behind Motiv8 (Steve Rodway) to remix this single, even visiting Rodway at work in his studio during the remix. After it was finished and delivered, Tennant insisted that a synth line, which Rodway had come up with on the Motiv8 version, should be used on the Pet Shop Boys' own main mix. After unsuccessful attempts to recreate Rodway's riff, it eventually had to be sampled from the Motiv8 mix. Thus, as well as appearing on the Motiv8 remix, it appears on the Pet Shop Boys' main version.