"Lonely Days" is a ballad by the Bee Gees. Written by Barry, Robin and Maurice Gibb, and featured on their album 2 Years On, in the US it reached #3, their highest chart up to that point. Atco released it a few weeks ahead because the Bee Gees were touring the US. The record success helped establish the band as expert pop stylists. It was their first Top Five hit in the US, peaking at number three in the Billboard Hot 100 and reaching number one in the Cashbox and Record World charts.
On Friday, 21 August 1970, the three Gibb brothers announced they would reunite and start recording together nearly 16 months after Robin quit the group. They said later that they wrote "Lonely Days" and "How Can You Mend a Broken Heart" at their first reunion session, but the exact day when they recorded the song is unknown, however, a tape of stereo mixes received at Atlantic in October bears the tantalizing notation 'August 20, 1970' which if true means the brothers announced the reunion the day after it happened.
This song was sung by all three together to Maurice's piano and bass and Bill Shepherd's string and horn arrangement, the slow verses contrasting with the pounding chorus. The song incorporated the innovative structure and knack for changing tempos exemplified by the second side of The Beatles' Abbey Road album, released the previous year and a clear influence on this single. "Lonely Days" shifts back and forth between a piano-and-strings-dominated verse reminiscent of "You Never Give Me Your Money" and "Golden Slumbers," and an up-tempo stomping chorus that echoes "Carry That Weight"; perhaps as an acknowledgment of the debt, as the record approaches its fade-out, the lead singer's voice is filtered to sound like John Lennon's.
The song starts with a piano, when the singer sings the first line, the orchestra was started to play. At 1:12, the drums with handclaps was heard as the song became a little faster, the horns were heard as a response to the lines, Lonely days and Lonely nights. Near the end of the song, Barry was heard singing lead vocals with Robin and Maurice singing background vocals.