These are the Billboard Magazine number one albums of 1975, per the Billboard 200.
| Issue Date | Album | Artist(s) |
|---|---|---|
| January 4 | Elton John's Greatest Hits | Elton John |
| January 11 | ||
| January 18 | ||
| January 25 | ||
| February 1 | ||
| February 8 | Fire | Ohio Players |
| February 15 | Heart Like a Wheel | Linda Ronstadt |
| February 22 | AWB | Average White Band |
| March 1 | Blood on the Tracks | Bob Dylan |
| March 8 | ||
| March 15 | Have You Never Been Mellow | Olivia Newton-John |
| March 22 | Physical Graffiti | Led Zeppelin |
| March 29 | ||
| April 5 | ||
| April 12 | ||
| April 19 | ||
| April 26 | ||
| May 3 | Chicago VIII | Chicago |
| May 10 | ||
| May 17 | That's the Way of the World | Earth, Wind & Fire / Soundtrack |
| May 24 | ||
| May 31 | ||
| June 7 | Captain Fantastic and the Brown Dirt Cowboy | Elton John |
| June 14 | ||
| June 21 | ||
| June 28 | ||
| July 5 | ||
| July 12 | ||
| July 19 | Venus and Mars | Wings |
| July 26 | One of These Nights | Eagles |
| August 2 | ||
| August 9 | ||
| August 16 | ||
| August 23 | ||
| August 30 | Captain Fantastic and the Brown Dirt Cowboy | Elton John |
| September 6 | Red Octopus | Jefferson Starship |
| September 13 | The Heat Is On | The Isley Brothers |
| September 20 | Between the Lines | Janis Ian |
| September 27 | Red Octopus | Jefferson Starship |
| October 4 | Wish You Were Here | Pink Floyd |
| October 11 | ||
| October 18 | Windsong | John Denver |
| October 25 | ||
| November 1 | Red Octopus | Jefferson Starship |
| November 8 | Rock of the Westies | Elton John |
| November 15 | ||
| November 22 | ||
| November 29 | Red Octopus | Jefferson Starship |
| December 6 | Still Crazy After All These Years | Paul Simon |
| December 13 | Chicago IX - Chicago's Greatest Hits | Chicago |
| December 20 | ||
| December 27 |
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