This lists songs that hit number one on the charts in the US during 1975. If a song spent nonconsecutive weeks at number one, the number of weeks for each occurrence at the top is shown in parenthesis.
| Date | Artist - Title | Weeks at #1 |
| December 29 1974 – January 11 1975 | Elton John - Lucy In The Sky With Diamonds | 2 |
| January 12 – 18 1975 | Barry Manilow - Mandy | 1 |
| January 19 – 25 1975 | Carpenters - Please Mr. Postman | 1 |
| January 26 – February 1 1975 | Neil Sedaka - Laughter In The Rain | 1 |
| February 2 – 8 1975 | Ohio Players - Fire | 1 |
| February 9 – 15 1975 | Linda Ronstadt - You're No Good | 1 |
| February 16 – 22 1975 | Average White Band - Pick Up The Pieces | 1 |
| February 23 – March 1 1975 | Eagles - Best Of My Love | 1 |
| March 2 – 8 1975 | Olivia Newton-John - Have You Never Been Mellow | 1 |
| March 9 – 15 1975 | Doobie Brothers - Black Water | 1 |
| March 16 – 22 1975 | Frankie Valli - My Eyes Adored You | 1 |
| March 23 – 29 1975 | Labelle - Lady Marmalade | 1 |
| March 30 – April 5 1975 | Minnie Riperton - Lovin' You | 1 |
| April 6 – 19 1975 | Elton John - Philadelphia Freedom | 2 |
| April 20 – 26 1975 | B.J. Thomas - (Hey Won't You Play) Another Somebody Done Somebody Wrong Song | 1 |
| April 27 – May 17 1975 | Tony Orlando and Dawn - He Don't Love You (Like I Love You) | 3 |
| May 18 – 24 1975 | Earth, Wind and Fire - Shining Star | 1 |
| May 25 – 31 1975 | Freddy Fender - Before The Next Teardrop Falls | 1 |
| June 1 – 7 1975 | John Denver - Thank God I'm A Country Boy | 1 |
| June 8 – 14 1975 | America - Sister Golden Hair | 1 |
| June 15 – July 12 1975 | Captain and Tennille - Love Will Keep Us Together | 4 |
| July 13 – 19 1975 | Paul McCartney - Listen to What the Man Said | 1 |
| July 20 – 26 1975 | Van McCoy - The Hustle | 1 |
| July 27 – August 2 1975 | Eagles - One Of These Nights | 1 |
| August 3 – 16 1975 | Bee Gees - Jive Talkin' | 2 |
| August 17 – 23 1975 | Hamilton, Joe Frank and Reynolds - Fallin' In Love | 1 |
| August 24 – 30 1975 | KC and the Sunshine Band - Get Down Tonight | 1 |
| August 31 – September 13 1975 | Glen Campbell - Rhinestone Cowboy | 2 |
| September 14 – 20 1975 | David Bowie - Fame | 2 (1) |
| September 21 – 27 1975 | John Denver - I'm Sorry/Calypso | 1 |
| September 28 – October 4 1975 | David Bowie - Fame | 2 (1) |
| October 5 – 25 1975 | Neil Sedaka - Bad Blood | 3 |
| October 26 – November 15 1975 | Elton John - Island Girl | 3 |
| November 16 – 22 1975 | KC and the Sunshine Band - That's The Way (I Like It) | 2 (1) |
| November 23 – December 13 1975 | Silver Convention - Fly Robin Fly | 3 |
| December 14 – 20 1975 | KC and the Sunshine Band - That's The Way (I Like It) | 2 (1) |
| December 21 – 27 1975 | Staple Singers - Let's Do It Again | 1 |
| December 28 1975 – January 3 1976 | Bay City Rollers - Saturday Night | 1 |
36 different songs hit number one in the US during 1975.
Top 5 Songs of 1975
1: Captain and Tennille - Love Will Keep Us Together
2: Glen Campbell - Rhinestone Cowboy
3: Elton John - Philadelphia Freedom
4: Freddy Fender - Before The Next Teardrop Falls
5: Frankie Valli - My Eyes Adored You
2: Glen Campbell - Rhinestone Cowboy
3: Elton John - Philadelphia Freedom
4: Freddy Fender - Before The Next Teardrop Falls
5: Frankie Valli - My Eyes Adored You