The Billboard Hot 100 is a chart that ranks the best singles of the United States. Published by Billboard magazine, the data are compiled by Nielsen SoundScan based collectively on each single's weekly physical sales and airplays. The longest running number-one single is "Smooth" by Santana featuring Rob Thomas, which attained 12 weeks at number-one. Ten of those weeks were logged in 1999 and two additional weeks were logged in 2000.
| Issue Date | Song | Artist(s) | Reference |
|---|---|---|---|
| January 2 | "I'm Your Angel" | R. Kelly and Céline Dion | |
| January 9 | |||
| January 16 | "Have You Ever?" | Brandy | |
| January 23 | |||
| January 30 | "...Baby One More Time" | Britney Spears | [1] |
| February 6 | [2] | ||
| February 13 | "Angel of Mine" | Monica | |
| February 20 | |||
| February 27 | |||
| March 6 | |||
| March 13 | "Believe" | Cher | |
| March 20 | |||
| March 27 | |||
| April 3 | |||
| April 10 | "No Scrubs" | TLC | |
| April 17 | |||
| April 24 | |||
| May 1 | |||
| May 8 | "Livin' la Vida Loca" | Ricky Martin | |
| May 15 | |||
| May 22 | |||
| May 29 | |||
| June 5 | |||
| June 12 | "If You Had My Love" | Jennifer Lopez | |
| June 19 | |||
| June 26 | |||
| July 3 | |||
| July 10 | |||
| July 17 | "Bills, Bills, Bills" | Destiny's Child | |
| July 24 | "Wild Wild West" | Will Smith featuring Dru Hill and Kool Moe Dee | |
| July 31 | "Genie in a Bottle" | Christina Aguilera | |
| August 7 | |||
| August 14 | |||
| August 21 | |||
| August 28 | [3] | ||
| September 4 | "Bailamos" | Enrique Iglesias | |
| September 11 | |||
| September 18 | "Unpretty" | TLC | |
| September 25 | |||
| October 2 | |||
| October 9 | "Heartbreaker" | Mariah Carey featuring Jay-Z | [4] |
| October 16 | |||
| October 23 | "Smooth" | Santana featuring Rob Thomas | |
| October 30 | |||
| November 6 | |||
| November 13 | |||
| November 20 | |||
| November 27 | |||
| December 4 | |||
| December 11 | |||
| December 18 | |||
| December 25 |
|
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