# List of Billboard Hot 100 number ones of 2009

The Billboard Hot 100 is a chart that ranks the best-performing singles of the United States. Published by Billboard magazine, the data are compiled by Nielsen SoundScan based collectively on each single's weekly physical and digital sales, and airplay. There were a total of 12 number-one singles in 2009, although 13 claimed the top spot as Beyoncé's "Single Ladies (Put a Ring on It)" reached its peak position in 2008, and thus is excluded.
In 2009, six acts achieved their first U.S. number-one single either as a lead artist or a featured guest: Lady Gaga, Colby O'Donis The Black Eyed Peas, Jay Sean, Jason Derulo, and Owl City. Jay-Z earned his first number-one single as a lead artist (with Alicia Keys) with "Empire State of Mind", after being the featured guest on three number-one singles. Lady Gaga and Black Eyed Peas each earned two number-one singles.
Black Eyed Peas broke the record for having spent the most consecutive weeks at number one (26 weeks consecutive weeks at the top) with "I Gotta Feeling" the longest-running number-one single of 2009 and of the 2000s (decade) (fourteen weeks), along with the non-consecutive Mariah Carey's "We Belong Together" in 2005, and their first number-one single "Boom Boom Pow", which topped the chart for twelve weeks.
Notable highlights of the 2009 Billboard Hot 100 issues include Kelly Clarkson's "My Life Would Suck Without You", which broke the record for the biggest leap to number one by jumping from number 97 to the number-one position. Britney Spears's "3" became the only non-'American Idol' song to debut at number one in the 2000s (decade).

## Chart history

Key :
| † | Indicates best-performing single of 2009 |
| No. | Issue date | Song | Artist(s) |
| re | January 3 | "Single Ladies (Put a Ring on It)" | Beyoncé |
| re | January 10 | "Single Ladies (Put a Ring on It)" | Beyoncé |
| 968 | January 17 | "Just Dance" | Lady Gaga featuring Colby O'Donis |
| 968 | January 24 | "Just Dance" | Lady Gaga featuring Colby O'Donis |
| 968 | January 31 | "Just Dance" | Lady Gaga featuring Colby O'Donis |
| 969 | February 7 | "My Life Would Suck Without You" | Kelly Clarkson |
| 969 | February 14 | "My Life Would Suck Without You" | Kelly Clarkson |
| 970 | February 21 | "Crack a Bottle" | Eminem, Dr. Dre and 50 Cent |
| 971 | February 28 | "Right Round" | Flo Rida |
| 971 | March 7 | "Right Round" | Flo Rida |
| 971 | March 14 | "Right Round" | Flo Rida |
| 971 | March 21 | "Right Round" | Flo Rida |
| 971 | March 28 | "Right Round" | Flo Rida |
| 971 | April 4 | "Right Round" | Flo Rida |
| 972 | April 11 | "Poker Face" | Lady Gaga |
| 973 | April 18 | "Boom Boom Pow"† | The Black Eyed Peas |
| 973 | April 25 | "Boom Boom Pow"† | The Black Eyed Peas |
| 973 | May 2 | "Boom Boom Pow"† | The Black Eyed Peas |
| 973 | May 9 | "Boom Boom Pow"† | The Black Eyed Peas |
| 973 | May 16 | "Boom Boom Pow"† | The Black Eyed Peas |
| 973 | May 23 | "Boom Boom Pow"† | The Black Eyed Peas |
| 973 | May 30 | "Boom Boom Pow"† | The Black Eyed Peas |
| 973 | June 6 | "Boom Boom Pow"† | The Black Eyed Peas |
| 973 | June 13 | "Boom Boom Pow"† | The Black Eyed Peas |
| 973 | June 20 | "Boom Boom Pow"† | The Black Eyed Peas |
| 973 | June 27 | "Boom Boom Pow"† | The Black Eyed Peas |
| 973 | July 4 | "Boom Boom Pow"† | The Black Eyed Peas |
| 974 | July 11 | "I Gotta Feeling" | The Black Eyed Peas |
| 974 | July 18 | "I Gotta Feeling" | The Black Eyed Peas |
| 974 | July 25 | "I Gotta Feeling" | The Black Eyed Peas |
| 974 | August 1 | "I Gotta Feeling" | The Black Eyed Peas |
| 974 | August 8 | "I Gotta Feeling" | The Black Eyed Peas |
| 974 | August 15 | "I Gotta Feeling" | The Black Eyed Peas |
| 974 | August 22 | "I Gotta Feeling" | The Black Eyed Peas |
| 974 | August 29 | "I Gotta Feeling" | The Black Eyed Peas |
| 974 | September 5 | "I Gotta Feeling" | The Black Eyed Peas |
| 974 | September 12 | "I Gotta Feeling" | The Black Eyed Peas |
| 974 | September 19 | "I Gotta Feeling" | The Black Eyed Peas |
| 974 | September 26 | "I Gotta Feeling" | The Black Eyed Peas |
| 974 | October 3 | "I Gotta Feeling" | The Black Eyed Peas |
| 974 | October 10 | "I Gotta Feeling" | The Black Eyed Peas |
| 975 | October 17 | "Down" | Jay Sean featuring Lil Wayne |
| 976 | October 24 | "3" | Britney Spears |
| re | October 31 | "Down" | Jay Sean featuring Lil Wayne |
| 977 | November 7 | "Fireflies" | Owl City |
| 978 | November 14 | "Whatcha Say" | Jason Derulo |
| re | November 21 | "Fireflies" | Owl City |
| 979 | November 28 | "Empire State of Mind" | Jay-Z and Alicia Keys |
| 979 | December 5 | "Empire State of Mind" | Jay-Z and Alicia Keys |
| 979 | December 12 | "Empire State of Mind" | Jay-Z and Alicia Keys |
| 979 | December 19 | "Empire State of Mind" | Jay-Z and Alicia Keys |
| 979 | December 26 | "Empire State of Mind" | Jay-Z and Alicia Keys |

## Number-one artists

List of number-one artists by total weeks at number one :
| Position | Artist | Weeks at No. 1 |
| 1 | The Black Eyed Peas | 26 |
| 2 | Flo Rida | 6 |
| 3 | Jay-Z | 5 |
| 3 | Alicia Keys | 5 |
| 5 | Lady Gaga | 4 |
| 6 | Colby O'Donis | 3 |
| 7 | Beyoncé | 2 |
| 7 | Kelly Clarkson | 2 |
| 7 | Jay Sean | 2 |
| 7 | Lil Wayne | 2 |
| 7 | Owl City | 2 |
| 12 | Eminem | 1 |
| 12 | Dr. Dre | 1 |
| 12 | 50 Cent | 1 |
| 12 | Britney Spears | 1 |
| 12 | Jason Derulo | 1 |