| Date | Artist - Title | Weeks at #1 |
|---|---|---|
1999 Number One Songs | ||
| – | Chef - Chocolate Salty Balls | 1 |
| – | Steps - Heartbeat / Tragedy | 1 |
| – | Fatboy Slim - Praise You | 1 |
| – | 911 - A Little Bit More | 1 |
| – | Offspring - Pretty Fly (For A White Guy) | 1 |
| – | Armand Van Helden feat. Duane Haeden - You Don't Know Me | 1 |
| – | Blondie - Maria | 1 |
| – | Lenny Kravitz - Fly Away | 1 |
| – | Britney Spears - Baby One More Time | 2 |
| – | Boyzone - When The Going Gets Tough | 2 |
| – | B*Witched - Blame It On The Weatherman | 1 |
| – | Mr Oizo - Flat Beat | 2 |
| – | Martine McCutcheon - Perfect Moment | 2 |
| – | Westlife - Swear It Again | 2 |
| – | Backstreet Boys - I Want It That Way | 1 |
| – | Boyzone - You Needed Me | 1 |
| – | Shanks and Bigfoot - Sweet Like Chocolate | 2 |
| – | Baz Luhrmann - Everybody's Free (To Wear Sunscreen) | 1 |
| – | S Club 7 - Bring It All Back | 1 |
| – | Vengaboys - Boom Boom Boom Boom!! | 1 |
| – | ATB - 9PM (Till I Come) | 2 |
| – | Ricky Martin - Livin' La Vida Loca | 3 |
| – | Ronan Keating - When You Say Nothing At All | 2 |
| – | Westlife - If I Let You Go | 1 |
| – | Geri Halliwell - Mi Chico Latino | 1 |
| – | Lou Bega - Mambo No 5 | 2 |
| – | Vengaboys - We're Going To Ibiza | 1 |
| – | Eiffel 65 - Blue (Da Ba Dee) | 3 |
| – | Christina Aguilera - Genie In A Bottle | 2 |
| – | Westlife - Flying Without Wings | 1 |
| – | Five - Keep On Movin' | 1 |
| – | Geri Halliwell - Lift Me Up | 1 |
| – | Robbie Williams - She's The One / It's Only Us | 1 |
| – | Wamdue Project - King Of My Castle | 1 |
| – | Cliff Richard - Millennium Prayer | 3 |
| – | Westlife - I Have A Dream / Seasons In The Sun | 4 |
36 different songs hit number one in the UK during 1999.
