The UK Singles Chart is one of many music charts compiled by the Official Charts Company that calculates the best-selling singles of the week in the United Kingdom. Before 2004, the chart was only based on the sales of physical singles. This list shows singles that peaked in the Top 10 of the UK Singles Chart during 1999, as well as singles which peaked in 1998 and 2000 but were in the top 10 in 1999. The entry date is when the song appeared in the top 10 for the first time (week ending, as published by the Official Charts Company, which is six days after the chart is announced). Two hundred and three singles were in the top ten in 1999. Nine singles from 1998 remained in the top 10 for several weeks at the beginning of the year, while "Mr. Hankey, the Christmas Poo" by Mr. Hankey, "Say You'll Be Mine"/"Better the Devil You Know" by Steps and "Two in a Million"/"You're My Number One" by S Club 7 were all released in 1999 but did not reach their peak until 2000. "Chocolate Salty Balls (P.S. I Love You)" by Chef and Heartbeat"/"Tragedy" by Steps were the singles from 1998 to reach their peak in 1999. Forty-eight artists scored multiple entries in the top 10 in 1999. Christina Aguilera, Britney Spears, Eminem, Jennifer Lopez, S Club 7 and Westlife were among the many artists who achieved their first UK charting top 10 single in 1999. The first number-one single of the year was "Chocolate Salty Balls (P.S. I Love You)" by Chef, the South Park character voiced by Isaac Hayes. Overall, thirty-six different singles peaked at number-one in 1999, with Westlife (4) having the most singles hit that position. Background Multiple entries Two-hundred and three singles charted in the top 10 in 1999, with one-hundred and ninety-three singles reaching their peak this year. Forty-eight artists scored multiple entries in the top 10 in 1999. Steps had the most top 10 singles in 1999 with seven entries. Seven artists recorded four singles which reached the top 10 this year: Another Level, B*Witched, Melanie C, Ronan Keating, Vengaboys, Westlife and Will Smith. Britney Spears was one of nine artists with three top 10 entries, including the number-one single "...Baby One More Time". A1, Boyzone, Geri Halliwell, Honeyz, Lolly, Martine McCutcheon, S Club 7 and TQ were among the other artists