The 1999 IGA SuperThrift Tennis Classic was a women's tennis tournament played on indoor hard courts at The Greens Country Club in Oklahoma City, Oklahoma in the United States that was part of Tier III of the 1999 WTA Tour. It was the 14th edition of the tournament and was held from February 22 through February 28, 1999. First-seeded Venus Williams won her second consecutive singles title at the event and earned $27,000 first-prize money.[1][2] On the same day her sister Serena won the Open Gaz de France tournament, making them the first sisters to win WTA events in the same week.[3][4][5]