The 1999 SEAT Open was a women's tennis tournament played on indoor carpet courts in Kockelscheuer, Luxembourg which was part of Tier III of the 1999 WTA Tour.

[1] It was the fourth edition of the tournament and was held from 20 September until 26 September 1999.

Qualifier Kim Clijsters won the singles title and earned $27,000 first-prize money.

The following players received wildcards into the singles main draw: The following players received wildcards into the doubles main draw: The following players received entry from the singles qualifying draw: The following players received entry as lucky losers: Kim Clijsters defeated Dominique Van Roost, 6–2, 6–2 Irina Spîrlea / Caroline Vis defeated Tina Križan / Katarina Srebotnik, 6–1, 6–2