The 2003 Davidoff Swiss Indoors was a men's tennis tournament played on indoor carpet courts at the St. Jakobshalle in Basel in Switzerland and was part of the International Series of the 2003 ATP Tour. The tournament ran from October 20 through October 26, 2003. Guillermo Coria won the singles title.
Guillermo Coria defeated David Nalbandian by Walkover
- It was Coria's 5th title of the year and the 6th of his career.
Mark Knowles / Daniel Nestor defeated Lucas Arnold / Mariano Hood 6–4, 6–2
- It was Knowles' 6th title of the year and the 30th of his career. It was Nestor's 6th title of the year and the 32nd of his career.