He supplemented his education with a diploma in small business management at the University of St. Gallen.

In 2004 he was elected as a member of the management board of the health insurance company Group Mutuel.

[2] Stahl's career in politics began as a member of Winterthur's municipal council between 1994 and 2001.

[2][3] In 2001, he missed the election to Winterthur's "Stadtrat" (city executive) by a single vote.

[4][5] In June 2018, he accepted a position with Schweizerischen Drogistenverband, the Swiss druggists association.