On 10 March 2017 (his 19th Birthday he signed a three-and-a-half-year professional contract and joined their first team during their 2016–17 season under head coach Urs Fischer.
[4] Schmid started their 2017–18 season with Basel's first team and had three league appearances in the early stages, but the only game where he played the full 90 minutes was the 2017–18 Swiss Cup match against amateur club FC Wettswil-Bonstetten.
[8] He quickly became an integral part of the club and was instrumental in helping the record champion achieve promotion back to the Swiss Super League.
[10] On 16 April 2023, he played his 100th game for Grasshoppers,[11] a 1–3 home loss to FC Sion, where he sadly had to be substituted at half time due to a head injury.
[13] He quickly reestablished himself as a leading figure in a struggling Basel side and started nearly every game of the 2023–24 season, while also scoring two goals and supplying six assists.
On 16 March 2023, he received his first call up to the Switzerland national football team in preparation for their upcoming UEFA Euro qualifying campaign.