Stefan Nillessen

Stefan Nillessen (born 2 January 2003) is a Dutch middle-distance runner. In 2024, he became Dutch national champion over 1500 metres.

Career
He was selected for the 1500 metres at the 2022 World Athletics U20 Championships in Cali, Colombia.

He won gold in the 1500 metres at the 2023 European Athletics U23 Championships in Espoo.

He is one of a group of athletes coached by Tomasz Lewandowski. He signed a sponsorship deal with Nike in 2024. He ran a personal best of 3:34.32 for the 1500 metres in Turku, Finland on 18 June 2024.

He won the Dutch national title over 1500m in Hengelo in June 2024.

Personal life
He is from Groesbeek near Nijmegen.