Born in Sieradz, Poland, Stępiński started his career playing for youth sides Piast Błaszki and Pogoń-Ekolog Zduńska Wola.

In 2011, he signed for Ekstraklasa club Widzew Łódź, going on to make 33 appearances and scoring five goals over two seasons.

[5] On 6 August 2021, he was loaned to Cypriot side Aris Limassol with an option to buy at the end of the season.

In the 2024 January transfer window, Stępinski moved to Omonia for an undisclosed fee.

He made his first senior appearance on 2 February 2013 in an international friendly against Romania.