Valentin Stalf was born in Vienna in 1985 and studied accounting and finance at the University of St. Gallen. He worked at Deutsche Bank and Roland Berger as a student, then joined Rocket Internet as an entrepreneur in residence.
In February 2013 he and Maximilian Tayenthal founded Papayer GmbH in Berlin, which sold a prepaid Mastercard for teenagers. The company raised a €2 million seed round in June 2014 and was renamed Number26. In 2016 it won a BaFin banking licence and became N26.
Funding grew fast. A $160 million Series C in March 2018 came from Tencent and Allianz X, and a $300 million Series D in January 2019 valued the bank at $2.7 billion. A $900 million Series E in October 2021 led by Third Point and Coatue valued it at $9 billion.
Regulators then set limits. BaFin fined N26 €4.25 million in 2021 and capped new customers at 50,000 a month, and N26 left the US in 2022. Stalf stepped down as CEO in 2025, and Mike Dargan took over in April 2026.