Museum Willet-Holthuysen is part of the Stichting Amsterdam Museum (Amsterdam Museum Foundation). The Amsterdam Museum receives a fixed amount of funding from the City of Amsterdam for managing and maintaining the city's collection and the historical buildings. It also receives annual funding from the BankGiro Loterij.
The BankGiro Loterij is the Netherlands culture lottery. Almost 600,000 Dutch people play this lottery. They can win prizes while supporting various forms of culture in the Netherlands: from windmills to concerts and from festivals to museums. Thanks to these players, the BankGiro Loterij is able to contribute to 70 leading institutions that help to promote culture in the Netherlands. The BankGiro Loterij has supported Museum Willet-Holthuysen since 2006.