What is a fiscal sponsor?

A fiscal sponsor is a nonprofit organization that provides fiduciary oversight, financial management, and other administrative services to help build the capacity of charitable projects. The role of the fiscal sponsor can include performing various administrative functions on behalf of the sponsored organization or program, including taking on the responsibility of receiving and administering charitable contributions on behalf of the sponsored organization.

Further reading:

https://www.councilofnonprofits.org/running-nonprofit/administration-and-financial-management/fiscal-sponsorship-nonprofits

https://boardsource.org/resources/fiscal-sponsorship/

https://nonprofitquarterly.org/fiscal-sponsorship-a-balanced-overview/