This study analyses and profiles public ancillary funds (PubAFs), charitable trusts that act as intermediaries between public donors and approved nonprofit beneficiary organisations. PubAFs are an important part of Australia's philanthropic landscape given their public benefit purpose, yet little is known about this sector's characteristics and identities. This paper examines PubAFs, analysing online databases and reports and PubAF websites (where available). Based on the analysis of data from three sources: the Australian Charities and Not‐for‐profits Commission, Australian Taxation Office, and websites of 991 PubAFs (where available), this study provides valuable insights for the public, philanthropic practitioners, and researchers. Findings systematically map the field to develop an extended taxonomy, as a basis for promoting understanding and legitimacy beyond PubAFs’ moral intentions, providing valuable insights into an opaque group of organisations at a time when the philanthropic sector's transparency is limited and legitimacy is being questioned.