Some Open Access journals are financed through cost participation of the authors. These so-called Article Processing Charges (APC) are intended to secure the operations of the non-free journal and its profit revenue for commercial publishers, instead of the proceeds from subscriptions. The APCs are often between 1,000 and 3,000 euros per article. Also for the publication of books in Open Access, the costs are normally charged to the author, the so-called BPCs (book processing charges).

Some journals waive these costs on request or for certain author groups, for example within the framework of the DEAL project. DEAL is an initiative of the Alliance of German Science Organisations that negotiates so-called transformative agreements (also known as "Publish and Read" agreements) with major commercial publishers on behalf of German research institutions. Transformative agreements bundle reading access with the right of affiliated researchers to publish Open Access. This means you may be able to publish in a hybrid or Open Access journal without paying an APC yourself. Whether a specific journal is covered depends on your institution's individual agreements. Check with your library or your institution's Open Access office to find out which journals you can publish in at no personal cost.

In third-party projects, you can apply for publication funds to finance Open Access costs. Furthermore, many university and research organisations offer institutional publication funds. You can find an international overview of OA publication funds in the Open Access Directory. The network Radical Open Access offers a further overview of “Funding and publication opportunities for Open Access books”.