Did your publication come about with a grant from a research fund? Make sure that you always include the cost of Open Access publishing in the project budget.
You can consult the Open Policy Finder database to find out about your fund's Open Access policy. For specific journals, you can find out how to meet the research fund's Open Access requirements using the Journal Checker Tool (developed by cOAlition-S).
Plan-S: the guidelines and requirements for Open Access
In 2021, a consortium of research funds adopted a policy (Plan-S) that sets out the requirements for Open Access. The main requirements state that scholarly output must be made Open Access immediately under an open (Creative Commons) licence and with copyright retained. Examples of research funders that follow Plan-S guidelines include NWO and Horizon.