Extended definition
APC (Article Processing Charge) is the fee charged by gold or hybrid OA journals to process and publish an accepted article. It is the dominant financial mechanism sustaining gold OA among commercial publishers (Elsevier, Springer Nature, Wiley, Taylor & Francis, MDPI, Frontiers). Solomon and Björk (2012) offered the first systematic analysis of the APC market, showing wide price dispersion. The current range goes from about US 12,000 (Nature, Science, Cell, and other top venues — in some cases via “transformative agreements”). APCs are typically paid by: the author (out of pocket), the institution (via central fund), the funding agency (FAPESP covers APC with justification; NIH/ERC cover routinely), or via waiver/discount (negotiated case by case, especially for authors from low-income countries via Hinari/Research4Life). Transformative agreements (read-and-publish) between institutions and publishers consolidate bulk institutional payment instead of article-by-article transactions.
When it applies
APC is required whenever an author chooses gold OA in a journal that adopts the model. It is a central element of research financial planning in fields where gold OA is the effective norm (health, biomedical sciences) and must enter funding proposals from the start. In hybrid OA, APC is optional article by article — the author can publish behind a paywall without paying APC or pay APC to make it OA. In fields where diamond OA is viable (humanities, some Latin American social sciences), APC can be avoided entirely. Checking the funder’s policy on APC coverage is standard practice before submission.
When it does not apply
It does not apply in diamond OA (no APC for either author or reader) — the dominant model in SciELO, Redalyc, AmeliCA, and many European society journals. It does not apply in green OA via preprint/postprint deposit in institutional repositories. It does not apply in pure subscription journals without OA option. Researchers without funding and in institutions with limited budgets can seek waivers or prioritize diamond/green; paying APC out of pocket for a top international Q1 publication can reach a significant fraction of monthly salary — a non-trivial financial decision.
Applications by field
— Health and biomedical sciences: high APC is the norm; PLOS Biology, eLife, Nature Communications charge US 1,500-3,000 in top journals; diamond OA more frequent in Latin America and continental Europe. — MDPI/Frontiers: APC in US$ 2,000-3,000, scale production model; controversy over editorial quality (some journals in these groups were downgraded in SCImago/JIF).
Common pitfalls
The first pitfall is not budgeting APC into the project from the start — having an accepted manuscript without funds to pay APC blocks publication. The second is confusing high fees with high quality — APC reflects in part the publisher’s market power and operational cost, not editorial rigor. The third is ignoring institutional agreements: many universities have read-and-publish arrangements that cover APC for their researchers at selected publishers — using this discount is obvious but frequently neglected. The fourth is confusing APC with submission fees (some journals charge a submission fee regardless of outcome — rare in modern models). The fifth is assuming APC is always paid before publication: some journals charge only after acceptance, avoiding financial pressure during review.