Examples
Worked examples
- Is an instance
A journal achieves its S2O renewal threshold and opens the year's volume to all readers.
- Is an instance
Library consortium members renew the journal in solidarity to support its diamond-equivalent OA model.
Counter-examples
Looks similar, but isn't
- Not an instance
Marketing a journal as S2O but charging an APC if the threshold is missed.
- Not an instance
Withdrawing institutional support, free-riding on other libraries' renewals.
Editorial commentary
Subscribe-to-Open (S2O) was developed by Annual Reviews and Berghahn Books and has been adopted by EDP Sciences, IWA Publishing and others. Each year, the publisher sets a renewal threshold; if reached, the entire content of that volume is published open access. If the threshold is missed, the volume reverts to closed access. The model avoids author-side APCs and the equity issues they raise, preserves the workflow of subscription procurement, and is approved as a route to Plan S compliance.
How S2O differs from diamond OA and from a Read-and-Publish deal
S2O is often grouped with equity-oriented OA models, but it is structurally distinct from diamond OA: a diamond journal never charges anyone, while an S2O journal still depends on institutional subscription payments — it simply removes the reader-facing paywall once enough of those payments arrive. It is also distinct from a Read-and-Publish agreement: R&P bundles a library’s reading access with its authors’ publishing rights in one negotiated multi-year price, while S2O is a conditional, single-price, single-journal renewal mechanism with no separate publishing component.
Adoption and the free-rider problem
DOAJ formally recognised S2O with a dedicated “Subscribe-to-Open” label, launched in March 2025, with 61 journals labelled at launch as part of DOAJ’s broader move away from a single Seal toward model-specific labels. S2O’s structural weak point is the free-rider problem: a library that lets its subscription lapse but still benefits once the volume opens gains a free ride at other subscribers’ expense. Publishers mitigate this with short subscription-suspension windows, transparent reporting of which institutions renewed, and appeals to community solidarity rather than access restriction as the enforcement mechanism.
References
- Annual Reviews S2O documentation. Crow R, Gallagher J, Naim K ‘Subscribe to Open: A practical approach to flipping subscription journals’ Learned Publishing 2020. DOAJ blog, ‘Launch of the Subscribe-to-Open (S2O) label’, March 2025.
Also known as
S2O
Machine-readable encodings
Use in your systems
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