Journal Embargo Periods Explained: When Does a Paywalled Paper Become Free?

You look up a recent paper and find no free copy. A year later, one has appeared. The reason is usually an embargo: a waiting period the publisher sets before the authors may share their paper publicly.

What an embargo is

Most subscription journals let authors place a copy of their paper in a public repository. This is the route known as green open access, described in our guide to the kinds of open access. Many publishers attach a condition: the copy may not be made public until a set time after publication. That time is the embargo period. Publishers use it to protect subscriptions, on the reasoning that libraries would cancel if every paper were free on day one.

The embargo normally applies to the accepted manuscript, the peer-reviewed text before typesetting. The published PDF usually cannot be shared publicly at all, and preprints can usually be shared at any time.

How long embargoes last

It varies by publisher, by journal and by subject.

• Six to twelve months is typical in science, technology and medicine. Nature's subscription journals, for example, allow public release six months after publication.
• Twelve to twenty-four months is common in the humanities and social sciences, where articles are read over a longer period.
• No embargo applies at some publishers and for some places. Many allow the accepted manuscript on the author's personal website immediately, even when repositories have to wait.

Why some papers are free straight away

• The paper is open access. The authors or their funder paid for it to be free on the publisher's site.
• There is a preprint. Preprints are posted before or at submission and are not covered by the embargo.
• The funder requires it. Papers funded by the US National Institutes of Health and accepted since July 2025 must be free in PubMed Central on publication, with no embargo. Several European funders have similar rules.

How to find out a journal's embargo

A free service called Open policy finder, run by the UK organisation Jisc, lists the sharing rules for thousands of journals. It was previously known as Sherpa Romeo. Search for the journal and it shows which version of a paper can be shared, where, and after how long.

The journal's own website gives the same information, usually on a page about self-archiving, sharing or open-access policy.

What you can do during an embargo

An embargo restricts public posting. It does not stop the other legal routes.

• Look for a preprint. Paste the DOI, link or title into the finder on our home page. Preprints are listed with other free copies.
• Ask the author. Authors may share their paper privately at any time. Our guide has a template for the email.
• Use a library. See getting papers through a library.
• Check again later. Many repositories hold the paper already and release it automatically on the day the embargo ends.

Are embargoes going away?

They are getting shorter and rarer. Funders in the United States, the United Kingdom and Europe increasingly require a free copy at the moment of publication, and publishers have been adapting their policies to fit. For new research the trend is towards immediate access. For older papers, any embargo has long since passed, so if a paper from several years ago has no free copy, the cause is more likely that no one deposited one.