What Is Open Access?

If you are working in a research group, you will hear the term open access early and often. Understanding what it means — and what is expected of you when you publish — is part of being a responsible scientist today. This post breaks it down from the ground up.

What Is Open Access?

Open access (OA) refers to the practice of making scientific research freely and permanently available online, without paywalls, subscription fees, or embargo periods, so that anyone in the world can read, download, and build on it.

The most widely cited definition comes from the Budapest Open Access Initiative (BOAI), which in 2002 defined open access as:

“Free availability on the public internet, permitting any users to read, download, copy, distribute, print, search, or link to the full texts of these articles… without financial, legal, or technical barriers other than those inseparable from gaining access to the internet itself.”

That definition has held up for more than two decades and is still the foundation most funders build their policies on.

Why Does Open Access Matter?

The traditional publishing model works like this: researchers do the work (often with public funding), submit their manuscripts to journals, peer review is done for free by other researchers, and the journal charges universities and institutions thousands of dollars per year in subscription fees to read the results. The public, which often paid for the research through taxes, cannot access it without paying again.

Open access challenges that model. Here is why it matters:

Taxpayer-funded research should be publicly available. Most research in the United States is funded by NIH, NSF, and other federal agencies — meaning it is paid for by the public. It follows that the public should be able to read the results.

It increases scientific impact. Open access articles receive more citations. Research has shown an 8.6% increase in citations for open access publications compared to paywalled ones, rising further when researchers also share their data and code.

It accelerates discovery. When researchers everywhere — not just those at well-funded institutions — can read the latest findings, science moves faster. A researcher in Brazil or Ghana should not be cut off from literature that a researcher at a large American university can access.

It supports reproducibility. When methods, data, and findings are freely available for scrutiny, other researchers can verify and replicate them. This is essential for building a trustworthy scientific record.

It reduces global inequality. Subscription fees are prohibitive for institutions in lower-income countries. Open access levels the playing field, allowing scientists worldwide to participate in and contribute to global knowledge.

What NIH Requires

The National Institutes of Health (NIH) is the largest funder of biomedical research in the world. Its public access policy has been in effect since 2008 and was significantly strengthened in 2024.

Current NIH Public Access Policy (effective December 31, 2025):

All peer-reviewed manuscripts resulting from NIH funding must be deposited in PubMed Central (PMC) upon acceptance for publication
No embargo period — articles must be immediately and freely available (the previous policy allowed a 12-month delay)
Applies to grants, contracts, intramural research, and work by NIH employees
No article processing charges (APCs) are required from authors for PMC deposit
Authors must acknowledge NIH funding and agree to a government use license

If you publish work that includes NIH-funded research, you are required to comply. Non-compliance can affect future funding.

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What NSF Requires

The National Science Foundation (NSF) funds research across all fields of science and engineering. Its public access policy has also moved toward immediate open access.

Current NSF Public Access Policy (effective January 22, 2026):

All peer-reviewed journal articles and juried conference papers from NSF-funded research must be deposited in the NSF Public Access Repository (NSF-PAR)
No embargo period — immediate public access at the time of publication (the previous policy allowed a 12-month delay)
Researchers must include a Data Management and Sharing Plan with all grant proposals
Data underlying publications must be made publicly available with persistent identifiers (DOIs)
No publication costs are imposed on researchers for depositing in NSF-PAR

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Open Access Is Becoming a Global Standard

Open access is no longer just a U.S. policy — it is a worldwide movement. But it is important to understand that requirements vary significantly by country, funder, and institution. There is no single global rule. What is required of you depends on who funded your work.

Plan S — Europe

Plan S is an initiative launched in 2018 by cOAlition S, a consortium of major European research funders. It requires that all research funded by its members be immediately open access upon publication, with no embargo periods, and licensed under Creative Commons (typically CC BY). Major European funders from the Netherlands, UK, France, Germany, Sweden, and others are signatories.

UKRI — United Kingdom

UK Research and Innovation (UKRI), the UK’s primary research funder, implemented a Plan S-aligned policy in 2022. All UKRI-funded research articles must be open access at the time of publication, with CC BY licensing and zero embargo periods.

UNESCO — Global Framework

In 2021, UNESCO adopted the Recommendation on Open Science, the first international standard-setting instrument on open science, ratified by 193 UN member states. It defines open science broadly — covering open access publishing, open data, open methodology, and open source software — and calls on member states to reduce digital and knowledge divides worldwide. It does not impose specific embargo or licensing requirements, recognizing that national contexts differ.

How Countries Vary

Adoption is uneven. Among major research-producing countries, open access rates range widely:

Highest adoption: Sweden (~80% of publications OA), Netherlands (~74%), UK (~66%), Switzerland (~69%)
Lower adoption: India (~19%), China (~30%), Iran (~30%)

Some countries have national mandates; others rely on funder-level policies; some have neither. The policy landscape continues to evolve rapidly — as of 2024, approximately 47% of all scientific publications globally were open access, up from 22% in 2015.

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What This Means in Practice

When you publish research from this group, you will need to:

Identify your funding sources — NIH, NSF, or other funders each have their own requirements
Check the journal’s open access options — many journals offer immediate open access (gold OA), deposit in a repository (green OA), or hybrid models
Deposit your manuscript — if required (e.g., NIH-funded work goes to PubMed Central), do it promptly upon acceptance
Share your data — increasingly, funders require that data underlying publications also be made publicly available

Open access is not just a bureaucratic checkbox. It is a commitment to making science work the way it should — transparently, equitably, and for everyone. Getting into good habits early will serve you throughout your career.

If you have questions about what applies to a specific project, ask before you submit. Requirements are easier to meet when planned for in advance.

icaoberg / What Is Open Access?