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EN 301 549harmonised standardEAA

What is a harmonised standard? EN 301 549 explained

What a harmonised standard is under EU law, how one is made, and why EN 301 549 is the harmonised standard for digital accessibility.

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Pavel Charkasau

A harmonised standard is a European standard that the European Commission asked a recognised standards body to write, so that meeting it earns you a presumption of conformity with a specific EU law. That definition is not marketing shorthand. It comes straight from Regulation (EU) No 1025/2012, Article 2(1)(c): "a European standard adopted on the basis of a request made by the Commission for the application of Union harmonisation legislation." Two things make a standard "harmonised" rather than just another technical document. The Commission requested it to support a named law, and its reference has been published in the Official Journal of the European Union. Once both hold, using the standard lets you prove compliance the short way. You show you met its clauses, and the burden of arguing you meet the law shifts off your shoulders.

For digital accessibility, that harmonised standard is EN 301 549. It is cited in the Official Journal for the Web Accessibility Directive, which covers the public sector. It is also the working benchmark for the European Accessibility Act — though the EAA citation is not yet in place, and that distinction matters. Here is how a standard becomes harmonised, and what it actually buys you.

What makes a standard "harmonised"?

Plenty of standards exist that no law points at. ISO publishes thousands. A standard becomes harmonised only in relation to a particular piece of EU legislation, and only through a formal chain.

Start with the ordinary kind. A European standard, in the words of Regulation 1025/2012, is "a standard adopted by a European standardisation organisation" — CEN, CENELEC, or ETSI. Adopting a standard is something these three bodies do all the time, on their own initiative, without any law involved. That is a European standard, not a harmonised one.

The word "harmonised" adds a legal relationship. The Commission has to have requested the standard "for the application of Union harmonisation legislation," and the standard's reference has to sit in the Official Journal. Strip either condition away and the presumption of conformity disappears with it. A draft that the experts finished last month but the Commission has not yet cited is a European standard doing useful work, but it is not yet harmonised for that law. That gap is exactly where accessibility sits in 2026, which I come back to below.

How does a standard become harmonised?

Three steps, in order, and each one is someone else's job.

The Commission issues a standardisation request. Article 10 of Regulation 1025/2012 lets the Commission "request one or several European standardisation organisations to draft a European standard" by a deadline. In older paperwork you will see these called mandates, with an M-number. For accessibility, the current request is M/587, adopted in 2022, asking CEN, CENELEC, and ETSI to revise EN 301 549 to support the European Accessibility Act (European Commission Rolling Plan).

The standards bodies write and adopt it. The technical committees do the drafting, run the public enquiry, and vote. For EN 301 549 this is a joint ETSI, CEN, and CENELEC effort. The output is a finished European standard — but at this point the presumption still does not exist.

The Commission cites it in the Official Journal. Article 10(6) says that when a standard satisfies the requirements it set out to cover, "the Commission shall publish a reference of such harmonised standard without delay" in the Official Journal. That publication is the switch. Before it, you have a good standard. After it, you have a harmonised one, and the legal shortcut is live.

Notice who is missing from those three steps: you. A harmonised standard is built and cited entirely between the Commission and the standards bodies. Your only decision is whether to use it.

What does presumption of conformity actually give you?

It gives you a shortcut and a shift in who has to prove what. Take the European Accessibility Act. Article 15 of Directive (EU) 2019/882 states it plainly: "Products and services which are in conformity with harmonised standards adopted in accordance with Regulation (EU) No 1025/2012 shall be presumed to be in conformity with the corresponding accessibility requirements of this Directive." The Web Accessibility Directive carries the same mechanism in its Article 6.

Without a harmonised standard, you would have to argue from first principles that your service is perceivable, operable, understandable, and robust — the four essential requirements the law borrows from WCAG. With one, you point at the clauses you met and let the presumption carry the rest. A market surveillance authority that wants to challenge you then has to show the standard was not actually met, rather than you having to prove abstract accessibility from scratch.

Two limits are built into the word "presumption." It is rebuttable — a regulator or court can still find that meeting the clauses did not, in this case, deliver an accessible outcome. And it only covers "the corresponding" requirements, meaning the parts of the law the standard maps to. Anything outside that scope stays your problem.

Why is EN 301 549 the harmonised standard for accessibility?

Because it is the one the Commission asked for and cited. EN 301 549, "Accessibility requirements for ICT products and services," is the European standard that translates broad legal duties into testable clauses — web content, software, mobile apps, documents, hardware, and closed products like ticket machines. It leans on WCAG for the web parts and adds requirements WCAG never covered, such as hardware and support documentation.

For the Web Accessibility Directive, the harmonisation is complete and current. EN 301 549 v2.1.2 was first cited in the Official Journal in 2018, and Commission Implementing Decision (EU) 2021/1339 updated that reference to v3.2.1 in August 2021 (European Commission). So a public-sector website that meets the v3.2.1 clauses gets the presumption today, and v3.2.1 is the version that carries it. When a newer version is cited, the presumption moves with the reference.

If you want the clause list in front of you before an audit, our WCAG checklist covers the Chapter 9 web criteria that make up the bulk of what EN 301 549 requires of a website.

Is EN 301 549 a harmonised standard for the EAA yet?

Not yet — and this is the part vendors gloss over. The European Accessibility Act's Article 15 promises a presumption of conformity through harmonised standards, but a promise in the law is not the same as a standard in the Official Journal. As of 2026, no harmonised standard has been cited under the EAA. The Commission's M/587 request tasked the standards bodies with producing one, and a revised EN 301 549 that aligns with WCAG 2.2 reached final draft in mid-2026 (ETSI EN 301 549 V4.1.0, June 2026). Until the Commission cites it, the EAA's presumption-of-conformity route is written but not yet operative.

What does that mean in practice? You do not get to wait. The EAA's obligations apply now; only the shortcut is pending. So you meet the Act's accessibility requirements directly, and you use EN 301 549 as the benchmark for how, because it is plainly the standard the eventual citation will point at. My own view, after building against both regimes: treat EN 301 549 as binding today regardless of the citation. The alternative is guessing at "perceivable, operable, understandable, robust" without a clause list, and that is worse in every way that matters.

What a harmonised standard does not do

It does not make your site accessible on its own, and it does not let a tool declare you conformant. Meeting the clauses is a claim you have to substantiate, and much of EN 301 549 cannot be checked by software. On Deque's data from more than 2,000 audits, automated testing caught about 57% of issues by volume, and estimates based on how many success criteria a tool can even evaluate land closer to 30% (Deque). Focus order, whether alt text is meaningful, whether an error message actually helps — those need a person with a keyboard and a screen reader.

That limit is also why overpromising is dangerous. The US Federal Trade Commission ordered the overlay vendor accessiBe to pay $1 million for representing that its product could make a site WCAG compliant (FTC). A harmonised standard gives you a defensible route to compliance. It does not give anyone the right to say the work is finished before a human has checked it.

Frequently asked questions

What is a harmonised standard in simple terms?

It is a European standard the Commission asked for and then cited in the Official Journal, so that meeting it gives a presumption of conformity with a specific EU law. Without both the request and the citation, it is an ordinary standard with no legal shortcut attached.

Is EN 301 549 a harmonised standard?

Yes, for the Web Accessibility Directive. Version 3.2.1 is cited in the Official Journal via Commission Implementing Decision (EU) 2021/1339. For the European Accessibility Act, no version has been cited yet, so the EAA presumption is still pending.

Does meeting a harmonised standard make me legally compliant?

It gives you a presumption of conformity, not a guarantee. The presumption is rebuttable and only covers the requirements the standard maps to. You still have to substantiate that you actually met the clauses, and much of that needs manual testing.

Are harmonised standards mandatory?

No. Using them is voluntary. You may meet the law another way, but then you carry the full burden of proving it. In practice, for accessibility, EN 301 549 is the only realistic benchmark, so most organisations follow it whether or not the citation is in place for their law.

Which version of EN 301 549 carries the presumption today?

Version 3.2.1, for the Web Accessibility Directive, cited in August 2021. A WCAG 2.2 revision reached final draft in 2026 but has not been cited in the Official Journal, so it does not carry a presumption yet.

Check your site against the standard

A harmonised standard only helps once you know where you stand against its clauses. The web requirements in EN 301 549 map to WCAG, so that is the practical place to start. Run a free scan to clear the machine-detectable checks on your key pages, then work through the manual criteria a scanner cannot judge. You will finish with clause-level evidence to record in an accessibility statement, instead of a guess about whether you meet the standard the law points at.

Pavel Charkasau, founder, wcagc.com. Last updated 14 August 2026.

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