Schema.org's new Credential class is a trust signal for Irish trades

If you are an electrician, a gas installer, a solicitor or an architect, your most valuable marketing asset is the badge on your van or your office wall. RECI. RGI. Law Society. RIAI. Those acronyms are how Irish customers know you have not just rocked up off the boat.

An AI search engine cannot read the badge. It cannot open the JPG of the green tick on your homepage and decode that you are on the Register of Electrical Contractors of Ireland. It can read JSON-LD. And until last month, schema.org did not have a clean way to express what you were registered for if it was not an academic qualification.

What shipped on 19 March

Schema.org Version 30.0 was published on 19 March 2026. Most of the release notes are infrastructure tidy-ups, but one change is genuinely useful for service businesses: the vocabulary now has a top-level Credential class. The older EducationalOccupationalCredential — designed for diplomas and degrees — has been re-parented as a subclass of it. The new top-level type is described as "a certificate used to verify the identity of a person or entity". That is exactly what an Irish trade register is.

Credential ships with four properties that map onto how Irish registers actually work:

• credentialCategory — the kind of credential, e.g. "registration", "licence", "certification".
• recognizedBy — the Organization that issues or maintains the register.
• validFor — how long the registration lasts.
• validIn — the geographic area in which it applies.

It pairs with the existing hasCredential property on Person and Organization. Until v30, pointing hasCredential at anything other than an educational award was a stretch of the spec. As of last month it is the textbook use.

Why this matters for AI search

AI Overviews, ChatGPT browsing, Gemini and Perplexity are picky about which sources they cite for queries with regulatory or safety implications — gas works, electrical certification, conveyancing, tax advice. Those systems lean on schema markup as a machine-readable signal of who is who and what they are allowed to do. Search Engine Land documented the same pattern for local visibility across Google and AI earlier this year: structured data is the trust layer the models actually parse.

When a user asks "find a registered gas installer in Cork", the system is scanning for an Organization whose hasCredential points at an RGI registration recognised by Gas Networks Ireland and valid in Ireland. If your site has the markup, you are a candidate. If it does not, you are a paragraph of marketing copy that the model has to take a guess on.

A logo on your homepage tells humans you are registered. JSON-LD tells the machines — and the machines are the ones writing the answer now.

The shape for an Irish trade

The pattern is small. Inside your existing Organization or LocalBusiness JSON-LD block, add a hasCredential entry. Set credentialCategory to "registration", give the credential a name matching what the issuing body actually calls it (for example "Registered Electrical Contractor"), and set recognizedBy to a nested Organization with the body's name and homepage URL. Add validIn with a Country of "Ireland" so the model has no doubt about jurisdiction.

If you hold more than one — say a builder with both CIRI registration (mandatory for building providers since January 2026) and a Failte Ireland Quality Mark — make hasCredential an array. Each entry is independent and each one is another piece of evidence the model can use to disambiguate you from a same-named operator in another county.

Who should ship this this week

Any Irish SME whose customers care about a register:

• Electricians registered with Safe Electric (RECI).
• Gas installers registered with the RGI scheme under Gas Networks Ireland.
• Plumbers, oil and heating engineers under APHCI or OFTEC Ireland.
• Architects on the RIAI register, engineers under Engineers Ireland, surveyors under SCSI.
• Solicitors on the Law Society of Ireland roll, barristers on the Bar of Ireland's panel.
• Accountants and tax advisors with Chartered Accountants Ireland, ACCA, or the Irish Tax Institute.
• Childcare providers registered with Tusla and tourism operators with a Failte Ireland approval.

If a logo on your homepage is part of how you win business, that logo deserves a JSON-LD twin.

One caveat — and one cross-reference

Google has not announced a rich-result feature on top of Credential, so adding this markup will not, on its own, change how your listing looks in a blue-link SERP. The win is upstream. The same shift we covered after the March 2026 core update applies here: schema is now an entity-trust signal for AI products, not just a visual trigger for the SERP. V30 hands you a cleaner way to participate in that trust layer.

It is the kind of edit you can ship before lunch on a Tuesday. Validate it in the Schema Markup Validator, push it live, and forget about it. Your registration was already true. Now it is also legible.