Free tool
CRO number lookup: search an Irish company by its CRO number
Search a CRO number and get the Irish company behind it from the Companies Registration Office (CRO): name, company type and status, live. A CRO number is the company number the CRO gives every company it incorporates in Ireland; it has no check digit, so the register is the only test.
The same lookup with curl
curl "https://api.prometiam.com/functions/v1/risk-api/companies/search?company_number=104547&country=IE" \ -H "Authorization: Bearer rk_live_your_api_key"
What a CRO number is
The Companies Registration Office assigns a number to every company it incorporates, in sequence, starting from the nineteenth-century register that Ireland inherited. Numbers are up to six digits and carry no check digit, so a wrong digit simply points at another company — the register lookup is the only test that exists.
Irish company types read from the name suffix: LTD private company limited by shares, DAC designated activity company, PLC, CLG company limited by guarantee, ULC unlimited company. Business names and sole traders are registered separately and are not companies.
What the lookup returns
The lookup sends the number to the Prometiam API, which holds the CRO register, and returns the company name, type and current status. A name search runs when the input is not a number.
The full company record is one call away with a free trial key — 500 credits over 14 days, card required, nothing charged for 14 days. For Ireland that includes the strike-off list flag, and a company can be put on watch for changes to its register entry. Ireland is served at company level: no officers, register-change events only, from 14 Oct 2026, and it is not one of the sixteen insolvency markets.
FAQ
What is a CRO number?
A CRO number is the company number (company registration number) that the Companies Registration Office gives a company when it is incorporated in Ireland. It is a plain number with no check digit, and it is not a tax or VAT number.
What does CRO stand for in Ireland?
CRO stands for Companies Registration Office, the State register of Irish companies and business names. “CRO Ireland” and “CRO company” in a search mean a company registered there.
How do I find a company’s CRO number?
Type the company name in the box above: the name search returns matching Irish companies with their CRO numbers. In code, GET /companies/search?name=Ryanair&country=IE returns the same list.
Does an Irish company also have a tax number?
Yes, a tax reference from Revenue, and a VAT number when registered. Neither is on the public register; the CRO number is.
Why does a number return nothing?
The register covers companies; business names, partnerships and sole traders are outside it. A company incorporated in the last few days may not be there yet either. Try the name search.
Can I do this in code?
Yes: GET /companies/search?company_number=104547&country=IE with an API key returns the same record as JSON; the free trial covers 500 credits over 14 days.