A company's name, address and tax ID already exist in the Czech public registry ARES. Here's how to have them filled in automatically instead of retyping them by hand for every new contact.
Almost every Czech company enters the same three fields by hand for new clients or suppliers at least once: company name, registered address and tax ID. Yet this data already exists - in the ARES public registry, maintained by the Ministry of Finance. All you need is the company ID number, and the system can look up the rest itself, without a single manual retype.
What ARES is and what its API returns
ARES (Administrative Register of Economic Subjects) is a public registry that gathers basic information about companies and entrepreneurs registered in Czechia - name, registered address, legal form, tax ID and status. The Ministry of Finance offers a freely available REST API for it, which can be queried by company ID number without needing to log in or use a paid key.
In practice this means: whenever you have a company ID number, one HTTP request gets you back the official company name, registered address and tax ID, exactly as they're recorded in the public registry.
Where this can be automated
In no-code automations like the ones in Apexloop, this lookup is built from standard, general-purpose building blocks - no custom code, just three steps in sequence:
- Trigger - a new record with a company ID number filled in (say, from a form or a manually added contact).
- HTTP node - calls the public ARES API with the ID number from the previous step.
- Record update - the result from the response (name, address, tax ID) gets written back into the record's fields.
The record only has a company ID number so far
A trigger on a new record calls the public ARES API through an HTTP node, and the result automatically fills in the rest of the details - without a single manual retype.
The whole approach is the same general pattern used elsewhere too - a webhook or an HTTP node calls an external service, and a condition decides what happens next. For an ARES lookup, it's worth adding one extra step: if no matching business is found (say, because of a mistyped ID number), the automation can alert whoever created the record right away instead of failing silently.
What you can save this way
- Entering a new contact or client - just the company ID number is enough, the automation fills in the rest of the address and billing details.
- Checking before issuing an invoice - verifying that the billing details on a record match the current state in the registry.
- Bulk-updating old records - for a contacts database without addresses, you can have an automation go through every record with a company ID number and fill in the missing fields all at once.
None of these situations needs a special "ARES connector" - a general HTTP node, which today's no-code automations usually offer, is enough, plus three minutes to put the flow together.
What to watch out for
The public ARES API doesn't require authentication, but it does have reasonable limits on the number of requests - for normal business use (dozens to hundreds of new records a day) that's plenty, while for bulk-querying thousands of records at once it's worth spreading the requests out over time. The registry's data also reflects the official status with a delay after it's recorded, so for freshly registered companies it occasionally happens that a record isn't findable yet - which is why it's worth handling the "business not found" case in the automation too.
The whole flow - from an incoming enquiry through the registry lookup to a job waiting for approval - is described in AI reads the email and creates the job.
Frequently asked questions about automating with ARES
Do I need a key or registration to call the ARES API?
No. The public ARES REST API is available without login and without an API key - all you need is the ID number of the business you're looking up.
Can this fill in the tax ID too, not just the address?
Yes, the ARES response also includes the tax ID if the business is VAT registered and recorded in the registry. The automation can write it in the same step as the name and address.
What happens if the automation is given an invalid or nonexistent company ID number?
A well-built flow should handle this case with a condition - if ARES doesn't return a matching business, the automation can alert the person who created the record to check the ID number by hand, instead of failing silently.