Company ID number

What it means

The IČO is the eight-digit organisation identifier. It is assigned when the entity comes into existence and does not change when the name, seat or scope of business does.

It is the key to public registers: it finds the company in the commercial register, the trade register and the register of financial statements.

It is not only companies that have an IČO. One is also assigned to a sole trader, a civic association, a foundation or the branch of a foreign company. A sole trader has a single IČO however many trade licences they hold, while an employee or an ordinary private person has none at all, so it may legitimately be missing from a document issued by a private individual.

How it works in practice

The IČO belongs on invoices, orders and contracts. Checking a new partner starts there: incorporation date, director, seat, statements filed and any enforcement proceedings.

It is not the DIČ nor the VAT number. Foreign partners often ask for one and receive another, which then complicates their VIES checks and their bookkeeping.

We set up a new partner in the accounting system from the IČO: the name, seat and other numbers are pulled from the register, not from an e-mail signature. That removes garbled names and old addresses on invoices that would later need a corrective invoice. For long-standing partners the data is compared with the register at least once a year.

What to watch out for

The IČO of a dissolved company is never reassigned, but it lingers in old databases. So the register is checked before invoicing, not a record sitting in an internal system from years ago.

An unchanging IČO can hide a material change. A company with the same number may have a new member, a new director and quite different results from a year ago, so a check also looks at the history of register entries. After a merger, on the other hand, the dissolved company ceases to exist along with its IČO, and invoices, contracts and payments have to move to the successor.