What is a data box and who is required to have one?

A data box (datová schránka) is a state-guaranteed electronic tool used for official communication. Think of it as a "digital recorded-delivery letter". It replaces trips to the post office with a blue-striped slip and ensures that your messages to the authorities (and theirs to you) arrive immediately and with clear proof of delivery.

Since 2023, the state automatically sets up data boxes for all entities that have been assigned a Company ID (IČO) (in practice, all entities the state records as economically active). It is therefore mandatory for:

• Legal entities: Companies (s.r.o., a.s.), foundations and unit-owner associations (SVJ)
• Self-employed individuals (OSVČ): Anyone who holds a trade licence
• Liberal professions: Doctors, lawyers, tax advisers, experts and interpreters
• Public authorities: Offices, courts, the police and municipalities

Ignoring your data box is today the most common cause of unnecessary problems for entrepreneurs. Even if you do not log in to the box, the following rules apply:

• The box is active even without you: It is activated automatically on the 15th day after the login details are delivered by post (or on your first login).
• Deemed delivery: A message sent by an authority is considered delivered 10 days after it is placed in the box. It does not matter whether you have opened it – the deadlines run from that moment!
• Fines for the form of submission: If you are required to have a data box, you must, for example, file your tax return electronically. The tax office will automatically impose a fine for a paper submission!

Worth remembering: Not using your data box really does not protect you from the authorities in any way; it only deprives you of control over your business.