Tax profile and company data from public registers
Getting started. Content verified: 13 October 2026.
JPK_FA, JPK_MAG and JPK_KR_PD files and PIT and CIT returns require data that is not on the invoice: an address with voivodeship, county and municipality, the tax office code, the form of taxation or OSS information. The "Company details and tax profile" wizard collects it in one place, and fetches part of it for you from public registers.
Where the data comes from
- The Ministry of Finance VAT taxpayer register: name, address, VAT status, REGON and KRS number. Always used, with no configuration.
- KRS: for companies we fetch the registered office and address with voivodeship, county and municipality, the legal form, the share capital and the registry court.
- CEIDG and GUS BIR1: for sole proprietorships, with a full structured address. These sources work when the administrator of your Zaksio installation configures a key for them; without a key they are skipped and you complete the data manually.
We cache the result for 24 hours so as not to query the registers unnecessarily, and we limit the number of queries from one company per hour. The personal data of a sole proprietor does not go into the system logs.
Step by step
- On the dashboard, in the "First steps" card, click "Complete profile" next to the "Complete your tax profile" step.
- Enter the NIP and click "Fetch data from registers". If the NIP has an invalid checksum, the registers are not queried.
- In the "Is this your company?" section, check the name, legal form, address, REGON and business start date. Correct every field that does not match. Missing fields, e.g. voivodeship, county and municipality, are clearly marked.
- In the "Tax profile" section, answer the questions that cannot be read from the registers: VAT status (active or exempt), form of taxation, frequency of advances, VAT-UE, OSS and IOSS, and the flat-rate tax rate, if flat-rate tax was chosen.
- Choose the tax office from the list or enter its code. We suggest it based on the company address.
- Tick the confirmation that the data matches the actual state of affairs, and click "Save and complete step".
The progress bar in the wizard shows how many mandatory items have been completed. The "Complete your tax profile" step in First steps is ticked off once all the data is saved. It blocks only completion of the step itself, not work in the rest of the app.
Companies and sole proprietorships
- Limited liability or joint-stock company: we save the KRS number, share capital and registry court so they can be used in documents. The company is taxed through CIT (standard rate, small taxpayer or Estonian CIT).
- Sole proprietorship: taxed through PIT (progressive scale, flat tax or flat-rate tax). You can fill in the owner's first name, surname and date of birth, because they are needed in PIT returns.
Tax office code check
The office code must come from the Ministry of Finance dictionary that applies to the file schema. PIT forms allow only offices other than specialised ones (e.g. the Masovian office 1471 is not allowed in PIT), while JPK and CIT files accept the full list. We also check that the code matches the voivodeship of the company address.
- In the wizard, a non-matching code does not let you complete the step. You will see the reason and a button with the correct code, if it can be unambiguously determined from the address.
- When generating JPK_V7, JPK_FA, JPK_MAG, JPK_KR_PD, VAT-UE, PIT and CIT, an invalid code results in the message "We will not generate the file" with a hint of the correct value, instead of a file that does not match the schema.
- You can correct the office code in the wizard or in Settings, the "Taxes (JPK)" tab.