Mikrorachunek Checker

What Is a Mikrorachunek?

A mikrorachunek podatkowy is your personal tax payment account in Poland¹. Every person and business registered with Polish tax authorities has one. You use it to pay PIT, CIT, VAT, and other taxes directly to the National Revenue Administration (Krajowa Administracja Skarbowa)².

The number is 26 digits long and follows the Polish NRB bank account format³. It never changes, regardless of where you live or which tax office handles your returns¹. All mikrorachunek accounts are serviced by the National Bank of Poland (NBP).

How the Checker Works

The tool runs three checks on any 26-digit number you enter:

Constant segment check. Positions 3 through 13 must contain 10100071222. This string identifies NBP as the servicing bank (sort code 10100071) and marks the account as a mikrorachunek (suffix 222)⁴³. Any number missing this segment is not a mikrorachunek.

PESEL or NIP extraction. Positions 14 through 26 hold the taxpayer’s PESEL or NIP. The tool reads these digits, identifies which type of identifier is embedded, and runs that identifier’s own validation check.

IBAN check digit verification. The first two digits are check digits calculated with the MOD 97-10 algorithm³. The tool recalculates them and confirms nobody altered or mistyped the number.

Structure of a Mikrorachunek Number

Every mikrorachunek follows the same layout:

Positions 1–2: Check digits, generated by the MOD 97-10 algorithm from the rest of the number³.

Positions 3–10: Bank sort code 10100071, identifying NBP³.

Positions 11–13: The constant 222, marking the account as a mikrorachunek rather than a regular bank account⁴.

Positions 14–26: Your PESEL (11 digits with two leading zeros) or NIP (10 digits with three leading zeros)⁴.

In IBAN format, “PL” appears at the front, giving 28 characters total³.

No single government document spells out this positional breakdown. The structure derives from the legal definition in Art. 61b of the Tax Ordinance⁴ combined with the NRB banking standard published by NBP³.

PESEL or NIP: Which Identifier Is Inside?

Individuals use PESEL. This includes sole proprietors who are not registered for VAT⁵⁶.

Companies and VAT-registered sole proprietors use NIP.

The checker extracts whichever identifier is embedded and tells you which type it found.

Verify Before You Pay

The Ministry of Finance warns taxpayers to use only the official generator at podatki.gov.pl¹⁷. Scammers send fake mikrorachunek numbers by email, SMS, or phone, hoping you will transfer tax payments to their accounts.

If someone sends you a number, paste it into the checker before transferring any money. For definitive confirmation, cross-check the result with the official generator on podatki.gov.pl⁸.

Who Owns This Tax Account Number?

Every mikrorachunek encodes the taxpayer’s PESEL or NIP. Paste the number into the checker, and it extracts the embedded identifier.

For NIP-based numbers, you can look up the business in Poland’s CEIDG or KRS registries. For PESEL-based numbers, public lookups are restricted, but you can confirm whether the extracted PESEL matches a known person.

Regular Polish bank account numbers do not encode owner identity. This reverse lookup only works for mikrorachunek numbers.

Common Questions

What taxes can I pay through my mikrorachunek?

PIT, CIT, and VAT are the main ones. Since October 2025, the list also includes gaming tax (POG), certain surcharges, and other budget receivables².

How do I find my mikrorachunek number?

Use the official generator at podatki.gov.pl⁸. Enter your PESEL or NIP and the tool returns your number instantly. You can also use our mikrorachunek generator.

Is this tool the same as the government generator?

No. The government generator creates your mikrorachunek from a PESEL or NIP⁸. This checker does the reverse: it takes an existing number and verifies whether it is valid.

What should I do if a number fails the check?

Do not use that number for payments. Generate a fresh number from the official generator or contact your tax office (urząd skarbowy) directly.