Mikrorachunek Checker
Paste a 26-digit Polish tax account number to check whether it matches the official mikrorachunek format. The tool verifies the constant segment 10100071222 in positions 3–13, extracts the embedded PESEL or NIP, and confirms the IBAN check digits. Check a number before making a tax payment. Verify whether a number from an email or SMS is genuine. Identify who a tax account belongs to by reading the PESEL or NIP encoded in it. To generate your mikrorachunek from a PESEL or NIP, use our generator. For official verification, use podatki.gov.pl.
Don't have a mikrorachunek yet? Generate one from your PESEL or NIP number.
Go to Mikrorachunek GeneratorWhat Is a Mikrorachunek?
A mikrorachunek podatkowy is your personal tax account number in Poland [1]. 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) [8].
The number is 26 digits long and follows the Polish NRB bank account format [9]. It never changes, even if you move to a different city or switch tax offices [1]. The National Bank of Poland (NBP) services all mikrorachunek accounts.
If you received a 26-digit number and need to confirm it is a real mikrorachunek before sending money, paste it into the checker above.
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) [3][9]. 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 and tells you which identifier is embedded. It also runs the identifier's own validation check.
IBAN check digit verification. The first two digits are check digits calculated with the MOD 97-10 algorithm [9]. The tool recalculates them and confirms nobody altered or mistyped the number.
Structure of a Mikrorachunek Number
Every mikrorachunek follows the same layout. The 26 digits break down into four segments:
Positions 1 to 2 hold the check digits. The MOD 97-10 algorithm generates them from the rest of the number [9].
Positions 3 to 10 hold the bank sort code: 10100071. This code belongs to NBP [9].
Positions 11 to 13 hold the constant 222. This suffix identifies the account as a mikrorachunek rather than a regular bank account [3].
Positions 14 to 26 hold your PESEL (11 digits with two leading zeros) or NIP (10 digits with three leading zeros) [3].
In IBAN format, "PL" appears at the front, giving 28 characters total [9].
No single government document spells out this positional breakdown. The structure derives from the legal definition in Art. 61b of the Tax Ordinance [3] combined with the NRB banking standard published by NBP [9].
PESEL or NIP: Which Identifier Is Inside?
The rule is straightforward [6][7]:
Individuals use PESEL. This includes sole proprietors who are not registered for VAT.
Companies and VAT-registered sole proprietors use NIP.
The checker extracts whichever identifier is embedded and tells you which type it found. This helps when you receive a mikrorachunek number and want to know whether it belongs to a person or a business.
Verify Before You Pay
The Ministry of Finance warns taxpayers to use only the official generator at podatki.gov.pl [1][5]. Scammers send fake mikrorachunek numbers by email, SMS, or phone, hoping you will transfer tax payments to their accounts.
If someone sends you a mikrorachunek number, paste it into the checker before transferring any money. The tool flags any number that does not match the official format. For definitive confirmation, cross-check the result with the official generator on podatki.gov.pl [2].
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, the identifier confirms the account belongs to a specific individual. Public PESEL 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.
FAQ
What is a mikrorachunek podatkowy?
A mikrorachunek is your personal tax payment account number in Poland. Poland assigns it based on your PESEL or NIP [1]. The number is 26 digits long.
How do I find my mikrorachunek number?
Use the official generator at podatki.gov.pl [2]. Enter your PESEL or NIP and the tool returns your number instantly. You can also use our mikrorachunek generator.
Can I check if a mikrorachunek number is real?
Yes. Paste the 26-digit number into the checker above. It verifies the format, recalculates the IBAN check digits, and extracts the embedded PESEL or NIP.
What taxes do 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 receivables [8].
Does my mikrorachunek number ever change?
No. It stays the same regardless of where you live or which tax office handles your returns [1].
What 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.
Is this tool the same as the government generator?
No. The government generator creates your mikrorachunek from a PESEL or NIP [2]. This checker does the reverse: it takes an existing number and verifies whether it is valid.
References
- Ministry of Finance — Mikrorachunek Podatkowy Main Page — podatki.gov.pl
- Official Mikrorachunek Generator — podatki-arch.mf.gov.pl
- Tax Ordinance — Consolidated Text (Art. 61b) — isap.sejm.gov.pl
- Ministry of Finance — Announcement of Mikrorachunek Launch — gov.pl
- National Revenue Administration (KAS) — Individual Tax Account — gov.pl
- Mikrorachunek Guide for Entrepreneurs — Biznes.gov.pl — biznes.gov.pl
- Regulation on Taxes Payable via Mikrorachunek (Dz.U. 2025 poz. 1305) — isap.sejm.gov.pl
- NBP — Bank Numbering and Account Numbering (NRB/IBAN Standard) — nbp.pl
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