Bulgaria IBAN validator
How the IBAN format works
- Format
- BG + 2 check digits + 4-letter bank code + 4-digit branch code + 2-digit account type + 8-char account number (22 chars)
- Example
- BG80BNBG96611020345678
Things to watch for
- Bank code is 4 letters, not digits
- 22 characters total
^BG[0-9]{2}[A-Z]{4}[0-9]{4}[0-9]{2}[0-9A-Z]{8}$A Bulgarian IBAN is 22 characters: “BG”, two check digits, a 4-letter bank code, a 4-digit branch code, a 2-digit account type code, and an 8-character alphanumeric account number. The 4-letter bank code is the detail most likely to trip people up coming from countries with all-numeric BBANs — in the example BG80BNBG96611020345678, BNBG identifies the bank, and it’s followed immediately by digits for the branch, account type, and account itself. Anyone paying a Bulgarian supplier, receiving a SEPA transfer from an EU counterparty, or filling in a form that asks for an IBAN rather than local account details needs all 22 characters, letters included, exactly as issued.
How this validator works
This tool checks the “BG” prefix, confirms the bank code block is 4 letters, the branch code block is 4 digits, the account type block is 2 digits, and the account number block is 8 alphanumeric characters, then runs the mod-97 checksum (ISO 7064) that Bulgarian banks use to generate a valid IBAN — entirely client-side in your browser, no signup, nothing sent to a server.
What a pass doesn’t tell you
A pass means the IBAN is correctly structured and internally consistent — not that the account exists, is open, or belongs to the payee you expect. This tool does no lookup from the 4-letter bank code to an institution name, and it never contacts a bank or clearing system. If a Bulgarian IBAN fails, check first for a case-typo or substituted character in the 4-letter bank code, or a transposed digit further along — both are easy to introduce when copying by hand.
Scope: Bulgarian IBAN structure and mod-97 checksum validation only — not payment processing, bank-code resolution, or confirming an account is active, none of which a client-side check can establish. Use this validator to catch a typo before a transfer fails; use your bank to confirm the account itself.
Content last reviewed 2026-07-07.
IBAN FAQ
Why does a Bulgarian IBAN start with letters right after the check digits?
Because the bank identifier in a Bulgarian IBAN is a 4-letter code rather than digits — for example BNBG in BG80BNBG96611020345678. It's followed by a 4-digit branch code, a 2-digit account type code, and an 8-character alphanumeric account number, 22 characters in total.
What does the 2-digit 'account type' segment mean?
It's a Bulgarian-specific segment distinguishing categories of account (such as current versus savings) within the BBAN, sitting between the branch code and the account number itself — a segment most other European IBAN formats don't include as a separate block.
Does this tool confirm the 4-letter code matches a real Bulgarian bank?
No. It validates structure and the mod-97 checksum only. The 4-letter code typically mirrors a bank's SWIFT/BIC prefix, but confirming which institution it belongs to, or whether the account is active, requires your bank or the Bulgarian National Bank — not a client-side checker.