Danish IBAN Format (DK): Structure, Registration Number, and Validation Examples

The Danish IBAN is 18 characters long and maps directly from Denmark's domestic banking system: a 4-digit registration number (regnr) identifying the bank or branch, combined with a 10-digit account number. Denmark is a SEPA member through the EU but retains the Danish krone (DKK), making Danish IBANs a common feature of Scandinavian B2B payment flows where euro-to-krone conversion is a routine step.

Danish IBAN at a Glance

• Country code: DK
• Total length: 18 characters (always)
• Format: DKkk rrrr cccccccccc
• BBAN length: 14 digits
• Character types: digits only after the country code

Danish IBAN Structure Explained

1. Country Code — DK (2 characters)

The ISO 3166-1 alpha-2 code for Denmark. Every Danish IBAN begins with DK.

2. Check Digits — kk (2 digits)

Two decimal digits calculated using the MOD-97 algorithm. Standard across all IBANs.

3. Registration Number — rrrr (4 digits)

The registreringsnummer (reg. nr.) is a 4-digit bank or branch identifier. It identifies the bank where the account is held. Examples:

• 0040 — Danske Bank (main)
• 0400 — Jyske Bank
• 0216 — Nordea Danmark
• 9070 — Nykredit Bank

4. Account Number — cccccccccc (10 digits)

The 10-digit account number identifying the individual account. Danish account numbers are always exactly 10 digits in the IBAN; shorter legacy account numbers are zero-padded on the left.

Danish IBAN Example Explained

DK50 0040 0440 1162 43

• Country: DK
• Check digits: 50
• Registration number: 0040 (Danske Bank)
• Account number: 0440116243

Second Example — Jyske Bank

DK22 0400 0012 3456 78

• Country: DK
• Check digits: 22
• Registration number: 0400 (Jyske Bank)
• Account number: 0012345678

How Danish IBAN Validation Works

1. Country code check: First two characters must be exactly DK.
2. Length check: Total character count (spaces removed) must be exactly 18. Danish IBANs are the same length as Dutch IBANs (NL, 18 characters) but have a different structure — the bank code in Dutch IBANs is 4 letters, while Denmark's is 4 digits.
3. Character type check: Positions 3–18 must all be decimal digits. Danish IBANs are fully numeric after the country code.
4. MOD-97 check: Standard modulo 97 computation. Result must equal 1.

The ibanchecker.cash validator validates Danish IBANs and shows the registration number and associated bank name.

Common Danish IBAN Mistakes

Using the Domestic Format Instead of IBAN

Danish bank statements often display the account in the format regnr. 0040 / konto 04401162 (registration number and account number separately). This domestic format is not an IBAN — the full IBAN starting with DK must be used for SEPA and international transfers.

Confusing with Dutch IBANs

Both Danish (DK) and Dutch (NL) IBANs are 18 characters. The difference is in the bank code field: Dutch IBANs have a 4-letter alphabetic code (ABNA, INGB), while Danish IBANs have a 4-digit numeric registration number. A numeric-only 18-character IBAN starting with DK is Danish; one with letters in positions 5–8 is Dutch.

Spaces in Electronic Transmission

Remove all spaces: DK5000400440116243.

Danish IBAN and SEPA

Denmark is an EU member and participates in SEPA, but retains the Danish krone. SEPA Credit Transfers to Danish accounts are denominated in euros; the Danish bank converts to DKK. For DKK-denominated transfers, SWIFT is used. Look up any Danish bank's BIC using the ibanchecker.cash SWIFT directory.

Validating Danish IBANs in Bulk

Finance teams with Nordic suppliers can validate Danish IBANs alongside Norwegian and Swedish ones using the ibanchecker.cash bulk checker. Upload a CSV with up to 100 IBANs and receive per-row validation results.

Last updated: June 2026