IBAN format · NL

Netherlands IBAN format: 18 characters.

Netherlands IBANs have 18 characters: the country code NL, two check digits and a 14-character BBAN, the national account number, laid out as 4!a10!n.

Netherlands IBAN structure

NL91ABNA0417164300

Country code: NL
Check digits: 91
Bank code: ABNA
Account: 0417164300

Parts of a Netherlands IBAN and their positions
Positions	Part	In the example
1–2	Country code	NL
3–4	Check digits	91
5–8	Bank code	ABNA
9–18	Account	0417164300

The BBAN, segment by segment

The registry writes the BBAN in SWIFT notation: n is a digit, a an upper-case letter, c a letter or digit, and the ! means a fixed length. 4!a10!n reads:

The Netherlands BBAN format, segment by segment
Positions	Notation	Holds	Example
5–8	4!a	4 upper-case lettersBank code: the first four letters of the bank’s BIC	ABNA
9–18	10!n	10 digitsAccount number	0417164300

Netherlands IBAN example

NL91 ABNA 0417 1643 00 is the sample the SWIFT IBAN Registry publishes for Netherlands: a well-formed IBAN for showing the format, not a real account. Written electronically it has no spaces (NL91ABNA0417164300); on paper it is printed in groups of four.

Its check digits, worked through with ISO 7064 mod 97-10:

Move the country code and check digits to the end
ABNA0417164300NL91
Replace each letter with two digits (A = 10 … Z = 35)
A = 10, B = 11, N = 23, L = 21
101123100417164300232191
Divide that number by 97 and keep the remainder
Remainder 1. A valid IBAN always leaves 1, so the check digits are right.
Where the check digits come from
Put 00 in their place (NL00…), repeat steps 1–3: remainder 7. The check digits are 98 − 7 = 91.

SEPA

Netherlands is in the Single Euro Payments Area, so SEPA credit transfers and direct debits can reach NL IBANs; whether a given bank takes part is up to that bank.

What the format can and can’t tell you

Valid means the structure and check digits are right — not that the account exists or can receive payments.
National check digits inside the BBAN (e.g. the French RIB key, or the Spanish, Belgian and Italian CIN digits) are not verified.
Bank and branch codes are read from their positions; they are not looked up in a bank directory.

Check NL IBANs from code or an AI agent

REST · GET · no key

curl -s 'https://payopskit.com/api/v1/iban/NL91ABNA0417164300'

MCP · tools/call · validate_iban

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "validate_iban",
    "arguments": {
      "iban": "NL91ABNA0417164300"
    }
  }
}

Response (JSON)

{
  "input": "NL91ABNA0417164300",
  "iban": "NL91ABNA0417164300",
  "print": "NL91 ABNA 0417 1643 00",
  "valid": true,
  "country": {
    "code": "NL",
    "name": "Netherlands",
    "sepa": true,
    "sepaNote": null
  },
  "checkDigits": "91",
  "expectedCheckDigits": "91",
  "length": {
    "actual": 18,
    "expected": 18
  },
  "bban": "ABNA0417164300",
  "bbanFormat": "4!a10!n",
  "bankCode": "ABNA",
  "branchCode": null,
  "parts": [
    {
      "label": "Country code",
      "value": "NL",
      "start": 0,
      "end": 2,
      "kind": "country"
    },
    {
      "label": "Check digits",
      "value": "91",
      "start": 2,
      "end": 4,
      "kind": "check"
    },
    {
      "label": "Bank code",
      "value": "ABNA",
      "start": 4,
      "end": 8,
      "kind": "bank"
    },
    {
      "label": "Account",
      "value": "0417164300",
      "start": 8,
      "end": 18,
      "kind": "account"
    }
  ],
  "checks": {
    "characters": true,
    "country": true,
    "length": true,
    "bbanFormat": true,
    "checksum": true
  },
  "errors": [],
  "notes": [
    "Valid means the structure and check digits are right — not that the account exists or can receive payments.",
    "National check digits inside the BBAN (e.g. the French RIB key, or the Spanish, Belgian and Italian CIN digits) are not verified."
  ]
}

The MCP server is at /mcp (Streamable HTTP, no key); the API and MCP docs show how to connect Claude, Cursor or VS Code.

From a national account number: GET /api/v1/iban/check-digits?country=NL&bban=… or the MCP tool compute_iban_check_digits computes the check digits and the whole IBAN.

Other 18-character IBANs

The same length doesn’t mean the same structure: compare the BBAN formats. All IBAN formats and lengths

Source: the SWIFT IBAN Registry (ISO 13616), transcribed and checked against each country’s registry example; the positions of bank and branch codes are given only where the registry’s are well established. The SWIFT IBAN Registry is the authority. Informational only.