Determines the SWIFT BIC of an IBAN. Currently supports IBANs from the following countries: Austria, Belgium, Germany, Spain, France, Lithuania, Luxembourg, Netherlands. Inspired by sigalor/iban-to-bic.

Getting started

Depend on it

flutter pub add iban_to_bic

Import it

import 'package:iban_to_bic/iban_to_bic.dart';

Usage

ibanToBic returns a sealed IbanLookupResult. Pattern-match on it to handle every case exhaustively — no exceptions, no surprise nulls:

import 'package:iban_to_bic/iban_to_bic.dart';

void main() {
  final result = ibanToBic('DE64 5001 0517 9423 8144 35');

  switch (result) {
    case BicFound(:final bic):
      print(bic.value);           // INGDDEFFXXX
      print(bic.bankShortName);   // ING-DiBa
      print(bic.bankLocation);    // Frankfurt am Main
    case InvalidIban(:final iban, :final reason):
      print('Invalid ($reason): $iban');
    case UnsupportedCountry(:final countryCode):
      print('No data for: $countryCode');
    case UnknownBank(:final countryCode, :final bankCode):
      print('Unknown bank $bankCode in $countryCode');
  }
}

Sync vs. async

Bank-code datasets ship as JSON assets and are loaded lazily, so the default path is async. Two APIs:

// Async — no setup required:
final result = await ibanToBicAsync('DE64 5001 0517 9423 8144 35');

// Sync — call preload first (e.g. from main()):
await preloadIbanToBic(['DE', 'NL']);
final result = ibanToBic('DE64 5001 0517 9423 8144 35');

Calling the sync ibanToBic for a country that hasn't been preloaded throws StateError. If startup latency matters more than first-call latency, preload; otherwise just use the async variant.

Extending with custom data

Implement SyncBicResolver for in-memory data, or BicResolver (returns FutureOr<Bic?>) for async sources — an overlay on top of the built-in maps, a corporate registry, the ECB directory, etc.

class EcbResolver implements BicResolver {
  @override
  Future<Bic?> resolve(String bankCode) async =>
      await httpClient.fetchBic(bankCode);
}

final lookup = IbanToBic(countries: {
  'DE': CountrySpec(
    bankCodeStart: 4,
    bankCodeEnd: 12,
    resolver: EcbResolver(),
  ),
});
await lookup.lookup('DE64 5001 0517 9423 8144 35');

Supported countries