San Marino bank code lookup — the BCSM list of operating banks

San Marino uses the Italian ABI code: five digits in positions 6–10 of an SM IBAN, after the CIN letter and before the five-digit CAB. The source is the Banca Centrale della Repubblica di San Marino, which publishes the banks it supervises on one page: name, registered office, ABI code and BIC.

There are four of them, and that is the whole country's banking sector. It is also the reason this page exists rather than a line in a table: San Marino is the one register we serve where an absence means nothing at all.

One call

curl -X POST https://api.ibanforge.com/v1/iban/validate \
  -H "Content-Type: application/json" \
  -d '{"iban": "SM84N0303409800000000270100"}'

{
  "valid": true,
  "bic": {
    "code": "…",
    "source": "Source: Central Bank of the Republic of San Marino, Operating Banks (read by IBANforge on …)",
    "basis": "national_register",
    "authoritative": true
  },
  "bank_code_check": {
    "value": "03034",
    "status": "verified",
    "match": "register",
    "register": "Source: Central Bank of the Republic of San Marino, Operating Banks (read by IBANforge on …). Banks only: …",
    "authoritative": false,
    "institution": {
      "name": "…",
      "street": "…",
      "post_code": "…",
      "town": "…",
      "country": "SM"
    }
  }
}

Read authoritative: false carefully — it is the point

Everywhere else we serve a national register, not_in_register means the code is not allocated and is a strong reason to stop a payment. Not here.

The Central Bank publishes the banks it supervises. It does not publish the allocation of the ABI code space, and nothing on bcsm.sm claims it does. Three facts make that concrete:

• San Marino also licenses payment and e-money institutions that are not banks. At least one holds a San Marino BIC and settles through EBA STEP2, and it is not on this page.
• The official San Marino example IBAN, SM86 U032 2509 8000 0000 0270 100, carries the ABI code 03225 — which is not on this page either.
• The page is titled operating banks, and that is exactly what it is.

So a code we find names its holder, and a code we do not find gets the answer San Marino has always given: not_in_register with reason absent_from_reference_data, authoritative: false. Never not_allocated.

This is the opposite of the Austrian and Slovak story, where the official example IBAN pointing at an unlisted code is a finding, because those registers allocate. Here it is not a finding — it is the register minding its own scope.

Two flags that disagree, on purpose

Note the block above: bank_code_check.authoritative is false while bic.authoritative is true. They answer different questions and San Marino is where they part company.

• The code space is not the Central Bank's to settle here, so the verdict is not authoritative.
• The BIC beside a code it does list is its own pairing — the Central Bank printed those two values on the same line — so bic.basis is national_register and the BIC may be stored and settled against.

Switzerland is the mirror image: the SIX register settles the bank code while the BIC beside it comes from our curated map.

What the list publishes

Freshness and the citation

The BCSM publishes no edition number and no revision date, so as_of is the day we read the page and the credit says so in words: Source: Central Bank of the Republic of San Marino, Operating Banks (read by IBANforge on …). A bare date there would read as the Central Bank's own and overstate it.

The Central Bank has confirmed this use in writing. bcsm.sm does not publish terms of use, so we asked. On 16 October 2026 the Central Bank of the Republic of San Marino answered our request of 7 September: naming the bank behind a San Marino IBAN from its Operating Banks page, including for paying customers, is acceptable provided that the information is accurately reproduced, appropriately attributed to its source, and not presented in a misleading manner. It accepted the attribution above, with the date the page was read. It also took note that a code missing from the list is never presented as proof that the code does not exist, which is what authoritative: false says. Its e-mail was sent in good faith and creates no obligation for the Bank: it is a written confirmation that this use is acceptable on those conditions, not a licence. It concerns the use we described, in the answers of the API, which serve one record per request; the list itself is not republished. See data sources.

The honest limits

• We check the ABI code, never the account or its holder. And here, only in the positive direction.
• A miss is not a denial. Repeated because it is the single thing to take away.
• Institution, not branch. The CAB identifies a branch; the BCSM list does not enumerate branches, and we never deny on it.
• Four banks is not the four payment providers of San Marino. Non-bank institutions are licensed separately and are not on this page.

Related: What "verified" means · Data sources & provenance · IBAN to BIC · Slovak bank codes · The four San Marino banks