US routing number lookup

Resolve a 9-digit ABA routing number with checksum validation to its institution.

This documentation covers API V1.

Endpoint

Returns the US financial institution behind an ABA routing number, together with the checksum validation result.

http

GET https://api.fincode.example.com/v1/routing/{number}

Parameters

Name	Type	In	Description
number	string	path	The 9-digit ABA routing number, e.g. 021000021.

Example request

bash

curl -s "https://api.fincode.example.com/v1/routing/021000021" \
  -H "Authorization: Bearer sk_test_xxx"

Example response

json

{
  "data": {
    "routing_number": "021000021",
    "checksum_valid": true,
    "bank": {
      "id": "inst_jpmorgan",
      "name_en": "JPMorgan Chase Bank, N.A.",
      "short_name": "JPMorgan Chase",
      "country": "US",
      "website": "https://www.jpmorganchase.com"
    },
    "city": "New York",
    "state": "NY",
    "status": "ACTIVE",
    "source": {
      "name": "ABA routing number registry",
      "source_type": "OFFICIAL",
      "retrieved_at": "2026-09-01"
    }
  },
  "meta": { "request_id": "req_7b1e64d0" }
}

Errors

Code	Description
INVALID_ROUTING	The number is not 9 digits or fails the checksum.
NOT_FOUND	The identifier does not exist in the dataset.
UNAUTHORIZED	Missing or invalid API key.
RATE_LIMITED	Rate limit exceeded — retry after the indicated delay.