Docs/APIs/Routing Number Lookup

Routing Number Lookup

Lookup Routing Number Bank

OperationalCredits 10 per callp50 127msFinanceStar

Overview

A routing number validation API for ACH payment forms, payroll and payout onboarding. Send a nine-digit US routing number: input that fails the ABA mod-10 check digit is rejected with a 400 before any lookup, and a valid number returns the bank name from a routing number database that is refreshed on a weekly cycle. Each match includes the routing type (primary, thrift, electronic or government), the Federal Reserve district by name and number, and, for banks that publish a routing number list by state, the states the bank assigns the number to. Paid plans add the registered street address, city and ZIP code, office and record-type codes, and the successor routing number when a bank has retired one.

Live Test Routing Number Lookup API →

Endpoint

One host, one path per API. The block below shows this call in four languages; every one of them is the same HTTP request. Making requests covers the timeouts, retries and parameter rules that apply to all of them. The SDKs wrap the same call in a typed client.

GEThttps://api.apiverve.com/v1/routinglookup
curl "https://api.apiverve.com/v1/routinglookup?routing=121000358" \
  -H "x-api-key: your_api_key_here"

Replace your_api_key_here with the key from your dashboard. When the inputs arrive as a list rather than one at a time, batch requests run up to 200 of them through this same API in a single call.

Authentication

Send your key in the x-api-key header. That is the only auth step — there is no token exchange and no per-endpoint scope to configure. Authentication covers creating, rotating and revoking keys.

401 is the only auth verdict

A 401 means the key is missing, invalid or expired. A 403 means the key is valid but not permitted here — blocked by a key restriction or an IP allow-list. Running out of credits is a 429.

Parameters

Sent in the query string. Premium parameters are accepted on every plan but only take effect on plans that include them.

ParameterTypeDescription
routingRequiredstringThe routing number to lookup information about
length 9–9

Response

Every API returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape. Response format covers the envelope, the other output formats and how premium fields are withheld.

Sample response
{
  "status": "ok",
  "error": null,
  "data": {
    "routing_number": "121000358",
    "office_code": "O",
    "record_type_code": "1",
    "new_routing_number": "000000000",
    "bank": "BANK OF AMERICA, N.A.",
    "address": "8001 VILLA PARK DRIVE",
    "city": "HENRICO",
    "state": "VA",
    "zip": "23228",
    "zip_extension": "0000",
    "country": "US",
    "federal_reserve_district": "San Francisco",
    "federal_reserve_district_number": 12,
    "federal_reserve_states": [
      "AK",
      "AS",
      "AZ",
      "CA",
      "GU",
      "HI",
      "ID",
      "MP",
      "NV",
      "OR",
      "UT",
      "WA"
    ],
    "address_in_district": false,
    "states_served": [
      "CA"
    ],
    "latitude": 37.621745,
    "longitude": -77.48896,
    "timezone": "America/New_York",
    "routing_type": "primary",
    "is_valid_checksum": true,
    "routing_analysis": {
      "is_head_office": true,
      "is_branch": false,
      "is_federal_reserve_bank": false,
      "is_active": true,
      "replaced_by": null
    }
  }
}

Response fields

Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.

FieldTypeExampleDescription
routing_numberstring"121000358"The ABA routing number for the bank
office_codePremiumstring"O"Office code designating the main office or branch location
record_type_codePremiumstring"1"Record type code indicating transaction type classification
new_routing_numberPremiumstring"000000000"New routing number if the bank has been updated
bankstring"BANK OF AMERICA, N.A."Name of the financial institution or bank
addressPremiumstring"8001 VILLA PARK DRIVE"Street address the bank registered with the Federal Reserve for this routing number; national banks often use one central office for numbers in many states
cityPremiumstring"HENRICO"City of the bank's registered address for this routing number
statestring"VA"Two-letter state of the bank's registered address; can differ from where the routing number is used (see address_in_district)
zipPremiumstring"23228"Five-digit postal code of the bank's registered address
zip_extensionPremiumstring"0000"Four-digit ZIP code extension for more precise location
countrystring"US"Country code (ISO 3166-1 alpha-2 format)
federal_reserve_districtstring"San Francisco"Federal Reserve district (e.g. San Francisco) derived from the routing number's first two digits; null for government or traveler's-cheque prefixes
federal_reserve_district_numbernumber12Federal Reserve district number (1 Boston to 12 San Francisco) from the routing number's first two digits, with thrift and electronic prefixes folded back to their district; null for government or traveler's-cheque prefixes
federal_reserve_statesarray[AK, ...]Two-letter codes of the states and territories in the routing number's Federal Reserve district, i.e. where the number is issued; null for government or traveler's-cheque prefixes
address_in_districtbooleanfalseFalse when the registered address is outside the routing number's Federal Reserve district, typically a national bank's central office; null when there is no district or state
states_servedarray[CA]States where the bank itself tells customers to use this number for checking, ACH and direct deposit, from the bank's published routing-number list; null when the bank publishes no by-state list or the number is not on it (e.g. a wire-only number)
latitudePremiumnumber37.621745Latitude of the bank office: the centre of its ZIP code, or of its city when the ZIP is one a large bank uses only for its own mail; null when neither can be placed
longitudePremiumnumber-77.48896Longitude of the centre of the bank office's ZIP code; null whenever latitude is null
timezonestring"America/New_York"IANA time zone of the bank office (e.g. America/Chicago), useful for cut-off times; null whenever latitude is null
routing_typestring"primary"Routing category derived from the routing number prefix: primary, thrift, electronic, government, or travelers_cheque
is_valid_checksumbooleantrueWhether the routing number passes the ABA mod-10 checksum
routing_analysisPremiumobject{...}Plain-language interpretation of the FRB office and record-type codes: head office vs branch, whether it is a Federal Reserve Bank, active vs superseded, and the replacement routing number if the institution was reassigned
is_head_officePremiumbooleantrueThe routing number belongs to the institution's head office (office code O)
is_branchPremiumbooleanfalseThe routing number belongs to a branch office (office code B)
is_federal_reserve_bankPremiumbooleanfalseThe routing number belongs to a Federal Reserve Bank itself (record type 0)
is_activePremiumbooleantrueThe routing number is in use; false when it has been superseded (record type 2)
replaced_byPremiumobjectnullThe routing number to use instead when this one has been superseded; null while it is active

Errors

Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change. Error handling covers the full status list and which of them are worth retrying.

StatusMeaningWhat to do
400Input was rejectedRead error; it names the parameter.
401Key missing or invalidCheck the header name and the key value.
403Key valid, but not permittedA key restriction or IP allow-list; see key scoping.
429Rate limited, or out of creditsRead error to tell them apart; see rate limits.

Use cases

Direct Deposit Setup
When onboarding new hires, payroll systems validate the entered routing number and auto-fill the financial institution name before issuing paychecks.
ACH Transfer Verification
To prevent transfer rejections, payment processors test mod-10 checksums and confirm the receiving bank matches customer paperwork before scheduling debits.
Accounting Vendor Onboarding
Procurement teams verify supplier banking details during vendor registration to catch typos and detect obsolete routing numbers before sending disbursements.
Merchant Account Enrollment
Reject mistyped routing numbers during merchant signup and show the bank name back to the applicant, so a wrong digit is caught before the first settlement instead of after a returned payment.

Other ways to use Routing Number Lookup

Set up Routing Number Lookup on APIVerve, or reach the same source a different way. Your APIVerve account and credits work on all of them — one key, one balance.

Give it to an AI agentConnect over MCP and your agent calls it as a native tool — Claude, Cursor, ChatGPT.VerveKit →Reference →
Google Sheets or ExcelA =VERVE() formula fills a column — no script, no export, recalculates in place.VerveSheets →Reference →
Ground an agent on itA cited, machine-checkable fact your model can't produce on its own.VerveContext →Reference →

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