Routing Number Lookup API

GET

Confirm the bank and state behind any US routing number.

Routing Number Lookup verifies US ABA routing numbers to confirm bank names, states, and checksum validity. It identifies the routing type and Federal Reserve district, while paid plans add full street addresses, branch details, and replacement numbers.

Try it — live request, no key required

Request

GETapi.apiverve.com/v1/routinglookup?routing=121000358

Query parameters

routingstring

Verification

Format

No key required to try it. Get a key to use it in your app.

Example

{
  "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",
    "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
    }
  }
}

About the Routing Number Lookup API

Pass any nine-digit US routing number to test its mod-10 checksum and look up directory records updated daily. The service categorizes the prefix as primary, thrift, electronic, or government, and identifies the Federal Reserve district. Paid plans add full branch street addresses, city and postal codes, office codes, and updated routing numbers for merged institutions.

What people use it for

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: Flag invalid or non-standard bank routing numbers during merchant signup workflows to block fraudulent accounts and reduce settlement errors.

Ways to call it

One endpoint, many ways in — REST with JSON, XML, YAML and CSV, plus GraphQL and an MCP interface for AI agents.

JSON: Default REST response
XML: Markup format
YAML: Human-readable
CSV: Tabular export
GraphQL: Query language
MCP: For AI agents

View all integrations →

Other ways to use Routing Number Lookup

Same data, same APIVerve account, same credit balance — one key works on all of them.

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

Questions.

Common questions about the Routing Number Lookup API.

Read the docs →

Does this work for banks outside the United States?

No. The API covers United States financial institutions that use standard ABA routing transit numbers. It does not support international banking identifiers such as IBAN, SWIFT, or BIC codes.

Which plan fits 10,000 routing number lookups a month?

The Starter plan easily covers this volume. At 10 credits per call, 10,000 lookups consume 100,000 credits, exactly half of the 200,000 monthly credits included on Starter. That volume works out to about $0.0015 per lookup, or $1.50 per 1,000 calls. The Free plan provides 20 calls per month for testing.

Are the street address and office code included on the Free plan?

No. The Free plan returns basic details including the bank name, state, routing type, and checksum validity. Access to the physical street address, city, ZIP code, office code, record type code, replacement routing numbers, and routing analysis requires any paid subscription starting with Starter.

How frequently is the bank routing directory updated?

The routing directory updates daily. Every plan receives recent institutional changes; paid plans also receive updated office designations and successor routing numbers when banks merge or restructure.

What does the response show for government or non-standard routing numbers?

For government routing numbers and non-district issuers, the Federal Reserve district field returns null. The response also categorizes the entry under its routing type, identifying whether the number represents a primary bank, thrift, electronic institution, government agency, or traveler's cheque issuer.

Can I use this data to verify bank details in my payment checkout?

Yes, as long as you are subscribed to a paid plan. Commercial use is not allowed on the Free plan. You may display and use the bank details inside your checkout or onboarding workflows, but you cannot resell or redistribute the raw routing dataset.

Request parameters — GET /v1/routinglookup

Sent in the query string. Premium parameters are accepted on every plan but only take effect on plans that include them. Anything not listed here is dropped rather than passed through.

Required

Parameter	Type	Example	Description
`routing`Required	string	`121000358`	The routing number to lookup information about length 9-9

Example request

1
2

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

Authentication

Send your key in the x-api-key header. That is the only auth step — no token exchange, and no per-endpoint scope to configure.

Header	When	Value
`x-api-key`Required	Every request	Your API key. Header names are case-insensitive, so `X-API-Key` is the same header.
`Authorization`Alternate	Instead of the above	`Bearer <key>` — for clients that only expose bearer auth. Resolves to the same account and the same billing.

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.

Response — GET /v1/routinglookup

Every APIVerve endpoint returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape.

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",
    "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.

Field	Type	Example	Description
`routing_number`	string	`"121000358"`	The ABA routing number for the bank
`office_code`Premium	string	`"O"`	Office code designating the main office or branch location
`record_type_code`Premium	string	`"1"`	Record type code indicating transaction type classification
`new_routing_number`Premium	string	`"000000000"`	New routing number if the bank has been updated
`bank`	string	`"BANK OF AMERICA, N.A."`	Name of the financial institution or bank
`address`Premium	string	`"8001 VILLA PARK DRIVE"`	Street address of the bank's main office location
`city`Premium	string	`"HENRICO"`	City where the bank is located
`state`	string	`"VA"`	Two-letter state abbreviation of bank location
`zip`Premium	string	`"23228"`	Five-digit postal code of bank location
`zip_extension`Premium	string	`"0000"`	Four-digit ZIP code extension for more precise location
`country`	string	`"US"`	Country code (ISO 3166-1 alpha-2 format)
`federal_reserve_district`	string	`"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
`routing_type`	string	`"primary"`	Routing category derived from the routing number prefix: primary, thrift, electronic, government, or travelers_cheque
`is_valid_checksum`	boolean	`true`	Whether the routing number passes the ABA mod-10 checksum
`routing_analysis`Premium	object	`{...}`	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_office`Premium	boolean	`true`
`is_branch`Premium	boolean	`false`
`is_federal_reserve_bank`Premium	boolean	`false`
`is_active`Premium	boolean	`true`
`replaced_by`Premium	object	`null`

Response headers

Every response carries your balance, so your own code always knows where it stands without polling anything. All four are exposed to browsers through CORS.

Header	What it carries
`x-api-remaining-credits`	Credits left in the current cycle
`x-api-credits-used`	Credits spent in the current cycle
`x-api-max-credits`	The allowance for the cycle
`x-api-version`	Version of the endpoint that answered

Errors

Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change.

Status	Meaning	What to do
`400`	Input was rejected	Read `error`; it names the parameter that has to change.
`401`	Key missing or invalid	Check the header name and the key value.
`403`	Key valid, but not permitted here	A key restriction or an IP allow-list — never a bad key.
`429`	Rate limited, or out of credits	Read `error` to tell them apart, then back off or top up.

What a call costs — 10 credits per call

Credits are shared across every APIVerve API — one balance, one key, one bill. Failed requests never count against it, so a rejected input costs nothing.

Plan	Per month	Credits	Routing Number Lookup calls	Per 1,000 calls
Free	Free	200	20	Free
Starter	$29.99	200,000	20,000	$1.50
Pro	$99.99	1,000,000	100,000	$1.00
Mega	$299.99	4,000,000	400,000	$0.75

Calls are what the credits buy at this API's rate — spend them here, on any of the other APIs, or across both. Nothing is reserved per endpoint.

Compare all pricing tiers →

Call it from cURL — GET /v1/routinglookup

No SDK to install — this is a plain HTTPS call to /v1/routinglookup with your key in the x-api-key header. Swap in a real key and it runs as-is.

cURL

1
2

curl "https://api.apiverve.com/v1/routinglookup" \
  -H "x-api-key: YOUR_API_KEY"

Resources

GitHubapiverve/routinglookup-apiSource, issues and the examples this page is built from.ReferenceRouting Number Lookup API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/routinglookupnpm APIVerve.API.RoutingNumberLookupNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Node.js — GET /v1/routinglookup

Install the Node.js SDK, then call the Routing Number Lookup API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.

Install — npm

npm install @apiverve/routinglookup

Node.js

const res = await fetch("https://api.apiverve.com/v1/routinglookup", {
  headers: { "x-api-key": "YOUR_API_KEY" },
});
const { data } = await res.json();
console.log(data);

Resources

npm@apiverve/routinglookupThe published Node.js client, versioned and signed.GitHubapiverve/routinglookup-apiSource, issues and the examples this page is built from.ReferenceRouting Number Lookup API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

APIVerve.API.RoutingNumberLookupNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Python — GET /v1/routinglookup

No SDK to install — this is a plain HTTPS call to /v1/routinglookup with your key in the x-api-key header. Swap in a real key and it runs as-is.

Python

import requests

res = requests.get(
    "https://api.apiverve.com/v1/routinglookup",
    headers={"x-api-key": "YOUR_API_KEY"},
)
print(res.json()["data"])

Resources

Also published for

@apiverve/routinglookupnpm APIVerve.API.RoutingNumberLookupNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from C# / .NET — GET /v1/routinglookup

Install the C# / .NET SDK, then call the Routing Number Lookup API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.

Install — NuGet

dotnet add package APIVerve.API.RoutingNumberLookup

C# / .NET

using var client = new HttpClient();
client.DefaultRequestHeaders.Add("x-api-key", "YOUR_API_KEY");

var json = await client.GetStringAsync("https://api.apiverve.com/v1/routinglookup");
Console.WriteLine(json);

Resources

NuGetAPIVerve.API.RoutingNumberLookupThe published C# / .NET client, versioned and signed.GitHubapiverve/routinglookup-apiSource, issues and the examples this page is built from.ReferenceRouting Number Lookup API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/routinglookupnpm

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Go — GET /v1/routinglookup

No SDK to install — this is a plain HTTPS call to /v1/routinglookup with your key in the x-api-key header. Swap in a real key and it runs as-is.

req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/routinglookup", nil)
req.Header.Set("x-api-key", "YOUR_API_KEY")

res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))

Resources

Also published for

@apiverve/routinglookupnpm APIVerve.API.RoutingNumberLookupNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from PHP — GET /v1/routinglookup

No SDK to install — this is a plain HTTPS call to /v1/routinglookup with your key in the x-api-key header. Swap in a real key and it runs as-is.

PHP

$ch = curl_init("https://api.apiverve.com/v1/routinglookup");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, ["x-api-key: YOUR_API_KEY"]);

$response = curl_exec($ch);
echo $response;

Resources

Also published for

@apiverve/routinglookupnpm APIVerve.API.RoutingNumberLookupNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Ruby — GET /v1/routinglookup

No SDK to install — this is a plain HTTPS call to /v1/routinglookup with your key in the x-api-key header. Swap in a real key and it runs as-is.

Ruby

require "net/http"

uri = URI("https://api.apiverve.com/v1/routinglookup")
req = Net::HTTP::Get.new(uri)
req["x-api-key"] = "YOUR_API_KEY"

res = Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) { |h| h.request(req) }
puts res.body

Resources

Also published for

@apiverve/routinglookupnpm APIVerve.API.RoutingNumberLookupNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Finance

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Routing Number Lookup API

Try it — live request, no key required

About the Routing Number Lookup API

What people use it for

Ways to call it

Other ways to use Routing Number Lookup

Questions.

Request parameters — GET /v1/routinglookup

Required

Authentication

Response — GET /v1/routinglookup

Response fields

Response headers

Errors

What a call costs — 10 credits per call

Call it from cURL — GET /v1/routinglookup

Resources

Also published for

Call it from Node.js — GET /v1/routinglookup

Resources

Also published for

Call it from Python — GET /v1/routinglookup

Resources

Also published for

Call it from C# / .NET — GET /v1/routinglookup

Resources

Also published for

Call it from Go — GET /v1/routinglookup

Resources

Also published for

Call it from PHP — GET /v1/routinglookup

Resources

Also published for

Call it from Ruby — GET /v1/routinglookup

Resources

Also published for

Zero-code embed — one snippet, no backend

Changelog — Routing Number Lookup API

Finance

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