Skip to main content
The Company Name Checker API lets you verify whether a proposed business name is already in use across one or more US jurisdictions. Use it before starting an incorporation to reduce the chance of a name rejection.

​
How it works

You submit a company name along with one or more jurisdictions (US states). The API searches public business registries for exact matches and returns availability per jurisdiction. A name is considered unavailable if an existing registered company in the same state has a legal or trading name that matches your query after normalization (lowercased, non-alphanumeric characters removed).

​
Authentication

Pass your API key in the x-api-key header on every request. Contact the Commenda team if you do not have a key. 
curl --request POST \
  --url 'https://api.prod.commenda.io/api/v1/company-name-checker' \
  --header 'x-api-key: <your_api_key>' \
  --header 'Content-Type: application/json' \
  --data '{
    "name": "Acme Corp",
    "jurisdictions": [
      { "level": "STATE_OR_PROVINCE", "country": "US", "code": "DE" },
      { "level": "STATE_OR_PROVINCE", "country": "US", "code": "CA" }
    ]
  }'

​
Request body

FieldTypeRequiredDescription
namestringYesThe proposed company name to check.
jurisdictionsarrayYesOne or more jurisdictions to check against.
jurisdictions[].levelstringYesJurisdiction level. Currently only STATE_OR_PROVINCE is supported.
jurisdictions[].countrystringYesISO country code. Currently only US is supported.
jurisdictions[].codestringYesTwo-letter state or province code (for example, DE, CA, NY).

​
Response

A successful response returns the proposed name and an availability entry for each requested jurisdiction. 
{
  "name": "Acme Corp",
  "availability": [
    {
      "level": "STATE_OR_PROVINCE",
      "country": "US",
      "code": "DE",
      "available": true,
      "success": true,
      "error": ""
    },
    {
      "level": "STATE_OR_PROVINCE",
      "country": "US",
      "code": "CA",
      "available": false,
      "success": true,
      "error": ""
    }
  ]
}
FieldTypeDescription
namestringThe company name that was checked.
availability[].levelstringThe jurisdiction level that was checked.
availability[].countrystringThe country code.
availability[].codestringThe state or province code.
availability[].availablebooleantrue if no exact match was found in the jurisdiction.
availability[].successbooleantrue if the check completed without errors.
availability[].errorstringError message if the check failed, empty string otherwise.

​
Supported jurisdictions

The API currently supports all 50 US states plus the District of Columbia and Puerto Rico.

​
Error handling

If the API cannot complete the check, each jurisdiction entry in the response will have success set to false and the error field will contain a description. Common errors:
ErrorCause
Country not supportedA country other than US was provided.
Jurisdiction code not supportedAn invalid state code was provided for the given country.
Missing or invalid x-api-keyThe request did not include a valid API key.

​
When to use this API

  • Before starting an incorporation — check your preferred name and alternatives across target states.
  • Bulk name validation — submit multiple jurisdictions in a single request to check availability in parallel.
  • Automated workflows — integrate the check into your onboarding or entity-creation flow to catch conflicts early.
Name availability results are based on publicly available registry data and may not reflect very recent filings. Treat results as a strong indicator rather than a legal guarantee.