API · Create · Entities
Check name availability.
Validate a proposed company name against a jurisdiction's naming rules before you file. Runs the state's entity-name ruleset — required entity-type designator (Inc., LLC, …), reserved words, and restricted terms — and flags collisions with names already in your Matter workspace, both exact and deceptively-similar (phonetic).
This is a pre-filing check, not an authoritative registry clearance: the state's own index is the source of truth, and final availability is confirmed when the formation is filed. Use it to steer a name picker early, then rely on the filing's own name check to confirm.
Returns available: true | false, the normalized form of the name, any near-matches that triggered a conflict, and (optionally) suggested variants. Safe to call from the browser with a pk_live_ publishable key.
Coverage: Delaware today; additional jurisdictions rolling out.
Last updated
Query Parameters
namestringRequiredProposed legal name including the entity-type suffix (e.g. Acme Labs, Inc.).
jurisdictionstringRequiredISO 3166-2 subdivision code. For US entities, this is the formation state
(US-DE, US-CA). For entities in other countries, top-level jurisdiction code.
include_similarbooleanOptionalInclude similarly-named entities in the response.
Response Body
application/json
application/problem+json
application/problem+json
application/problem+json
Request
curl -X GET "https://api.mattermode.com/v1/entities/name_availability?name=string&jurisdiction=US-DE"fetch("https://api.mattermode.com/v1/entities/name_availability?name=string&jurisdiction=US-DE", { method: "GET"})package mainimport ( "fmt" "net/http" "io/ioutil")func main() { url := "https://api.mattermode.com/v1/entities/name_availability?name=string&jurisdiction=US-DE" req, _ := http.NewRequest("GET", url, nil) res, _ := http.DefaultClient.Do(req) defer res.Body.Close() body, _ := ioutil.ReadAll(res.Body) fmt.Println(res) fmt.Println(string(body))}import requestsheaders = { "Authorization": "Bearer sk_test_4eC39HqLyjWDarjtT1zdp7dc", "Matter-Version": "2026-06-10",}resp = requests.get( "https://api.mattermode.com/v1/entities/name_availability", headers=headers,)resp.raise_for_status()print(resp.json())import java.net.URI;import java.net.http.HttpClient;import java.net.http.HttpRequest;import java.net.http.HttpResponse;import java.net.http.HttpResponse.BodyHandlers;import java.time.Duration;HttpClient client = HttpClient.newBuilder() .connectTimeout(Duration.ofSeconds(10)) .build();HttpRequest.Builder requestBuilder = HttpRequest.newBuilder() .uri(URI.create("https://api.mattermode.com/v1/entities/name_availability?name=string&jurisdiction=US-DE")) .GET() .build();try { HttpResponse<String> response = client.send(requestBuilder.build(), BodyHandlers.ofString()); System.out.println("Status code: " + response.statusCode()); System.out.println("Response body: " + response.body());} catch (Exception e) { e.printStackTrace();}using System;using System.Net.Http;using System.Text;var client = new HttpClient();var response = await client.GetAsync("https://api.mattermode.com/v1/entities/name_availability?name=string&jurisdiction=US-DE");var responseBody = await response.Content.ReadAsStringAsync();curl --request GET 'https://api.mattermode.com/v1/entities/name_availability' \ --header 'Authorization: Bearer sk_test_4eC39HqLyjWDarjtT1zdp7dc' \ --header 'Matter-Version: 2026-06-10'const response = await fetch("https://api.mattermode.com/v1/entities/name_availability", { method: "GET", headers: { "Authorization": "Bearer sk_test_4eC39HqLyjWDarjtT1zdp7dc", "Matter-Version": "2026-06-10", },});if (!response.ok) { throw new Error(`Matter API ${response.status}: ${await response.text()}`);}const data = await response.json();console.log(data);Response
application/json{
"available": false,
"name": "Waypoint Systems, Inc.",
"normalized_name": "string",
"jurisdiction": "US-DE",
"reasons": [
"string"
],
"similar_matches": [
{
"status": "active"
}
],
"suggested_variants": [
"string"
]
}{
"type": "https://mattermode.com/docs/errors/invalid_request",
"title": "Invalid request",
"status": 400,
"code": "invalid_request",
"detail": "Request body could not be parsed as JSON.",
"doc_url": "https://mattermode.com/docs/guides/errors#invalid_request",
"request_id": "req_Qw9xYz8A"
}{
"type": "https://mattermode.com/docs/errors/authentication_required",
"title": "Authentication required",
"status": 401,
"code": "authentication_required",
"detail": "No bearer token was supplied. Pass `Authorization: Bearer sk_live_...` on every request.",
"doc_url": "https://mattermode.com/docs/guides/errors#authentication_required",
"request_id": "req_Qw9xYz8A"
}{
"type": "https://mattermode.com/docs/errors/rate_limit_exceeded",
"title": "Rate limit exceeded",
"status": 429,
"code": "rate_limit_exceeded",
"detail": "Request rate exceeded for this key. Retry after `retry_after` seconds or honor the `Retry-After` header.",
"doc_url": "https://mattermode.com/docs/guides/errors#rate_limit_exceeded",
"request_id": "req_Qw9xYz8A",
"retry_after": 30
}