# invalid_phone_number

- HTTP status: 400
- Retry: No
- Execution: not started
- Admin needed: no

**Invalid phone number.** Phone numbers must be E.164 strings: a `+`, the country code and the subscriber number, digits only, at most 15 digits (for example `+919000000001`).

## What it means

The API returns HTTP 400 with `error.code` set to `invalid_phone_number`. The default message is: "The phone number is not a valid E.164 number."

## Common causes

- A local format such as `09000000001` or `(202) 555-0100`.
- Spaces, dashes or letters in the number.
- A number too short or too long for E.164.

## How to identify it

Check the response status (`400`) and `error.code` (`invalid_phone_number`). Branch on `error.code`, not on the message text: messages can be reworded, codes do not change within v1. Log `error.request_id` (also sent as the `X-Request-Id` header) so support can find the request.

## How to fix it

- Normalize numbers to E.164 before sending them.

## Retry guidance

Sending the request unchanged fails the same way. Fix the cause first (see How to fix it), then send it again.

## Did anything happen?

This request was refused before any call was placed and before anything was charged.

## Idempotency

Nothing was done. Fix the request and send it again; if you sent an Idempotency-Key you may reuse it, because a refused request is not stored.

## Who can fix it

The developer who sends the request can fix it; no administrator action is normally needed.

## When to contact support

If the error persists after the steps above, contact [support@relationsai.com](mailto:support@relationsai.com). See [Support](/resources/support) for what to include (the `request_id`, the time in UTC, the operation, and whether you used a test or live key) and what never to send (API keys, Authorization headers, webhook signing secrets, recording links, transcripts or customer data).

## Example error response

```json
{
  "error": {
    "code": "invalid_phone_number",
    "message": "The phone number is not a valid E.164 number.",
    "details": {
      "field": "to"
    },
    "request_id": "req_m3wrr5j6pwetgyu2pu4iwkmm",
    "retry": "no",
    "doc_url": "https://docs.relationsai.com/errors/invalid_phone_number"
  }
}
```

## Incorrect and corrected request

Incorrect: A local format with a leading zero and no country code.

```http
POST /v1/calls
Authorization: Bearer rai_test_YOUR_TEST_KEY
Content-Type: application/json

{
  "agent_id": "agent_4Nf8Gt2Hx6Jq9Lm3Pv7Rs1",
  "to": "09000000001"
}
```

Corrected: The same number in E.164: `+`, the country code, then the subscriber number.

```http
POST /v1/calls
Authorization: Bearer rai_test_YOUR_TEST_KEY
Content-Type: application/json

{
  "agent_id": "agent_4Nf8Gt2Hx6Jq9Lm3Pv7Rs1",
  "to": "+919000000001"
}
```

## Operations that can return this error

- [`POST /calls`](/api/calls#place-a-call): Place a call
- [`POST /contacts`](/api/contacts#create-a-contact): Create a contact
- [`POST /contacts/upsert`](/api/contacts#create-or-update-a-contact-by-phone-number): Create or update a contact by phone number
- [`PATCH /contacts/{contact_id}`](/api/contacts#update-a-contact): Update a contact
- [`POST /dnc-entries`](/api/do-not-call-list#add-a-number-to-the-do-not-call-list): Add a number to the do-not-call list
- [`GET /dnc-entries`](/api/do-not-call-list#list-or-look-up-do-not-call-entries): List or look up do-not-call entries
- [`GET /contacts`](/api/contacts#list-contacts): List contacts
- [`GET /calls`](/api/calls#list-calls): List calls

See all codes in the [error-code reference](/fundamentals/error-codes).