Reply to e-mail mail.message.reply

If you are developing integrations for Bitrix24 using AI tools (Codex, Claude Code, Cursor), connect to the MCP server so that the assistant can utilize the official REST documentation.

Scope: mail

Who can execute the method: a user with access to the mailbox where the e-mail is located

The mail.message.reply method sends a reply to an e-mail.

Method Parameters

Required parameters are marked with *

Name `type`	Description
replyToMessageId* `integer`	The e-mail identifier that needs to be replied to. The identifier can be obtained using the mail.message.list method.
from* `string`	Sender's e-mail. Available addresses can be obtained using the mail.mailbox.senders method.
to* `array`	An array of recipient e-mail addresses
subject* `string`	E-mail subject
body* `string`	E-mail text: plain text or basic HTML
cc `array`	An array of CC recipient e-mail addresses
bcc `array`	An array of BCC recipient e-mail addresses

Code Examples

How to Use Examples in Documentation

The new API call differs by adding the /api/ parameter to the request:

https://{installation_address}/rest/api/{user_id}/{webhook_token}/mail.message.reply

cURL (Webhook)

cURL (OAuth)

PHP

BX24.js

PHP CRest

curl -X POST \
        -H "Content-Type: application/json" \
        -H "Accept: application/json" \
        -d '{"replyToMessageId":15,"from":"user@example.com","to":["client@example.com"],"subject":"Re: Agreement","body":"Thank you, received."}' \
        https://**put_your_bitrix24_address**/rest/api/**put_your_user_id_here**/**put_your_webhook_here**/mail.message.reply

curl -X POST \
        -H "Content-Type: application/json" \
        -H "Accept: application/json" \
        -d '{"replyToMessageId":15,"from":"user@example.com","to":["client@example.com"],"subject":"Re: Agreement","body":"Thank you, received.","auth":"**put_access_token_here**"}' \
        https://**put_your_bitrix24_address**/rest/api/mail.message.reply

SDKs do not yet support the /rest/api/ address in calls. Use direct HTTP requests, for example, via curl, fetch.

try
        {
            const response = await $b24.callMethod(
                'mail.message.reply',
                {
                    replyToMessageId: 15,
                    from: 'user@example.com',
                    to: ['client@example.com'],
                    subject: 'Re: Agreement',
                    body: 'Thank you, received.'
                }
            );
        
            const result = response.getData().result;
            console.log('Success:', result);
        }
        catch( error )
        {
            console.error('Error:', error);
        }

SDKs do not yet support the /rest/api/ address in calls. Use direct HTTP requests, for example, via curl, fetch.

try {
            $response = $b24Service
                ->core
                ->call(
                    'mail.message.reply',
                    [
                        'replyToMessageId' => 15,
                        'from' => 'user@example.com',
                        'to' => ['client@example.com'],
                        'subject' => 'Re: Agreement',
                        'body' => 'Thank you, received.'
                    ]
                );
        
            $result = $response
                ->getResponseData()
                ->getResult();
        
            echo 'Success: ' . print_r($result, true);
        } catch (Throwable $e) {
            error_log($e->getMessage());
            echo 'Error: ' . $e->getMessage();
        }

SDKs do not yet support the /rest/api/ address in calls. Use direct HTTP requests, for example, via curl, fetch.

BX24.callMethod(
            'mail.message.reply',
            {
                replyToMessageId: 15,
                from: 'user@example.com',
                to: ['client@example.com'],
                subject: 'Re: Agreement',
                body: 'Thank you, received.'
            },
            function(result){
                console.info(result.data());
                console.log(result);
            }
        );

SDKs do not yet support the /rest/api/ address in calls. Use direct HTTP requests, for example, via curl, fetch.

require_once('crest.php');
        
        $result = CRest::call(
            'mail.message.reply',
            [
                'replyToMessageId' => 15,
                'from' => 'user@example.com',
                'to' => ['client@example.com'],
                'subject' => 'Re: Agreement',
                'body' => 'Thank you, received.'
            ]
        );
        
        echo '<PRE>';
        print_r($result);
        echo '</PRE>';

Response Handling

HTTP status: 200

{
            "result": {
                "success": true,
                "to": [
                    "client@example.com"
                ]
            },
            "time": {
                "start": 1779819678,
                "finish": 1779819678.84803,
                "duration": 0.8480300903320312,
                "processing": 0,
                "date_start": "2026-05-26T21:21:18+03:00",
                "date_finish": "2026-05-26T21:21:18+03:00",
                "operating_reset_at": 1779820278,
                "operating": 0
            }
        }

Returned Data

Name `type`	Description
result `object`	Object with the sending result
success `boolean`	Success flag
to `array`	Recipients to whom the e-mail was sent
time `time`	Request execution time information

Error Handling

HTTP status: 400

{
            "error": {
                "code": "BITRIX_REST_V3_EXCEPTION_VALIDATION_REQUESTVALIDATIONEXCEPTION",
                "message": "Error during request object validation",
                "validation": [
                    {
                        "message": "Mandatory field is missing",
                        "field": "replyToMessageId"
                    }
                ]
            }
        }

Name `type`	Description
error.code `string`	String error code. Use it to identify the type of exception
error.message `string`	Text description of the error
error.validation `array`	Array with error details. Present only in data validation errors `BITRIX_REST_V3_EXCEPTION_VALIDATION_REQUESTVALIDATIONEXCEPTION`
error.validation[].field `string`	Name of the field where the validation error occurred
error.validation[].message `string`	Description of the error related to the specified field

Possible Error Codes

Request Validation Errors

Error code: BITRIX_REST_V3_EXCEPTION_VALIDATION_REQUESTVALIDATIONEXCEPTION

Field	Error description	How to fix
`replyToMessageId`	Mandatory field is not specified	Pass `replyToMessageId` in the request body
`from`	Mandatory field `from` is not specified	Pass `from` in the request body
`to`	Mandatory field `to` is not specified	Pass `to` in the request body
`subject`	Mandatory field `subject` is not specified	Pass `subject` in the request body
`body`	Mandatory field `body` is not specified	Pass `body` in the request body
`replyToMessageId`	MESSAGE_REPLY_FAILED	Check the existence of the e-mail, access to it, and the correctness of the e-mail data
`to`	NO_RECIPIENTS	Check that the `to` array contains correct recipient addresses
`to`, `cc`, `bcc`	RESOLVE_RECIPIENTS_ERROR	Check the value format and recipient availability in `to`, `cc`, `bcc`

Access Errors

Error code: BITRIX_REST_V3_EXCEPTION_ACCESSDENIEDEXCEPTION

Field	Error description	How to fix
`-`	Access denied	Check user permissions and `mail` scope

Statuses and System Error Codes

HTTP Status: 20x, 40x, 50x

The errors described below may occur when calling any method.

Status	Code Error Message	Description
`500`	`INTERNAL_SERVER_ERROR` Internal server error	An internal server error has occurred. Please contact the server administrator or Bitrix24 technical support
`500`	`ERROR_UNEXPECTED_ANSWER` Server returned an unexpected response	An internal server error has occurred. Please contact the server administrator or Bitrix24 technical support
`503`	`QUERY_LIMIT_EXCEEDED` Too many requests	The request intensity limit has been exceeded
`405`	`ERROR_BATCH_METHOD_NOT_ALLOWED` Method is not allowed for batch usage	The current method is not permitted for calls using batch
`400`	`ERROR_BATCH_LENGTH_EXCEEDED` Max batch length exceeded	The maximum length of parameters passed to the batch method has been exceeded
`401`	`NO_AUTH_FOUND` Wrong authorization data	Invalid access token or webhook code
`400`	`INVALID_REQUEST` Https required	The HTTPS protocol is required for method calls
`503`	`OVERLOAD_LIMIT` REST API is blocked due to overload	The REST API is blocked due to overload. This is a manual individual block; please contact Bitrix24 technical support to lift it
`403`	`ACCESS_DENIED` REST API is available only on commercial plans	The REST API is only available on commercial plans
`403`	`INVALID_CREDENTIALS` Invalid request credentials	The user associated with the access token or webhook used to call the method lacks the necessary permissions
`404`	`ERROR_MANIFEST_IS_NOT_AVAILABLE` Manifest is not available	The manifest is not available
`403`	`insufficient_scope` The request requires higher privileges than provided by the webhook token	The request requires higher privileges than those provided by the webhook token
`401`	`expired_token` The access token provided has expired	The provided access token has expired
`403`	`user_access_error` The user does not have access to the application	The user does not have access to the application. This means that the application is installed, but the portal administrator has restricted access to this application to specific users only
`500`	`PORTAL_DELETED` Portal was deleted	The public part of the site is closed. To open the public part of the site on an on-premise installation, disable the "Temporary closure of the public part of the site" option. Path to the setting: Desktop > Settings > Product Settings > Module Settings > Main Module > Temporary closure of the public part of the site

Continue Learning

Send E-mail

Forward E-mail

Reply to e-mail mail.message.reply

Method ParametersMethod Parameters

Code ExamplesCode Examples

Response HandlingResponse Handling

Returned DataReturned Data

Error HandlingError Handling

Possible Error CodesPossible Error Codes

Request Validation ErrorsRequest Validation Errors

Access ErrorsAccess Errors

Statuses and System Error CodesStatuses and System Error Codes

Continue LearningContinue Learning

Method Parameters

Code Examples

Response Handling

Returned Data

Error Handling

Possible Error Codes

Request Validation Errors

Access Errors

Statuses and System Error Codes

Continue Learning