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Manage a transactional campaign

Article: 000054597
Updated: December 11, 2025

Manage a transactional campaign

Abstract

Describes the request and response details of this Moosend API endpoint to create a transactional campaign.

Post https://{hostname}/v3/campaigns/transactional/send.{format}?apikey=

Sends a transactional campaign to your recipients. You can add content by either creating a campaign inside Moosend and designing the template in the editor (provide the template ID), by providing the HTML body in the API, or by providing a web location.

If a TemplateId is not provided and the TemplateName exists within the platform, the existing campaign will be sent. If the TemplateId is not provided and the TemplateName does not exist within the platform, a new transactional campaign will be created. The payload size provided per API call must be less than 20MB.

Request

Parameter

In

Type

Required

Description

Accept

header

string

true

Determines the expected format and data type to retrieve the response data.

Value: application/json

apikey

query

string

true

The API key of your account.

From

body

object

false

An array containing the parameters of the sender:

Email - the email address of a verified sender.

sendersName - the name of the sender name displayed in the recipient's inbox.

ReplyTo

body

object

false

An array containing the parameters of the sender the user can reply to:

Email - the email address of one of a verified sender.

sendersName - the name of the Reply to email displayed to the user when the user clicks Reply.

Subject

body

string

false

The subject line of the email message displayed to the recipient. It may contain parameters for personalization. When no value is provided, use the subject of the template.

Cc

body

array

false

An array of email addresses to include as carbon copy (Cc) recipients of the message.

Bcc

body

array

false

An array of email addresses to include as blind carbon copy (Bcc) recipients of the message.

TemplateId

body

GUID

false

Statistics will be registered to the campaign with this ID. If you have created a template id, you can find it in the user interface.

If the array content is empty or doesn’t exist, then the content for the email is taken from the template id provided.

TemplateName

body

string

false

The name of the transactional campaign that this message will be sent for. Transactional campaign names are unique.

If the array content is empty or doesn’t exist, then the content for the email is taken from the template name provided.

Content

body

array

false

Content types:

Type - the type of content to send.

Value - the format specified by content.type. It may contain parameters to be substituted for each recipient, according to the parameters given in the personalization property.

WebLocation - the URL that holds the content to use for this message. To reuse it for the next requests and avoid re-downloading, cache it to S3 for 24 hours.

Only one content should exist in the payload for the call to be valid. If there is a content and template ID or name, then the content overrules and the template ID is kept to show the location of the statistics. Current limit is 1MB.

Personalizations

body

array

true

A list of recipients of the transactional message. It may contain personalization parameters.

To - an array containing the parameters of the receiver

Email - the recipient email address (text/plain).

Name - the recipient name (text/plain).

Cc - an array of email addresses to include as carbon copy (Cc) recipients of the message.

Bcc - an array of email addresses to include as blind carbon copy (Bcc) recipients of the message.

Substitutions - the values to substitute in the message content/subject for the current recipient, in the form of key/value pairs. There are some restricted keywords implemented, see note below.

MailSettings

body

array

true

BypassUnsubscribeManagement

When set to true or omitted, the message will be delivered to the recipient, even if they have unsubscribed from the transactional email list.

Default: true

IncludeUnsubscribeLink

Let's you turn the unsubscribe link on or off or provide a website link to use instead; this will temporarily override the saved settings without changing them.

Default: false

ScheduledForDatetime

When omitted, the transactional campaign will be dispatched immediately. If the value exists in the format “YYYY-MM-DD“ or “YYYY-MM-DDThh:mm:ss“ then the campaign will be scheduled for that time. Scheduled time cannot be in the past.

Default null

ScheduledForTimezone

When omitted, the system will take the time zone from the user’s settings if present, otherwise will default to “UTC“ . If given in the request, it will be validated against the list of valid IANA or Windows time zones (both valid).

Default null

attachments

body

object

false

An array containing the parameters of the attachments: -

Content - A base64 string that represents the file bytes of the attachment (Required).

Type - The MIME type of the attached content (e.g. application/pdf, image/PNG) (Required).

FileName - The file name of the attachment that the recipient will see (Required).

Disposition - Allowed values are: “inline”, “attachment” (Required).

ContentId - A user-defined string that maps an embedded image to an attachment. (Required only for inline disposition).

Note

Restricted keywords for substitutions: datetime, ab, appDomain, appDomainProtocol, trackingDomain, doubleOptInDomain, utilitiesDomain, updatePreferences, emailSentTo, forwardToFriendLink, updateProfileLink, verificationLink, unsubscribeLink.

Response

Status

Description

Headers

Schema

200 OK

The request is successful.

Content-Type:application/json

Accept:application/json

N/A

 

POST https://{hostname}/v3/campaigns/transactional/send.{format}?apikey=

 Request body: {
    "userId": "075de68e-fcdf-408e-89e4-72f7932e9cdb",
    "replyto": {
        "email": "lauren.doe@example.com",
        "name": "lauren"
    },
    "templateid": "6e3d31b7-418a-466f-9b22-c33a8de3ec93",
    "MailSettings": { 
        "BypassUnsubscribeManagement": { 
            "Enable": true 
        },
        "UnsubscribeLinkManagement": { 
            "IncludeUnsubscribeLink": false 
        },
        "ScheduledForDatetime": "2025-10-24T18:38:00",
        "ScheduledForTimezone": "UTC"
    },
    "personalizations": [
        {
            "to": [
                {
                    "Name": "test_name_exampledoe",
                    "Email": "peta+doe@example.net"
                }
            ],
            "Substitutions": {
                "order": {
                    "products": [
                        {
                            "name": "product 1",
                            "link": "https://google.com",
                            "price": {
                                "grossValue": 12,
                                "netValue": 10
                            },
                            "details": [
                                "tech",
                                "deals"
                            ],
                            "img": "https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRkMUT64OeYHqrGNF0ss-8tVMaaRBVRqWfL6w&s"
                        },
                        {
                            "name": "product 2",
                            "link": "https://moosend.com",
                            "price": {
                                "grossValue": 6,
                                "netValue": 5
                            },
                            "details": [
                                "tech",
                                "deals"
                            ],
                            "img": "https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRkMUT64OeYHqrGNF0ss-8tVMaaRBVRqWfL6w&s"
                        }
                    ]
                }
            },
            "CustomArguments": 
            { 
                "TestKey": "TestValue"
            } 
        },
        {
            "to": [
                {
                    "Name": "test_name_peta",
                    "Email": "peta+1@example.net"
                }
            ],
            "Substitutions": {
                "order": {
                    "products": [
                        {
                            "name": "product 1",
                            "link": "https://google.com",
                            "price": {
                                "grossValue": 12,
                                "netValue": 10
                            },
                            "details": [
                                "tech",
                                "deals"
                            ],
                            "img": "https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRkMUT64OeYHqrGNF0ss-8tVMaaRBVRqWfL6w&s"
                        },
                        {
                            "name": "product 2",
                            "link": "https://moosend.com",
                            "price": {
                                "grossValue": 6,
                                "netValue": 5
                            },
                            "details": [
                                "tech",
                                "deals"
                            ],
                            "img": "https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRkMUT64OeYHqrGNF0ss-8tVMaaRBVRqWfL6w&s"
                        }
                    ]
                }
            },
            "CustomArguments": 
            { 
                "TestKey": "TestValue2"
            } 
        }
    ]
}
 


curl --location 'https://{hostname}/v3/campaigns/transactional/send.{format}?apikey=' \
--header 'Content-Type: application/json' \
--data-raw 'POST https: 
 Request body: {
    "userId": "075de68e-fcdf-408e-89e4-72f7932e9cdb",
    "replyto": {
        "email": "lauren.doe@example.com",
        "name": "lauren"
    },
    "templateid": "6e3d31b7-418a-466f-9b22-c33a8de3ec93",
    "MailSettings": {
        "BypassUnsubscribeManagement": {
            "Enable": true
        },
        "UnsubscribeLinkManagement": {
            "IncludeUnsubscribeLink": false
        },
        "ScheduledForDatetime": "2025-10-24T18:38:00",
        "ScheduledForTimezone": "UTC"
    },
    "personalizations": [
        {
            "to": [
                {
                    "Name": "test_name_exampledoe",
                    "Email": "peta+doe@example.net"
                }
            ],
            "Substitutions": {
                "order": {
                    "products": [
                        {
                            "name": "product 1",
                            "link": "https://google.com",
                            "price": {
                                "grossValue": 12,
                                "netValue": 10
                            },
                            "details": [
                                "tech",
                                "deals"
                            ],
                            "img": "https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRkMUT64OeYHqrGNF0ss-8tVMaaRBVRqWfL6w&s"
                        },
                        {
                            "name": "product 2",
                            "link": "https://moosend.com",
                            "price": {
                                "grossValue": 6,
                                "netValue": 5
                            },
                            "details": [
                                "tech",
                                "deals"
                            ],
                            "img": "https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRkMUT64OeYHqrGNF0ss-8tVMaaRBVRqWfL6w&s"
                        }
                    ]
                }
            },
            "CustomArguments": {
                "TestKey": "TestValue"
            }
        },
        {
            "to": [
                {
                    "Name": "test_name_peta",
                    "Email": "peta+1@example.net"
                }
            ],
            "Substitutions": {
                "order": {
                    "products": [
                        {
                            "name": "product 1",
                            "link": "https://google.com",
                            "price": {
                                "grossValue": 12,
                                "netValue": 10
                            },
                            "details": [
                                "tech",
                                "deals"
                            ],
                            "img": "https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRkMUT64OeYHqrGNF0ss-8tVMaaRBVRqWfL6w&s"
                        },
                        {
                            "name": "product 2",
                            "link": "https://moosend.com",
                            "price": {
                                "grossValue": 6,
                                "netValue": 5
                            },
                            "details": [
                                "tech",
                                "deals"
                            ],
                            "img": "https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRkMUT64OeYHqrGNF0ss-8tVMaaRBVRqWfL6w&s"
                        }
                    ]
                }
            },
            "CustomArguments": {
                "TestKey": "TestValue2"
            }
        }
    ]
}'
Response
json
{
  "TotalAccepted": 1,
  "TotalExcluded": 1,
  "ExcludedRecipients": [
    {
      "Email": "recipient@domain.dom",
      "Reason": "The recipient was found with status bounced"
    }
  ]
}

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