Subscribe To Constant Contact

Audience: Low-code Engineers

Skill Prerequisites: Actions, Forms, Constant Contact account

Adds the email address from a form field to a Constant Contact list. You can also send the contact's name, company, phone numbers, address and custom fields from other form fields. If the contact already exists, it's updated and the list is added to its lists.

note

This action is part of the Constant Contact add-on (ActionForm.ConstantContact). The add-on is installed separately and is licensed with the CONSTANTC feature, but the action doesn't check the license when it runs. If you don't see the action in the Email group, the add-on isn't installed. See Constant Contact.

caution

The action uses Constant Contact's old V2 API (api.constantcontact.com/v2). Constant Contact no longer issues V2 API keys and recommends the V3 API, which this action doesn't support. You can only use it if you already have a V2 API key and access token, and it stops working when Constant Contact turns off the V2 API. For new work, call the V3 API with Server Request instead.

Typical Use Cases

• Add newsletter sign-ups from a form to a Constant Contact list
• Add a contact's name, company and address to Constant Contact when they register

Don't use it to

• Subscribe someone from a workflow, an API endpoint or a scheduled job. The action only works when a form is submitted.
• Remove someone from a list. Use Unsubscribe from Constant Contact instead.
• Import large lists. Each run sends one address.

Related Actions

Action Name	Description
Unsubscribe from Constant Contact	Removes an email address from one Constant Contact list.
Subscribe to Mailchimp	Adds an email address to a Mailchimp audience.
Server Request	Calls the Constant Contact V3 API, which this action doesn't support.

Input Parameter Reference

Parameter	Description	Supports Tokens	Default	Required
API Key	The V2 API key of your Constant Contact developer account. Type the key itself. A token isn't replaced.	No	empty string	Yes
Token	The V2 access token for your Constant Contact account. It's sent as a bearer token. Type the token itself. A token such as [CCToken] isn't replaced.	No	empty string	Yes
List Name	The name of the list, exactly as it appears in Constant Contact under Contacts, including capitals.	No	empty string	Yes
Email Field	The email field on the form with the address to subscribe.	No	none selected	Yes
List Data	Rows that copy form values to the contact. In Action Form Field ID, enter the name of a form field, for example FirstName. In ConstantContact Name, enter one of the names in Contact fields.	No	empty	No

Output Parameters Reference

The action has no output parameters.

Contact fields

The ConstantContact Name column of List Data takes these names:

Name	Contact field
FNAME, MNAME, LNAME	First, middle and last name.
CNAME, JTITLE	Company name and job title.
CPHONE, WPHONE, HPHONE, FAX	Cell, work and home phone, and fax.
ADDR1, ADDR2, ADDR3, CITY, PCODE	Address lines, city and postal code.
COUNTRY	The country code, for example US.
ADDRTYPE	PERSONAL or BUSINESS, in any case. Any other value, or no value, gives PERSONAL.

• Names are case-sensitive. Other names are ignored.
• Use each name only once. Two rows with the same name make the action fail.
• If the form field is empty, the contact field is sent with no value.

Custom fields

The action also sends Constant Contact custom fields. You don't map them in List Data. The action looks for them by name:

• Form fields or tokens named CustomField1 to CustomField15 are sent as the custom fields with those names. Empty values are skipped.
• A form field or token named HiddenCustomFields can hold more, as Name:Value pairs separated by semicolons, for example CustomField3:Gold;CustomField4:2026. Use it to send custom fields with values you set yourself, for example from a hidden field.

Things to know:

• Numbering starts at 1. The action's help text says CustomField0, but the action never reads CustomField0.
• HiddenCustomFields stops at the first bad pair. A pair without : and everything after it is ignored, without an error. A value that contains : is cut at that :.
• At most 15. More than 15 custom fields in total make the action fail.

What happens when it fails

The action stops execution and the form shows an error in these cases:

Message	When
This service is not configured properly	API Key, Token or List Name is empty. The visitor sees a general "Something went wrong" message, and this text is in the log.
The email address is invalid	The email field is empty. As above, this text is in the log.
This email address is already registered	Constant Contact's error contains this text.
Something went wrong during the registration	Any other problem. This includes a list name that doesn't exist, a wrong key or token, more than 15 custom fields, a V2 API that no longer answers, and running the action outside a form.

Most problems give Something went wrong during the registration. The message doesn't include the Constant Contact error.

Considerations

• Only in forms. The action reads the mapped values and custom fields from the submitted form. In a workflow, an API endpoint or a scheduled job, it always fails with Something went wrong during the registration.
• Existing contacts. If the address is already a contact, the action keeps its lists, adds this list and updates the contact. Unmapped and empty contact fields are sent with no value. Check in Constant Contact whether an update clears values the contact already had.
• Not confirmed. Contacts are added as not confirmed, and the action is marked as done by the visitor (ACTION_BY_VISITOR).
• Keys in plain text. The API key and token aren't tokenized, so you type them into the action and they're saved with the form. Anyone who can edit the form can read them.
• API key in the URL. The API key is sent in the query string of every request, so it can show up in proxy and web server logs, and in the details of failed requests.
• Consent. The action subscribes whatever address is in the field. Make sure your form asks for consent as your local email laws require.

Examples

tip

To understand how to use the below examples, please see Running Examples.

1. Subscribe a form sign-up with name and company

Add this action to the submit button of a form with Email, FirstName, LastName and Company fields. It subscribes the address in Email to the Newsletter list and sends the name and company. Replace the API key and token with your own.

{
    "Title": "Subscribe To Constant Contact",
    "ActionType": "SubscribeToConstantContact",
    "Description": "Add the sign-up to the newsletter list",
    "Parameters": {
        "ApiKey": "your-v2-api-key",
        "Token": "your-v2-access-token",
        "ListName": "Newsletter",
        "EmailField": "Email",
        "Data": {
            "FirstName": "FNAME",
            "LastName": "LNAME",
            "Company": "CNAME"
        }
    }
}

To send a custom field as well, add a field named CustomField1 to the form. Its value is sent as the CustomField1 custom field.

Revised 10/03/2026