--- title: "Collect newsletter subscribers (Opt-In)" description: Ultimate Membership Pro can add every new member to your mailing list in Mailchimp, ActiveCampaign, AWeber, GetResponse and other services, with an optional consent checkbox on the registration form. url: "https://ultimatemembershippro.com/docs/how-to-activate-optin-subscriptions/" updated: "2026-10-18" category: "Emails & Notifications" tags: - email - OptIn - subscribers - subscription --- # Collect newsletter subscribers (Opt-In) 6 minBeginnerUltimate Membership Pro 14.2+ In Ultimate Membership Pro, Opt-In sends the email address of each new member to [your mailing list](https://ultimatemembershippro.com/integrations/email-marketing/), so your newsletter grows with your membership. It works with Mailchimp, ActiveCampaign, AWeber, GetResponse, Campaign Monitor, Constant Contact, iContact, Mad Mimi, Mailster and Wysija, or keeps a simple list on your site. This guide connects a service, turns Opt-In on for the registration form and adds a consent checkbox so members choose whether to join. Before you start - An account with your email marketing service and a list (audience) for new members. Check that the list accepts contacts with only an email address and name, without extra required fields. - The registration form is set up. See [Set up the registration form](https://ultimatemembershippro.com/docs/set-up-the-registration-form/). ## Enter your service's details 1. Go to Ultimate Membership Pro*›*Modules and open **Opt-In Management** (in the Notifications & Marketing group). It's always available; there is nothing to switch on. 2. Find the box of your service, fill in its details and click its own Save Changes button. [![Mailchimp box with API Key and ID List filled in and the Save Changes button](https://ultimatemembershippro.com/wp-content/uploads/2026/10/ump-opt-in-01-mailchimp.png)](https://ultimatemembershippro.com/wp-content/uploads/2026/10/ump-opt-in-01-mailchimp.png) Mailchimp needs two values; the links under the fields show where to find them. Active Campaign **Api URL**, **Api Key:** and **List ID:** from your ActiveCampaign account settings. Aweber Paste the **Auth Code** from the **Get Your Auth Code From Here** link, enter the **Unique List ID** and click Connect. Mailchimp **API Key** and **ID List** ([the audience ID](https://mailchimp.com/help/find-audience-id/)). Members are added as subscribed, without a Mailchimp confirmation email. Get Response **API Key** and **List token**. Campaign Monitor **API Key** and **List ID**. IContact **Username**, **App ID**, **App Password** and the list ID. Constant Contact **Client Id** and **Client Secret** of an app you create at Constant Contact, then Authenticate and pick the **List**. The box lists the steps and the Redirect URI to use. Wysija Contact **Select Wysija List:** lists the lists of the Wysija (MailPoet) plugin on your site. Mailster (MyMail) **Select MyMail List:** lists the lists of the Mailster plugin on your site. Mad Mimi **Username Or Email:**, **Api Key:** and **List Name:**. E-mail List No service: addresses are stored on your site and shown in **Saved E-mail List** at the bottom of the screen, separated by commas, ready to copy. ## Turn on Opt-In for the registration form 1. Go to Ultimate Membership Pro*›*Registration Form, tab **Register Form Showcase**. 2. Switch on **Opt-In Subscription**. 3. Under **Choose Opt-In Service**, click the service you set up in step 1. 4. Click Save Changes. [![Opt-In Subscription switched on with the Choose Opt-In Service grid; MailChimp is selected](https://ultimatemembershippro.com/wp-content/uploads/2026/10/ump-opt-in-02-register.png)](https://ultimatemembershippro.com/wp-content/uploads/2026/10/ump-opt-in-02-register.png) One service receives the new members. 1Opt-In Subscription Sends each new member to the chosen service when they register. Default: **Off** 2Choose Opt-In Service The destination: one of the 11 options. Only one service is used at a time. ## Ask for consent with a checkbox Without a checkbox, every new member is added to your list. To let members choose, show the opt-in field on the form: 1. In Ultimate Membership Pro*›*Registration Form, open the **Custom Fields** tab. 2. Find the field `ihc_optin_accept` (label “I would like to subscribe to newsletter list” by default) and switch on **On Registration**. 3. Optional: edit the field to change the label, or switch on **Input Checkbox checked by default** under Default State. 4. Click Save Changes. [![Registration form checkbox labelled Email me weekly coaching tips](https://ultimatemembershippro.com/wp-content/uploads/2026/10/ump-opt-in-03-checkbox.png)](https://ultimatemembershippro.com/wp-content/uploads/2026/10/ump-opt-in-03-checkbox.png) The checkbox with a custom label. With the field on the form, only members who tick it are sent to your list. ## When a member is added Main registration form Right after the account is created, with the email address, first name and last name. With Double Email Verification After the member clicks the confirmation link, not before. See [Verify members’ email addresses](https://ultimatemembershippro.com/docs/how-to-activate-double-email-verification/). Register Lite form When **Enable Opt-In** is on in the Register Lite module. It uses the service chosen on the Registration Form and has no consent checkbox. See [Registration with email only](https://ultimatemembershippro.com/docs/register-light/). Good to know - Only new registrations are sent. Members who registered before you turned Opt-In on, and members you add in the admin, are not added to the list. - Changes members make later in their profile (a new email address, unticking the checkbox) are not synced to the service. - If your list asks for extra required fields or its own double opt-in, the service may refuse or hold the contact. Start with a plain list. ## Example: Coaching Club newsletter **Weekly coaching tips**New members who tick the box join the Mailchimp audience for the weekly tips email. **Service** : Mailchimp **API Key** : Your Mailchimp API key **ID List** : The audience ID, for example a1b2c3d4e5 **Opt-In Subscription** : On **Choose Opt-In Service** : MailChimp **ihc_optin_accept field** : On Registration, label “Email me weekly coaching tips” ## Troubleshooting Why are new members not added to my list? Check, in order: the service details on the Opt-In Management screen (and that you saved that box); that Opt-In Subscription is on and the right service is chosen on the Registration Form; that the member ticked the opt-in checkbox, if it's on the form; and, with Double Email Verification, that the member confirmed the email. Then check the list itself for required fields or a double opt-in setting, or try a new, plain list. Does Opt-In send anything besides the email address? It sends the email address and, when the form has them, the first and last name. Custom fields are not sent. Can I send members to different lists by Membership? Not with the built-in Opt-In: all new members go to the one service and list you chose. Where do I see the addresses collected with E-mail List? At the bottom of the Opt-In Management screen, in Saved E-mail List, separated by commas. ## What's next [**Set up the registration form**Fields and settings of the sign-up form.](https://ultimatemembershippro.com/docs/set-up-the-registration-form/)[**Add custom fields to the registration form**Edit the opt-in checkbox and other fields.](https://ultimatemembershippro.com/docs/add-custom-fields/)[**Set up email notifications**The emails the plugin sends itself.](https://ultimatemembershippro.com/docs/how-to-send-notifications/)[**Verify members' email addresses**Confirm addresses before they join your list.](https://ultimatemembershippro.com/docs/how-to-activate-double-email-verification/)