MailerLite

MailerLite is an email marketing platform for managing subscribers, groups, segments, campaigns, and automations. This connector uses the MailerLite REST API to read account objects such as subscribers, segments, campaigns, and forms, and to write records back to MailerLite to create and update subscribers, groups, custom fields, campaigns, and webhooks.

Power end-to-end data operations for your MailerLite API with Nexla. Our bi-directional MailerLite connector is purpose-built for MailerLite, making it simple to ingest data, sync it across systems, and deliver it anywhere — all with no coding required. Nexla turns API-sourced data into ready-to-use, reusable data products and makes it easy to send data to MailerLite or any other destination. With comprehensive monitoring, lineage tracking, and access controls, Nexla keeps your MailerLite workflows fast, secure, and fully governed.

Features

Type: API

SourceDestination

• Seamless API Integration: Connect to any endpoint as source or destination without coding, with automatic data product creation
• Visual Composition & Chaining: Build complex integrations using visual templates, chain API calls, and compose workflows with data validation and filtering
• API Proxy: Expose curated slices of your data securely with a secure and customizable API proxy that validates and transforms data on the fly
• Request optimization with intelligent batching, retry, and caching to minimize API calls and costs

Prerequisites

Before creating a MailerLite credential, you need a MailerLite API key. MailerLite authenticates every API request with a Bearer token sent in the Authorization header, and all requests are made against the base URL https://connect.mailerlite.com/api.

To obtain your MailerLite API key, follow these steps:

1. Sign in to your MailerLite account.

2. Open Integrations, then select MailerLite API.

3. Click Generate new token and enter a descriptive name to identify the token (for example, "Nexla Integration").

4. Copy the generated API key immediately and store it securely. MailerLite does not retain keys in plain text and will not display the key again after you leave the page.

The API key is sent as Authorization: Bearer <your-api-key> on every request. If your key is compromised, revoke it in the MailerLite API integration settings and generate a new one. For details on authentication, endpoints, and response formats, see the MailerLite API Documentation.

Authenticate

Credentials required

Authenticate using MailerLite API key in the Authorization header with Bearer token scheme.

Field	Required	Secret	Description
API Key	Yes	Yes	Your MailerLite API key for authentication.
Base URL	Yes	No	The base URL for the MailerLite API.

Create a credential in Nexla

1. After selecting the data source/destination type, click the Add Credential tile to open the Add New Credential overlay.

2. Enter a name for the credential in the Credential Name field and a short, meaningful description in the Credential Description field.

3. Enter your MailerLite API key in the API Key field. This is the token you generated in Prerequisites and is sent in the Authorization header as a Bearer token.

4. Confirm the Base URL field. It defaults to https://connect.mailerlite.com/api, which is correct for standard MailerLite accounts.

   The API key grants access to your MailerLite account data and should be treated as sensitive information. If it is compromised, revoke it in the MailerLite API integration settings and generate a new one.

   For detailed information about MailerLite API authentication and available endpoints, see the MailerLite API Documentation.

5. Click the Save button at the bottom of the overlay. The newly added credential will now appear in a tile on the Authenticate screen during data source/destination creation.

Use as a data source

To create a new data flow, navigate to the Integrate section, and click the New Data Flow button. Select the MailerLite connector tile, then select the credential that will be used to connect to the MailerLite account, and click Next; or, create a new MailerLite credential for use in this flow.

Endpoint templates

Nexla provides pre-built templates that can be used to rapidly configure data sources to ingest data from common MailerLite endpoints. Select the endpoint from which this source will fetch data from the Endpoint pulldown menu. Available endpoint templates are listed in the expandable boxes below.

[Rest API] List Subscribers

Returns a list of all subscribers in your MailerLite account.

This endpoint is paginated and returns subscriber records from the account. For details on response fields and pagination, see the MailerLite API Documentation.

[Rest API] List Segments

Returns a list of all segments in your MailerLite account.

This endpoint is paginated and returns segment records from the account. For details on response fields, see the MailerLite API Documentation.

[Rest API] List Automations

Returns a list of all automations in your MailerLite account.

This endpoint is paginated and returns automation records from the account. For details on response fields, see the MailerLite API Documentation.

[Rest API] List Campaigns

Returns a list of all campaigns in your MailerLite account.

This endpoint is paginated and returns campaign records from the account. For details on response fields, see the MailerLite API Documentation.

[Rest API] List Timezones

Returns a list of all available timezones supported by MailerLite.

This endpoint returns the full set of timezones in a single response and is not paginated. For details, see the MailerLite API Documentation.

[Rest API] List Popup Forms

Returns a list of all popup forms in your MailerLite account.

This endpoint is paginated and returns popup form records from the account. For details on response fields, see the MailerLite API Documentation.

[Rest API] List Embedded Forms

Returns a list of all embedded forms in your MailerLite account.

This endpoint is paginated and returns embedded form records from the account. For details on response fields, see the MailerLite API Documentation.

[Rest API] List Promotion Forms

Returns a list of all promotion forms in your MailerLite account.

This endpoint is paginated and returns promotion form records from the account. For details on response fields, see the MailerLite API Documentation.

[Rest API] List Webhooks

Returns a paginated list of all webhooks configured in the MailerLite account.

This endpoint is paginated and returns webhook records from the account. For details on response fields, see the MailerLite API Documentation.

[Rest API] Get Webhook

Retrieves detailed information about a specific webhook by its ID.

• Provide the webhook Id for the webhook you want to retrieve when configuring this endpoint.

For details on the returned webhook object, see the MailerLite API Documentation.

[Rest API] Get Webhook Count

Returns the total count of webhooks in the MailerLite account.

This endpoint returns a single count value and is not paginated. For details, see the MailerLite API Documentation.

Once the selected endpoint template has been configured, click the Test button to the right of the endpoint selection menu to retrieve a sample of the data that will be fetched. Sample data will be displayed in the Endpoint Test Result panel on the right, allowing you to verify that the source is configured correctly before saving.

Manual configuration

MailerLite data sources can also be manually configured to ingest data from any valid MailerLite API endpoint, including endpoints not covered by the pre-built templates, chained API calls, or custom request parameters. Select the Advanced tab at the top of the configuration screen, and follow the instructions in Connect to Any API to configure the API method, endpoint URL, date/time and lookup macros, path to data, metadata, and request headers.

Once all of the relevant settings have been configured, click the Create button in the upper right corner of the screen to save and create the new MailerLite data source. Nexla will now begin ingesting data from the configured endpoint and will organize any data that it finds into one or more Nexsets.

Use as a destination

Click the + icon on the Nexset that will be sent to the MailerLite destination, and select the Send to Destination option from the menu. Select the MailerLite connector from the list of available destination connectors, then select the credential that will be used to connect to the MailerLite account, and click Next; or, create a new MailerLite credential for use in this flow.

Endpoint templates

Nexla provides pre-built templates that can be used to rapidly configure destinations to send data to common MailerLite endpoints. Select the endpoint to which data will be sent from the Endpoint pulldown menu. Then, click on the template in the list below to expand it, and follow the instructions to configure additional endpoint settings.

[Rest API] Create or upsert a subscriber

Create or upsert a subscriber (core write operation for any email marketing integration).

Each record from your Nexset is sent as a JSON request body to create or update a subscriber. For the expected request format, see the MailerLite API Documentation.

[Rest API] Update an existing subscriber

Update an existing subscriber's fields, status, or group membership.

• Provide the Subscriber Id of the subscriber to update.

Each record is sent as a JSON request body to update the specified subscriber. For the expected request format, see the MailerLite API Documentation.

[Rest API] Delete a subscriber

Delete a subscriber (GDPR / opt-out compliance).

• Provide the Subscriber Id of the subscriber to delete.

This operation permanently removes the subscriber from your MailerLite account. For details, see the MailerLite API Documentation.

[Rest API] Bulk-import subscribers

Bulk-import subscribers (CSV or JSON array).

Records are sent as a JSON request body to import multiple subscribers into your account. For the expected request format, see the MailerLite API Documentation.

[Rest API] Bulk import subscribers into a group

Bulk import subscribers into a group.

• Provide the Group Id of the group to import subscribers into.

Records are sent as a JSON request body to import subscribers into the specified group. For the expected request format, see the MailerLite API Documentation.

[Rest API] Create a new subscriber group

Create a new subscriber group.

Each record is sent as a JSON request body to create a group. For the expected request format, see the MailerLite API Documentation.

[Rest API] Rename / update a subscriber group

Updates and renames an existing subscriber group in MailerLite.

• Provide the Id of the subscriber group to update.

Each record is sent as a JSON request body to update the specified group. For the expected request format, see the MailerLite API Documentation.

[Rest API] Delete a subscriber group

Delete a subscriber group by its unique ID.

• Provide the Id of the group to delete.

This operation removes the specified group from your account. For details, see the MailerLite API Documentation.

[Rest API] Create a custom subscriber field

Create a custom subscriber field.

Each record is sent as a JSON request body to create a custom field. For the expected request format, see the MailerLite API Documentation.

[Rest API] Update a custom subscriber field

Update a custom subscriber field label or type by providing the field ID and new field details.

• Provide the Id of the field to update.

Each record is sent as a JSON request body to update the specified field. For the expected request format, see the MailerLite API Documentation.

[Rest API] Delete a custom subscriber field

Delete a custom subscriber field by its unique identifier.

• Provide the Id of the field to delete.

This operation removes the specified custom field. For details, see the MailerLite API Documentation.

[Rest API] Create a new email campaign

Create a new email campaign.

Each record is sent as a JSON request body to create a campaign. For the expected request format, see the MailerLite API Documentation.

[Rest API] Update an existing campaign

Update an existing campaign's content or settings.

• Provide the campaign Id of the campaign to update.

Each record is sent as a JSON request body to update the specified campaign. For the expected request format, see the MailerLite API Documentation.

[Rest API] Schedule a campaign for delivery

Schedule a campaign for delivery.

• Provide the Campaign Id of the campaign to schedule.

Each record is sent as a JSON request body containing the delivery schedule. For the expected request format, see the MailerLite API Documentation.

[Rest API] Cancel a scheduled campaign

Cancel a scheduled campaign.

• Provide the campaign Id of the scheduled campaign to cancel.

For details, see the MailerLite API Documentation.

[Rest API] Delete a draft or cancelled campaign

Delete a draft or cancelled campaign.

• Provide the campaign Id of the campaign to delete.

This operation removes the specified draft or cancelled campaign. For details, see the MailerLite API Documentation.

[Rest API] Create Webhook

Creates a new webhook for the specified event with the provided callback URL.

Each record is sent as a JSON request body to create a webhook. For the expected request format, see the MailerLite API Documentation.

[Rest API] Update Webhook

Updates an existing webhook with new configuration settings.

• Provide the webhook Id of the webhook to update.

Each record is sent as a JSON request body to update the specified webhook. For the expected request format, see the MailerLite API Documentation.

[Rest API] Delete Webhook

Deletes a webhook, stopping it from receiving further event notifications.

• Provide the webhook Id of the webhook to delete.

This operation removes the specified webhook. For details, see the MailerLite API Documentation.

Manual configuration

MailerLite destinations can also be manually configured to send data to any valid MailerLite API endpoint. Select the Advanced tab at the top of the configuration screen, and follow the instructions in Connect to Any API to configure the API method, data format, endpoint URL, request headers, attribute exclusions, record batching, and response webhooks.

MailerLite APIs expect JSON format for write operations. For update, delete, and other operations that act on a specific object, include the object ID in the endpoint URL as required by the MailerLite API.

Save & activate

Once all endpoint settings have been configured, click the Done button in the upper right corner of the screen to save and create the destination. To send the data to the configured MailerLite endpoint, open the destination resource menu, and select Activate.

The Nexset data will not be sent to the MailerLite endpoint until the destination is activated. Destinations can be activated immediately or at a later time, providing full control over data movement.