Lists & Tags

A list is a named, static group of contacts. When you add a contact to a list, they stay in that list until explicitly removed — membership doesn't change based on contact properties (that's what Segments are for).

Common ways to use lists:

• Newsletter subscribers — everyone who signed up for your weekly newsletter via a signup form.
• Trial users — contacts synced from your app when they start a trial.
• Customers — contacts who have made a purchase.
• Event attendees — contacts registered for a specific webinar or event.
• Cold prospects — imported contacts from a sales campaign (to be excluded from newsletter sends).

A single contact can belong to multiple lists simultaneously. They receive a campaign once even if they're on multiple targeted lists.

Go to Contacts → Lists → New List.

• Name: required. Visible in the dashboard and used when selecting campaign audiences. Choose a clear, descriptive name like "Newsletter Subscribers" or "Paying Customers Q1 2026".
• Description: optional. Helps team members understand the list's purpose. Not visible to contacts.

You can also create a list via the API:

curl -X POST https://emailsendx.com/api/v1/lists \
  -H "Authorization: Bearer esx_live_your_api_key" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Newsletter Subscribers",
    "description": "Weekly product newsletter opt-ins from the website"
  }'

# Response:
{
  "id": "lst_02jy5lqrs0waf9x4u6o3n8c7g",
  "name": "Newsletter Subscribers",
  "description": "Weekly product newsletter opt-ins from the website",
  "contact_count": 0,
  "created_at": "2026-04-22T10:00:00Z"
}

There are several ways to add and remove contacts from a list:

From a contact profile

Open any contact profile. In the Lists section on the right sidebar, click Add to List and search for or select a list. To remove, click the X next to any list name.

During CSV import

When importing contacts, select a list on the import configuration screen. All successfully imported contacts will be added to that list. This is the fastest way to populate a new list.

Via API

Set list membership at contact creation time by passing list_ids in the request body:

# Add a new contact directly to one or more lists
POST https://emailsendx.com/api/v1/contacts
{
  "email": "new@example.com",
  "first_name": "Alex",
  "list_ids": ["lst_02jy5lqrs0waf9x4u6o3n8c7g"]
}

For ongoing list membership changes (adding/removing existing contacts, listing members), use the dashboard or an automation with the Move to List action — direct member-management endpoints are not currently exposed via the public API.

Via automation

Use the Move to List action in an automation to add or remove contacts from lists based on triggers and conditions. For example, move a contact from a "Trial Users" list to a "Customers" list when they complete a purchase event. See Automations for details.

Tags are simple string labels applied to individual contacts. Unlike list membership, tags are stored directly on the contact record and are ideal for lightweight, flexible categorization.

When to use tags vs lists:

Adding and removing tags

Tags can be managed from the contact profile, during CSV import (apply tags to all imported contacts), or via automation actions (the Tag Applied trigger and the Add/Remove Tag action).

To filter contacts by tag for export or reporting, use the contacts list query:

# Filter contacts by tag
GET https://emailsendx.com/api/v1/contacts?tag=vip

The lists API lets you list and create lists programmatically. All endpoints require a valid Bearer token.

# List all lists in the workspace
GET https://emailsendx.com/api/v1/lists
# Query params: page, limit (default 20, max 100)

# Create a new list
POST https://emailsendx.com/api/v1/lists
{
  "name": "Product Updates Subscribers",
  "description": "Contacts who opted in to product announcements"
}

List rename, delete, and member-level operations (add/remove/list members) are managed from the dashboard. Direct CRUD endpoints for individual lists are not currently exposed via the public API.