> ## Documentation Index
> Fetch the complete documentation index at: https://developer.effilink.co/llms.txt
> Use this file to discover all available pages before exploring further.

# Send Marketing Campaign Emails with EffiLink

> Create and send bulk marketing emails to segmented contact lists using EffiLink's campaign API with scheduling and exclusion list support.

Marketing campaign emails are bulk messages sent to one or more contact lists — newsletters, product announcements, promotional offers, re-engagement sequences, and similar outbound communications. Unlike transactional email, campaign sends are audience-driven: you define *who* receives the message by targeting named contact lists in your EffiLink account.

The `/v5/campaign/mail/sends` endpoint lets you compose a campaign, target lists, apply exclusions, schedule delivery, and optionally save a draft without sending — all through a single API call.

***

## Workflow overview

Before sending a campaign, you need contacts organised into lists inside EffiLink. The typical workflow is:

```text theme={null}
Import contacts → Assign to contact lists → Send campaign targeting those lists
```

1. **Import contacts** — Upload or sync your contacts into EffiLink. See [Contacts](/docs/contacts) for how to create and manage contact lists.
2. **Target lists with `sendListNames`** — Specify one or more list names to receive the campaign.
3. **Compose and send** — Provide your email content (or a template), set a sender, and call the endpoint.

***

## Send a campaign

```json theme={null}
curl -X POST https://api.effilink.co/v5/campaign/mail/sends \
  -H "ApiKey: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "mailName": "June Newsletter",
    "senderMail": "hello@yourdomain.com",
    "senderName": "Your Brand",
    "subject": "What'\''s new in June",
    "content": "<h1>Hello!</h1><p>Here is what'\''s new this month...</p>",
    "sendListNames": ["newsletter-subscribers"],
    "trackOpen": 1,
    "trackClick": 1
  }'
```

A successful response returns:

```json theme={null}
{
  "code": 200,
  "message": "",
  "id": 1120,
  "guid": "915cb709ac96418495fcf4f666f15c0d"
}
```

### Required parameters

| Parameter       | Type   | Description                                                                  |
| --------------- | ------ | ---------------------------------------------------------------------------- |
| `mailName`      | string | Unique task name for this campaign send (max 200 bytes)                      |
| `senderMail`    | string | Verified sender email address                                                |
| `sendListNames` | array  | One or more target contact list names (required unless `onlySave` is `true`) |

### Optional parameters

| Parameter       | Type    | Description                                                                                   |
| --------------- | ------- | --------------------------------------------------------------------------------------------- |
| `senderName`    | string  | Sender display name                                                                           |
| `subject`       | string  | Email subject line                                                                            |
| `content`       | string  | HTML email body                                                                               |
| `replyTo`       | string  | Reply-to email address                                                                        |
| `attachment`    | object  | `{fileName, fileData}` — single base64-encoded file                                           |
| `languageCode`  | string  | Recipient language: `zh-cn`, `en`, `ja`, `ko`, `de`, `tt`, `es`, `zh-tw`, `ar`, `pt-br`, `id` |
| `marketName`    | string  | Associate this send with a marketing activity                                                 |
| `subscriptName` | string  | Associate with a subscription                                                                 |
| `projectCode`   | string  | Project code; auto-creates the project if it doesn't exist                                    |
| `editorType`    | string  | Editor type for UI: `CLASSIC` or `DRAG` (default: `DRAG`)                                     |
| `sandboxMode`   | boolean | `true` to validate without sending (see [Sandbox Mode](/docs/sandbox-mode))                   |

***

## Scheduling a campaign

Set `sendDate` to an ISO 8601 UTC timestamp to schedule the campaign for future delivery. Omit or leave empty to send immediately.

```json theme={null}
{
  "sendDate": "2024-07-01T08:00:00Z"
}
```

<Note>
  A/B test campaigns can be scheduled up to **30 days** in the future. Standard campaign sends should be scheduled as close to your intended delivery time as practical.
</Note>

***

## Saving a draft without sending

Pass `onlySave: true` to save the campaign configuration without dispatching any emails. This is useful for building drafts via the API for later review or launch via the EffiLink dashboard.

```json theme={null}
{
  "mailName": "July Sale Campaign",
  "senderMail": "promo@yourdomain.com",
  "subject": "Big July Sale — Up to 50% off",
  "content": "<p>Shop our biggest sale of the year.</p>",
  "onlySave": true
}
```

When `onlySave` is `true`, `sendListNames` is not required.

***

## Excluding contacts with `repelListNames`

Use `repelListNames` to specify one or more contact lists whose members should be **excluded** from receiving the campaign, even if they also appear in a targeted list. This is useful for suppressing recently-converted customers, unsubscribed users, or any segment you want to protect from a particular send.

```json theme={null}
{
  "sendListNames": ["all-subscribers"],
  "repelListNames": ["recent-purchasers", "unsubscribed"]
}
```

Exclusion is applied server-side before sending — contacts on a repel list will not receive the email regardless of overlap with `sendListNames`.

***

## A/B testing

EffiLink supports A/B testing for campaign emails, allowing you to compare subject lines, content variants, or sender names across a portion of your audience before sending the winning variant to the remainder.

A/B test parameters are configured at the campaign level. For the full schema — including split percentages, winning criteria, and wait periods — refer to the [Campaign Sends API reference](/api/campaign-sends).

***

## Attaching a file

Attach a single file to your campaign email using the `attachment` object. File content must be **base64-encoded**.

```json theme={null}
{
  "attachment": {
    "fileName": "june-catalog.pdf",
    "fileData": "JVBERi0xLjQKJ..."
  }
}
```

***

## Next steps

* [Manage contact lists](/docs/contacts) — Import and segment your audience
* [Campaign Sends API reference](/api/campaign-sends) — Full parameter schema, A/B test options, and response details
* [Sandbox Mode](/docs/sandbox-mode) — Validate your campaign request without sending
* [Email Tracking](/docs/email-tracking) — Track opens and clicks for your campaign