# Booster for e-mail campaigns

## Intro 

Booster is a tool that enables automatic follow-up messaging within a campaign. Available in the MessageFlow panel, it lets you schedule automated messages to be sent within a specific timeframe (from 2 hours up to 7 days) to recipients who didn’t open the original message. Booster can be used with Email, SMS, and PUSH campaigns.

{% hint style="warning" %}
For Email campaigns, Booster allows you to send an additional SMS or Email. Please note: the Booster feature is not available for A/B test campaigns.
{% endhint %}

## **Example use case**

You’re launching an Email campaign promoting products with a discount that ends in 7 days. After the initial send, you receive a performance report. Three days before the promotion ends, an automatically scheduled follow-up SMS or Email is sent to those who didn’t open the first message.

## Billing

Messages sent as part of a campaign with Booster enabled are billed according to your account settings and existing contract. All Booster-sent SMS and Emails appear under the Campaign tab with the name “Booster for....”.

## Where to find Booster in email campaigns

You can enable Booster during the final step of setting up your Email campaign — the summary stage. The Booster function is turned off by default and must be activated manually.

<figure><img src="https://lh7-qw.googleusercontent.com/docsz/AD_4nXdFMzbVG6uGtY1OaGzke6F-7zsvgcmMiMSISCfROCAkjGpbkifQWFr5fOEsLwWDly-90t4u1LJRxtnocR62io0n7DFB-Zrpz6UK1THCykEYdyUU5R9P_6ZGTSfT5OpJIWH_LAwy?key=RDfWvzg2eAMZ0zhsBO2XbA" alt=""><figcaption></figcaption></figure>

## Access and permissions

If your account does not include SMS capabilities, the Booster option will be greyed out. A message will prompt you to contact our sales team to unlock the feature.

<figure><img src="https://lh7-qw.googleusercontent.com/docsz/AD_4nXeOeoeZcYUmeJtIIogRHkQOLqBS48qoZJE57ZamGwaVApWJR7V4g2Xx1O-U6eWXlxyn5uBMYYlskqw5fSJmKpqP6eC63fyI-GcFv6XTFUQHacuhchZr-PGxtTNJvEuvdVRu-QQWGg?key=RDfWvzg2eAMZ0zhsBO2XbA" alt=""><figcaption></figcaption></figure>

## Audience selection

Booster messages are targeted at users from the original campaign audience who, within a defined window (2 hours to 7 days), did not open or click the original message.

Importantly, contacts are selected just before the Booster send. If a recipient opens the original message shortly before the Booster is scheduled, gets deleted, or is blocked — they will be excluded.

The list of contacts who received the Booster is not visible in the Groups section. You can find this data in the [campaign report](https://docs.messageflow.com/email/e-mail-campaigns/campaigns/campaign-list).

## Booster eligibility based on main campaign status

| **Main channel** | **Status** | **Booster channel** | **Booster delivery**                                  |
| ---------------- | ---------- | ------------------- | ----------------------------------------------------- |
| email            | HARDBOUNCE | email               | <mark style="background-color:red;">Not sent</mark>   |
| email            | HARDBOUNCE | SMS                 | <mark style="background-color:green;">Possible</mark> |
| email            | SOFTBOUNCE | email               | <mark style="background-color:green;">Possible</mark> |
| email            | SOFTBOUNCE | SMS                 | <mark style="background-color:green;">Possible</mark> |
| email            | SPAMBOUNCE | email               | <mark style="background-color:red;">Not sent</mark>   |
| email            | SPAMBOUNCE | SMS                 | <mark style="background-color:green;">Possible</mark> |

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**Booster messages will not be sent to:**

* Recipients who opened or clicked the main campaign message
* Deleted contacts
* Blocked contacts
* Contacts without a phone number
* Groups with 0 contacts
* Groups with 100% open rate for the main campaign (you’ll be notified if Booster gets cancelled for this reason)
* Contacts marked as "Spambounce" after the main Email campaign (applies to Email→ Email follow-ups)

## Unsubscribe link

Unsubscribing from a Booster campaign works the same way as with [other campaign types](https://docs.messageflow.com/email/e-mail-campaigns/settings/adding-a-sign-out-page).

{% hint style="success" %}
**Want to learn more about the capabilities of Message Booster?**

See how it works, explore its benefits, and discover how it can boost your campaign performance on the product page: [**Message Booster**](https://messageflow.com/message-booster/)
{% endhint %}