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title: Subject Authentication 
description: SMS Global Knowledgebase
---

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# Subject Authentication 

## Details on the subject authentication method for Email to SMS (alternative to whitelisted allowed sender email)

To send an Email to SMS using subject authentication instead of allowed senders, send an email with the subject line containing the following format:

 

```
auth~{HTTP_API_USERNAME}:{HTTP_API_PASSWORD}~Email Subject
```

 

Insert your SMS content into the body of the email.

 

The HTTP API username and HTTP API password can be found in the ***API Integrations*** page located [here](https://mxt.smsglobal.com/integrations) under ***'Master API Keys'***.

 

Any replies to Email to SMS sent via this method will behave the same way as using allowed senders, which can be seen [here](https://mxt.smsglobal.com/integrations/email-to-sms).

 

***Note:* ~Email Subject** portion is optional and does not need to be included.

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