What is SMTP and how can I use it ?

SMTP stands for Simple Mail Transfer Protocol - it is an internet standard for email transmission.

Moosend offers a direct SMTP service which you can integrate with your existing applications, or utilize to send transactional emails directly using your favourite SMTP client. Keep in mind that the SMTP service is not available on the free Moosend accounts. 

To take advantage of our SMTP service and send transactional emails, you first need to connect your Moosend account to your application or SMTP client. All you need to do is grab a couple of configuration lines from our platform and add them to the application of your preference. No experienced technical team is needed and the service is already there for you to use, so let's see how it's done: 

A. Finding the configuration information

1. Click on the Mailing lists button located on the left side menu.step1.png

2. Click on the name of a mailing list.

3. Click on the Direct SMTP button on the vertical bar that appears.

4. You can find all the details you need to connect to our SMTP service, here. 

The details you can see here, are: 

  • SMTP Hostname 
    This is the Hostname that you will use to connect to our standard SMTP service.

  • SMTP Port
    This is the SMTP port that will use to connect to our standard SMTP service. You can use the ports 25, 587, 25000 or 465. Note that the ports 465 and 587 support TLS encryption. We suggest to use port 25 or 587 which are the standard SMTP ports but if you prefer to use any of other ports mentioned, feel free to use them!

  • SMTP Username
    This is your account's username - yes, this is the one you use to login into your Moosend account! Note that if you are using a sub-account, you must provide your Moosend domain in the username as well. So if for example your moosend domain name is, your SMTP username should be myaccount\username 

  • SMTP Password
    This is your account's password - yes, this is the one you use to login into your Moosend account! Note that if you are using a sub-account, you first need to create a password for your sub-account. 

B. Selecting the recipients of your SMTP campaign  

You can use our standard SMTP to send your campaigns to a single email address or to a Moosend mailing list.

  • To send your SMTP campaign to a single email address, simply decide the content of your SMTP campaign and sent it to this person by including his email address.

    Once your SMTP campaign is sent, a new mailing list will be created with name "Transactional Campaign Recipients" on your Moosend account and every time you send a campaign to a single email address, the recipients will be added to this "Transactional Campaign Recipients" mailing list. If you prefer your subscribers to be added to a specific Moosend mailing list, just ensure that you added the appropriate GUID on the headers of the email. 

    What you are looking for, is the following GUID:

    • mailing_list_id: your-mailing-list-id-here
      This allows all the recipients to be added using the same mailing list ID.

  • To send your SMTP campaign to a Moosend mailing list, fist of all you need to make sure that you have already imported the members to your mailing list. Then you can send your SMTP campaign to On this email address, you will need to replace the mailing_list_id with your own mailing list id.

    If for example the mailing list id of your list is 6d2849086-f535-48aa-bf77-542b0d8da338, the email address you should send it is 

    You can also find this information in the Direct settings of your mailing list.


C. Reporting of your SMTP campaign 

You can connect to our standard SMTP service to send your campaign and simply track its statistics on your Moosend account!

Emails sent from SMTP will be treated like they belong to a campaign. The system creates a campaign named "Transactional Campaign" for each user where all opens and clicks are registered. It also creates a mailing list named "Transactional Campaign Recipients" where all recipients from transactional emails are stored.

If you want to track statistics with a different campaign you can create a campaign on the platform with subject equal to the subject of your transactional email. When a campaign subject matches the subject of the transactional email, all opens and clicks are registered to this campaign. This also means that any new members will be added to the mailing list that is connected with the campaign that has the same subject on your Moosend account. 

Alternatively, you can specify which campaign tracks your transactional emails using email headers. Email headers are extra information passed to the email message and can usually be added only by code. Adding the appropriate GUID on the headers of the email will send all statistics to that campaign. Check the documentation of the programming language you use on how to send emails with custom headers.

What you are looking for, is the following GUID:

  • campaign_guid: your-campaign-id-here
    This is the ID of your campaign, whose statistics will be recorded for every transactional email sent through our SMTP service.

Don't forget that you can also specify a mailing list to store the recipients of transactional emails. Adding the appropriate GUID on the headers will send all new recipients to that mailing list.

What you are looking for, is the following GUID:

  • mailing_list_id: your-mailing-list-id-here
    This allows all the recipients to be added using the same mailing list ID.