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Alex Nowak
Written by Alex Nowak

How to send emails with custom SMTP settings

Enhance email customization with your own SMTP settings

Why is it worth connecting your SMTP? SMTP service offers you a high deliverability and reliability rate.

Alternatively, if you have your own provider for email delivery, you may choose to use that instead. This option allows you to fully customize your SMTP server settings to meet your individual needs. The best thing is that you will keep using exactly like before. The primary difference lies in the distinct server used to send your email messages.

However, please note that when using your own SMTP, the range of statuses in email campaign reports will be reduced - the NDR (non-delivery, i.e. softbounce, hardbounce) metrics won’t be included. These will be reported directly to your server instead.

How to connect your custom SMTP?

  1. Make sure that in your email settings, you have enabled connection to third-party services. If you are using Gmail, you may have to change the security settings to allow the connection. If Google apps are being used, the administrator is the only person authorised to change those settings. Here is a full article on that.

  2. Go to "Settings" -> "SMTP settings"

  3. Click the button, "Create SMTP", and start filling out the form.

Here are all the fields:

  • SMTP server:You need to find your mailing service provider host address. For Gmail, use

  • User: In most cases, this is simply the email address of the account you want to use.

  • Password: The password to your mailing account or a unique password if you have 2-step verification on your email account (instruction here).

  • Email address: Email address you are planning to use to send emails from.

  • Reply to address:The email address to which responses to emails are redirected to; (You can use your application email address in order to get replies right on chat).

  • Sender Name: Allows you to personalize the message.

  • SSL: A security certificate; we strongly recommend using it if your provider allows one. (Please remember to turn it off for Gmail).

  • TLS: Security protocol, whether you can use it or not depends on the provider as well. For Gmail, please turn it on.

  • Port Number: Depends on the provider (for Gmail, use 587).

  • Set as default for: You can specify for which agents this SMTP will be the default setting.

  • Description: For better organization, you can add a description of this SMTP.

After you finished configuring your custom SMTP settings, it will appear as a new sender option. You can use it while creating an email campaign or in other places in the app where you can send messages to a specific user.

Example from campaign's creator view:

How to adjust message throttling? will send emails as quickly as possible, even up to several hundred emails per second. Make sure that your SMTP server has appropriate "throttle rate" limits to avoid delivery failures.

If you notice failures in the 'Delivery log' tab of your campaign report, and the error message reads something like:

"SMTP Error 454 b'Throttling failure: Maximum sending rate exceeded'"

it indicates that the server is sending out emails faster than your SMTP server can handle.

There are two solutions:

  • ask your SMTP administrator to increase the limit

  • send automated campaign, using the Randomize option in "Delay" module. Learn more here.

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