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Configure Postmark in FluentSMTP ​

With FluentSMTP, you can integrate Postmark into WordPress to improve email deliverability and authenticity. Postmark is one of the leading mailer options for WordPress, that is reliable and easy to set up.

This article will guide you through integrating Postmark into WordPress using the FluentSMTP plugin to send emails via SMTP.

Prerequisites ​

Configuring Postmark ​

Go to Settings in the FluentSMTP top bar. If you haven't set up any connection yet, the setup wizard opens automatically. Otherwise, click the + Add Connection button.

Then select the Postmark icon from the provider grid.

NOTE

If you want to change the connection provider, click the change button next to the provider logo at the top of the page.

This opens the connection form, where you provide:

  • From Email and From Name
  • Force Sender Name: Uses this connection's From Name, whatever name the sending plugin set.
  • API Key: Obtained from your Postmark account via the Postmark Server link, described in the next section.
  • Track Opens: Adds an open-tracking header to emails sent through Postmark (HTML emails only).
  • Track Links: Adds a link-tracking header to emails sent through Postmark (HTML emails only).
  • Message Stream: Postmark separates email into Transactional Stream for individual messages like password resets and order confirmations, and Broadcast Stream for bulk emails like newsletters and marketing campaigns. Enter the Message Stream ID that matches the type of email you plan to send. This defaults to outbound.

The rest of this guide walks through getting the API Key from Postmark, then pasting it into this form.

Get Postmark API Key ​

First, log into your Postmark Account, and select your Server (e.g., My First Server). If you want to create a new server, click the Create Server button.

Name your server, pick a color label, and choose a Server Type: Live to deliver messages to recipients, or Sandbox to send messages to a test inbox. This choice is permanent, so pick the one that matches how you plan to use this server. Then click the Create Server button.

Now, open the API Tokens tab. You will find your key under Server API tokens, next to copy it. If you want to generate a new key, click the Generate another token button.

Then, go back to the Add Connection page under Settings in the FluentSMTP top bar, and paste the API Key you copied from Postmark inside the API Key box.

Once you input all the necessary information, click the Save Connection Settings button. Your Postmark server will be connected to your FluentSMTP.

Details of Postmark API Settings ​

  • Store in Database: By default, this is enabled and strongly recommended. This will keep the information in the database in encrypted format. Tick Disable Encryption for API Key (Not Recommended) only if a security plugin rotates your SALT keys and the encrypted value keeps breaking.
  • Store in wp-config.php: This allows you to store the access key inside the wp-config.php file by the following directive.

Copy the snippet below, replace the stars with your own credential, and paste it into your site's wp-config.php file.

define( 'FLUENTMAIL_POSTMARK_API_KEY', '********************' );

Configured Postmark ​

Here, you can see that your Postmark connection is listed under Active Email Connections. Click the … menu next to it to Set as Default, Set as Fallback, View, or Delete the connection.

To learn the details about General Settings, read this documentation. Additionally, it is recommended to send a test email to check whether the configuration is successful, to learn how to send a test email in detail, read this documentation.

That's all about configuring FluentSMTP with Postmark to send emails from the WordPress website.

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