This week Mandrill announced that it will be discontinuing its free tier for transactional emails. As of March 16th, new Mandrill users will create their accounts through MailChimp and existing users will be required to merge their accounts with a MailChimp account where they will be charged $20+/mo for transactional emails. The deadline for merging accounts is April 27th.
MailChimp is choosing to focus on delivering “personalized transactional” emails that require more design. For those who want to continue delivering utility type emails, the company recommends Amazon SES:
Transactional emails, like password reminders and the myriad email notifications you get after making changes to online accounts, are dead simple. Utilitarian providers like Amazon SES excel at this. Their innovation is mostly focused on increasing efficiency and reducing costs.
Many WordPress developers depend on Mandrill for sending wp_mail() emails in order to ensure delivery and take this load off the server. After MailChimp’s announcement, many are scrambling to find an alternative.
Amazon SES allows users to send 62,000 messages per month to any recipient, as long as you call it from an Amazon EC2 instance. If you already have one set up, this is one of the best options.
Human Made created an open source plugin that makes it easy to change to Amazon SES. Setting it up is as simple as adding a few constants to your wp-config.php file and then verifying your sending domain for SES.
Of course, Amazon SES isn’t the only option. Remkus de Vries wrote a post on transactional email alternatives to Mandrill, which includes MailGun (10,000 emails free every month), SendGrid (up to 12,000 emails free per month), SendIn Blue (up to 9,000 emails/month, 300 emails/day free), and several others. Many of these email services also have corresponding plugins available in the WordPress Plugin Directory.
Source: WP Tavern