The overwhelming consensus is that Klaviyo does not support integrating an external SMTP server. Experts, email marketers, and Klaviyo's own documentation confirm this. The primary recommendations are to either use alternative SMTP services like Mailgun, Sendgrid, or Mandrill *with* Klaviyo (although it's understood this doesn't *integrate* the SMTP, but uses it in another context), or to migrate to a different email marketing platform that offers SMTP integration, such as ActiveCampaign, Mailjet, Amazon SES or Sendinblue. Technical insights into SMTP setup and relay are useful if considering a platform migration.
10 marketer opinions
The overwhelming consensus is that Klaviyo does not natively support integration with external SMTP servers. Users seeking this functionality are advised to consider migrating to alternative email marketing platforms like ActiveCampaign, Mailjet, Amazon SES, or Sendinblue, or to use services like Mailgun, Sendgrid, or Mandrill.
Marketer view
Email marketer from Reddit mentions that Klaviyo is a closed system and it’s not possible to use your own SMTP server. They recommend looking into platforms like ActiveCampaign if you need that level of control.
10 Oct 2023 - Reddit
Marketer view
Email Marketer from LitExtension shares that if you're not happy with Klaviyo's native SMTP, your best option is to migrate your email marketing to a platform that allows external SMTP integration. They provide a guide for migrating from Klaviyo.
22 Jan 2024 - LitExtension Blog
3 expert opinions
Experts generally agree that integrating an external SMTP with Klaviyo is not directly possible. The recommendations lean towards using alternative services like Mailgun, Sendgrid, or Mandrill. Furthermore, maintaining a properly configured SMTP server is crucial for deliverability, suggesting that if such control is necessary, switching platforms away from Klaviyo should be considered. Insights into SMTP relay setup are helpful for those considering switching to another platform.
Expert view
Expert from Email Geeks suggests not integrating an external SMTP to Klaviyo and using Mailgun, Sendgrid, or Mandrill instead.
23 Feb 2022 - Email Geeks
Expert view
Expert from Spamresource details about SMTP relay setup, it highlights technical aspects of SMTP servers. Though it doesn't directly address Klaviyo, it provides valuable insight for setting up your own SMTP server if you were to switch away from Klaviyo for this functionality. This is on a page discussing port 25 issues.
19 Nov 2021 - Spamresource
5 technical articles
Official documentation confirms that Klaviyo does not support integration with external SMTP providers. While Klaviyo utilizes its own infrastructure, documentation from SendGrid, Mailgun, Amazon SES, and ActiveCampaign offer insight into SMTP integration practices, beneficial for users considering migration from Klaviyo to platforms that do support external SMTP.
Technical article
Documentation from Mailgun details how to set up SMTP relay. Useful for users considering switching from Klaviyo to Mailgun to achieve SMTP integration.
4 Oct 2021 - Mailgun
Technical article
Documentation from ActiveCampaign explains how to integrate external SMTP providers with ActiveCampaign. This provides context on SMTP integrations generally, which can be useful if migrating from Klaviyo.
12 Sep 2022 - ActiveCampaign
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