Transactional Email

Transactional emails often contain highly sensitive personal data: password reset links, two-factor authentication codes, order confirmations with addresses, medical appointment details, and financial statements. Unlike marketing emails, users cannot opt out of receiving them since they are essential for service functionality. This means your transactional email provider processes sensitive data for every active user, not just subscribers who opted in. A breach or unauthorized access at your email provider's infrastructure could expose your entire user base.

Most transactional email providers use similar REST API and SMTP patterns, so switching is straightforward. You typically change API endpoints, authentication keys, and adjust your template syntax. European providers like Mailjet, Brevo (Sendinblue), and Mailtrap offer client libraries for popular programming languages. A migration can often be completed in a day for simple setups. The biggest effort is usually re-creating email templates and verifying deliverability for your sending domains.

Under GDPR, email delivery logs containing recipient addresses, timestamps, and content metadata are personal data. European transactional email providers typically offer configurable log retention periods, allowing you to set automatic deletion after 7, 30, or 90 days. Some providers let you disable content logging entirely while keeping delivery status only. This is important for minimizing the personal data you retain, a core GDPR principle. US providers often retain logs indefinitely by default.