
Retarus Transactional Email
Retarus Transactional Email sends high volumes of transactional emails from business applications through Retarus Enterprise Cloud.
What Retarus Transactional Email is
Retarus Transactional Email sends high volumes of transactional emails from business applications through Retarus Enterprise Cloud. Businesses can connect through REST API or SMTP interfaces, using JSON or SMTP/MIME data formats, and Retarus says it integrates directly with SAP, Microsoft, Salesforce and ServiceNow applications. The service offers SMTP basic authentication, SMTP source-IP authentication and REST basic authentication. Retarus states a delivery rate of 98% or higher and guaranteed processing capacity of 100,000 emails per hour; its Email API page states capacity of up to 10 million per hour. Administrators can use the myEAS web portal for dashboards, real-time monitoring, reports and self-service configuration. Security features include SPF, DKIM, DMARC, enforced TLS, antivirus multiscan, encrypted attachments and message signing. Retarus processes data in its own data centers in Germany, Switzerland, the United States and Asia. Pricing is available on request. The free trial lasts 30 days, allows up to 5,000 emails and limits processing to 200 emails per hour; it does not allow load testing.
Good
- Provides REST API and SMTP interfaces.
- Integrates with SAP, Microsoft, Salesforce and ServiceNow.
- Includes real-time monitoring and reporting through myEAS.
- Offers a 30-day free trial.
- Supports email search with status information for the past 45 days.
Watch out
- Trial is limited to 5,000 emails.
- Trial processing is capped at 200 emails per hour.
- Trial does not allow load testing.
- Commercial pricing is available on request.
Who it suits
The service is aimed at software vendors, platform businesses, large enterprises and highly regulated industries that send transactional email from business applications. It may suit teams that need REST or SMTP integration and administrative monitoring.
Verdict
Retarus Transactional Email offers API and SMTP delivery with administrative monitoring and multiple email security measures. The trial has volume and processing limits, while commercial pricing requires a request.
Plans and prices
From Retarus Transactional Email's own pricing page, checked 1 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Free trial | Free | 30 days · maximum 5,000 emails · maximum 200 emails/hour · no load testing |
| Transactional Email | Priced on request | REST and SMTP APIs · contractually guaranteed throughput · schedule a demo |
The facts
Each one read from Retarus Transactional Email's own pages, with the date it was checked.
What it does
- Authentication
- Available authentication methods include SMTP basic authentication, SMTP source-IP authentication, and REST basic authentication.checked 1 Oct 2026
- Compliance
- Retarus states that its data centers fulfill requirements including EU GDPR, HIPAA, Sarbanes-Oxley, PCI DSS, CAN-SPAM, and TISAX.checked 1 Oct 2026
- Data centers
- Retarus processes data in self-operated data centers in Germany, Switzerland, the United States, and Asia, without hyperscalers.checked 1 Oct 2026
- Dedicated IP option
- Yeschecked 20 Sep 2026
- Delivery methods
- bothchecked 20 Sep 2026
- Delivery rate
- Retarus states a delivery rate of 98% or higher.checked 1 Oct 2026
- Email search
- The Email API supports searching outbound emails by time period, message ID, sender, and recipient, with status information for the past 45 days.checked 1 Oct 2026
- Email security
- Features include SPF, DKIM, DMARC, enforced TLS, antivirus multiscan, encrypted attachments, and message signing.checked 1 Oct 2026
- Event webhooks
- Yeschecked 20 Sep 2026
- Integrations
- Retarus says Transactional Email integrates directly with SAP, Microsoft, Salesforce, and ServiceNow business applications.checked 1 Oct 2026
- Interfaces
- Transactional Email provides REST API and SMTP interfaces, with JSON and SMTP/MIME data-format support.checked 1 Oct 2026
- Monitoring
- The myEAS web portal provides dashboards, real-time monitoring, reporting, and self-service configuration for administrators.checked 1 Oct 2026
- Purpose
- Sends large volumes of transactional emails directly from business applications through Retarus Enterprise Cloud.checked 1 Oct 2026
- Support
- Retarus describes support from expert staff with no call center or chatbots, covering scope, migration, production, and go-live.checked 1 Oct 2026
- Target customers
- Retarus identifies software vendors, platform businesses, large enterprises, and highly regulated industries as target users.checked 1 Oct 2026
- Throughput
- The service states guaranteed processing capacity of 100,000 emails per hour, while its Email API page states capacity of up to 10 million emails per hour.checked 1 Oct 2026
The company
- Founded
- 1992checked 28 Sep 2026
- Headquarters
- Munich, Germanychecked 28 Sep 2026
Money
- Trial restrictions
- The documented free trial is limited to 30 days and 5,000 emails, with no more than 200 emails processed per hour.checked 1 Oct 2026
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