Flexible integration
Choose a REST-based Email API or standard SMTP relay to fit modern applications and existing systems.
Transactional Email Service
Reliable Transactional Email Service for Critical Messages
Deliver the emails your customers expect—OTPs, receipts, security alerts, and account updates—with scalable infrastructure, delivery visibility, and flexible Email API or SMTP relay integration.
Core capabilities
- Email API and SMTP relay
- Delivery and bounce visibility
- Built for automated sending
Connect existing systems and manage email delivery performance from one platform.
Make every business-critical email count
Transactional email is triggered by a customer action or a business event. Unlike promotional campaigns, these messages carry information a recipient is actively waiting for, so speed, reliability, and clear delivery feedback matter.
uSpeedo helps product and operations teams send transactional emails from existing applications and workflows. Use programmable APIs for direct product integration or SMTP relay when your system already supports standard SMTP.
Built for dependable delivery
Transactional email capabilities for every stage of growth
Connect your product, automate event-driven messages, and monitor delivery performance from one email sending service.
Delivery diagnostics
Track delivery, bounce, and engagement events so teams can identify issues and respond quickly.
Sender reputation safeguards
Use domain authentication support, monitoring, and responsible sending controls to protect long-term performance.
Scalable automation
Support growing event-driven volumes without rebuilding the email layer as your product expands.
Reusable templates
Keep receipts, alerts, and lifecycle messages consistent with reusable, branded email templates.
Global customer communication
Operate transactional email programs for customers across markets from a unified sending platform.
Transactional emails for important customer moments
Send timely, expected messages across the customer lifecycle.
Verification and security
Send email OTPs, sign-in alerts, password resets, and account verification messages.
Orders and payments
Deliver order confirmations, receipts, invoices, payment updates, and refund notifications.
Product notifications
Keep users informed about account activity, service changes, usage alerts, and workflow updates.
Lifecycle communication
Trigger welcome emails, onboarding steps, renewal reminders, and subscription confirmations.
Start sending transactional email in four steps
Choose the integration path that matches your application and current infrastructure.
- 01
Verify your sender
Set up the sending identity and authentication records used by your business.
- 02
Choose API or SMTP
Use the Email API for direct integration or SMTP relay for systems that already speak SMTP.
- 03
Connect events and templates
Map product events to the right transactional template and recipient data.
- 04
Monitor delivery
Review delivery status, bounces, and engagement signals as sending volume grows.
FAQ
Frequently asked questions
What is a transactional email service?+
A transactional email service sends automated, one-to-one messages triggered by a user action or business event, such as an OTP, receipt, password reset, or account alert.
Can I send transactional email through SMTP?+
Yes. uSpeedo supports standard SMTP relay for existing applications and email systems, as well as a programmable Email API for direct product integration.
How is transactional email different from marketing email?+
Transactional email delivers expected information related to an action or account. Marketing email is promotional and is generally sent to opted-in audiences as part of a campaign.
Can I track failed or bounced transactional emails?+
uSpeedo provides delivery, bounce, and engagement event visibility so teams can monitor performance and investigate sending issues.
Email API & SMTP Relay
Get startedBuild reliable transactional email into your product
Start with Email API or SMTP relay and scale your automated customer communication with uSpeedo.
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