Mailofly
Mission-Critical Transactional Email Infrastructure

Reliable Transactional Email Delivery for Modern Apps

Deliver OTPs, receipts, and user notifications in under 2 seconds. Engineered with dedicated transactional routing, sub-100ms API latency, and 99.99% uptime SLA.

Start Sending Transactional EmailsExplore Email API
<2.0s
Inbox Arrival Time
99.99%
Uptime SLA
3,000
Free Emails / Month
100%
Isolated IP Routing
Core Workloads

Built for Every Transactional Need

Sub-2s Delivery

Authentication & 2FA Codes

Deliver OTPs, magic links, and password resets in under 2 seconds. Direct MX routing ensures zero login friction.

Financial Reliability

Order Receipts & Invoices

Send Stripe and LemonSqueezy payment confirmations, billing receipts, and subscription renewal notices.

High Priority

Real-Time System Alerts

Notify engineers and workspace members about security anomalies, background jobs, and team invitations.

Architecture

Zero Outage Transactional Infrastructure

Your transactional emails carry essential business value. We ensure they land in the inbox without delay.

Dedicated High-Priority Ingest

Transactional messages bypass bulk marketing queues entirely. Critical auth tokens and receipts are dispatched instantly without waiting in line.

Multi-Provider Failover

If a major cloud provider experiences an outage, Mailofly automatically redirects your transactional traffic across redundant backbones with zero downtime.

Strict SPF, DKIM & DMARC Enforcement

Avoid the dreaded spam folder. Automated DNS alignment guarantees that Gmail and Yahoo recognize your emails as trusted authentication notices.

30-Day Searchable Event Logs

Search by recipient email or message ID to verify delivery times, opened states, bounce errors, and complete SMTP conversation transcripts.

Best Practices

Transactional vs. Marketing Email

Understand why keeping transactional traffic separate from marketing campaigns protects your inbox deliverability.

AspectTransactional EmailMarketing Email
TriggerAutomated user action (login, order, reset)Scheduled broadcast / campaign send
Delivery Speed Target< 2 secondsMinutes to hours
Unsubscribe LinkNot required by CAN-SPAM / GDPRMandatory 1-click unsubscribe
IP IsolationDedicated high-reputation IP poolStandard campaign pool
Common Questions

Frequently Asked Questions about Transactional Emails

A transactional email is a one-to-one, automated email triggered by a user action or system event—such as a password reset request, two-factor authentication (2FA) code, order receipt, or security alert. Unlike marketing newsletters, transactional emails contain critical, non-promotional information that users expect to receive immediately.

Send Your First Transactional Email in 5 Minutes

3,000 free emails each month. No credit card required. Instant API key provisioning.

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