Overview
Founded in 2019 and headquartered in London, United Kingdom, MailerSend is a developer-focused email sending API platform. It offers 12,000 free emails per month and supports both SMTP and RESTful API for transactional email, notification, and marketing email use cases.
MailerSend prioritizes developer experience with multi-language SDKs and well-documented APIs, enabling teams to integrate email sending within minutes. Its built-in responsive email template editor, real-time sending logs, and delivery analytics dashboard make it an ideal choice for small to medium development teams seeking rapid integration and transparent operations.
Key Strengths
- Generous Free Tier: 12,000 free emails per month with no credit card required, significantly lowering the barrier for startups and developers to get started.
- Developer-Friendly API: Multi-language SDK support (Python, PHP, Node.js, Ruby, Go, Java) with comprehensive API documentation and Postman collections — first email sent in under 15 minutes.
- Responsive Email Templates: Drag-and-drop template editor with variable insertion and conditional logic, enabling cross-client compatible email creation without frontend expertise.
- Real-Time Sending Insights: 72-hour data retention on sending logs with filtering by domain, type, and status, helping quickly identify bounces and delivery delays.
Product Ecosystem
- Transactional Email API: Dedicated high-reliability channel for verification emails, password resets, and order notifications, ensuring critical messages are prioritized.
- SMTP Relay: Standard SMTP interface compatible with WordPress, Postfix, and other SMTP clients — integrate without modifying existing systems.
- Email Template Management: HTML-based responsive template engine with dynamic variables (
{{name}},{{order_id}}) and conditional rendering, supporting version history rollback. - Analytics Dashboard: Visual delivery metrics including deliverability, open rates, click-through rates, and bounce rates, filterable by time range, domain, and email type.
Limitations
- Free Plan Restrictions: Limited to 1 team seat, 1 sending domain, and 500 emails per day — multi-domain or multi-user scenarios require a paid plan.
- Fewer Advanced Features: Compared to SendGrid and Mailgun, MailerSend lacks A/B testing, advanced automation workflows, and dynamic segmentation for marketing campaigns.
- Limited Asia-Pacific Coverage: Infrastructure is primarily in Europe and North America, potentially causing higher latency for users in Asia. APAC customers may benefit from a local SMTP relay.
Use Cases
- Developer Prototyping & MVP Validation (★★★★★): Generous free tier and clear API docs make it perfect for quickly building email notification prototypes.
- Small to Medium Transactional Email (★★★★): Excellent value for under 50,000 monthly sends — verification, order confirmation, password reset workflows.
- Marketing Email (★★★): Basic features suffice for small newsletters, but lack of A/B testing and advanced automation limits campaign effectiveness.
Pricing
| Plan | Monthly Sends | Monthly Price (USD) | Key Features |
|---|---|---|---|
| Free | 12,000 | $0 | 1 seat, 1 domain, API/SMTP |
| Growth | 50,000 | $14.99 | 5 seats, 5 domains, advanced analytics |
| Professional | 100,000 | $34.99 | 20 seats, unlimited domains, priority support |
| Enterprise | Custom | Contact Sales | SLA, dedicated IP, custom integration |
FAQ
How often does the free tier reset? Every calendar month. Unused credits do not roll over. Plan your sending volume accordingly. See Transactional Email API Guide to plan volume.
Does MailerSend support custom sending domains? Yes. Configure SPF, DKIM, and DMARC DNS records. The free plan is limited to 1 sending domain. See Email Deliverability Guide.
How do I migrate from another email service to MailerSend? Switch via SMTP credentials or API key without code changes. Contact support for bulk template migration assistance. See Email Service Setup Guide to switch configuration.