Features—SMTP

Send via SMTP
or API. Your call.

Use our HTTP API for modern apps or drop in SMTP credentials for any legacy system. Same deliverability, same pricing, zero lock-in.

SMTP that works with everything

Full authentication, tracking, and deliverability out of the box

Quick setup with your project credentials. Works with any email client or application.

TLS/SSL encryption on ports 465 and 587. Your emails are always transmitted securely.

Works with Outlook, Thunderbird, Apple Mail, or any SMTP-compatible application.

Automatic verification that your sender domain is verified before accepting emails.

Attachments, custom headers, HTML emails, and multiple recipients.

SMTP emails use the same reliable delivery infrastructure as API emails with full tracking.

Choose the right option for your use case

Feature	Traditional SMTP	Plunk SMTP	Plunk API
Protocol	SMTP	SMTP	HTTP/REST
Setup Complexity	Medium	Easy	Easy
Tracking & Analytics	✗	✓	✓
Works with Email Clients	✓	✓	✗
Domain Verification	Manual	Automatic	Automatic
Attachments	✓	✓	✓
Template Support	✗	✗	✓
Workflow Automation	✗	✗	✓

Recommendation: Use the API for modern applications with workflow automation. Use SMTP for email clients and legacy systems.

Perfect for these scenarios

01
Legacy System Integration
Already have applications using SMTP? No need to rewrite code. Just swap your SMTP credentials and keep everything else the same.
→ Zero code changes required
02
Email Client Sending
Marketing teams can send emails directly from Outlook, Thunderbird, or Apple Mail using familiar tools without learning new APIs.
→ No technical knowledge needed
03
Framework Compatibility
Works with any framework or language that supports SMTP. Perfect for older systems or platforms without HTTP API support.
→ Universal protocol support

Get your SMTP credentials and start sending from any client or application. No credit card required.