API

By Lee Garvey

Most developers can automate email, SMS, and push notifications without breaking a sweat. Physical mail is a different challenge entirely — but a mail automation API eliminates that gap, letting you trigger postal mail the same way you’d fire a webhook or a transactional email.

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Why Developers Are Adding Mail to Their Stacks

Email from unfamiliar senders gets filtered to spam. Physical mail gets opened. For billing notices, legal documents, compliance communications, and customer acquisition, postal mail consistently outperforms digital-only approaches.

The problem has always been the manual effort. As Click2Mail founder and CEO Lee Garvey explains: “Without integration, you’re gonna have to export stuff, you’re gonna have to re-import it somewhere else — that’s a bunch of steps and processes that integration automation does for you automatically.”

When mail is triggered programmatically, that friction disappears entirely. The result is a streamlined mailing workflow that runs without manual input — no printing, no stuffing envelopes, no post office runs.

How the Click2Mail Mail Automation API Works

Click2Mail’s Mailing Online Pro API exposes postal mail functions through REST, REST Batch XML, and SOAP interfaces. It’s designed for developers integrating print-and-mail capabilities into web apps, mobile apps, or mailroom automation systems.

Core API Features

• Automatic address cleansing via CASS and NCOA processing on every submission
• IMb tracking included on every mailpiece at no additional cost
• Tiered production options — one-day, three-day, or seven-day — to balance speed and cost
• No subscription fees and no minimum volume requirements, making it practical for low-volume and high-volume use cases alike

The API supports a wide range of mail formats, including letters, postcards, certified mail, flyers, brochures, EDDM mailers, and Priority Mail. A single integration can handle everything from a welcome letter to a bulk marketing campaign to a legally required notice.

Common Use Cases for Mail API Integration

Transactional Mail

The most common starting point for API integration is transactional mail — documents that need to go out automatically when something happens in your system:

• Invoices and billing statements
• Insurance policy documents
• Appointment reminders
• Password and PIN notifications
• Membership renewal notices

Click2Mail’s MailJack+ application is purpose-built for this use case, automatically reading addresses from pre-addressed PDFs and mailing each document with IMb tracking — no manual steps required.

CRM-Triggered Campaigns

When a contact hits a specific stage in your CRM, mail goes out automatically. Carly Brown, Click2Mail’s customer support manager, describes the experience: “If they can connect to Click2Mail via the CRM hub, it’s a set it and forget it type of thing — you can maintain an ongoing campaign without manually managing each one with a spreadsheet.”

Click2Mail’s CRM Hub currently integrates with Salesforce, Podio, Follow Up Boss, and Google Sheets, with new CRMs typically added within two to four days of a request.

Compliance and Legal Notices

For organizations sending HIPAA-regulated communications, certified mail, or legally required notifications, API integration adds a critical layer of reliability and auditability. Every mailpiece is tracked, and the data comes back to your system automatically — so you always have a record of what was sent and when.

Tracking and Delivery Confirmation Built In

One of the most underrated advantages of API-driven mail is the tracking data that comes back from the USPS. Lee Garvey explains the opportunity this creates: “We give you the data that’s coming back from the postal service so that you can do an integration, you can do it automatically.”

That means you can:

• Know exactly when a mailpiece reaches the recipient’s local post office
• Trigger follow-up actions — a phone call, an email, an SMS — to coincide with delivery
• Maintain audit trails for compliance-sensitive communications

This is the foundation of true multi-channel marketing timing — coordinating physical and digital touchpoints so they land together rather than at random.

The USPS Intelligent Mail Barcode system powers this tracking. You can read more about how IMb works directly on the USPS Business Mail 101 resource.

Integration Options Beyond the Core API

Not every team wants to write custom API code. Click2Mail offers several no-code and low-code integration paths:

• Zapier — connects Click2Mail to hundreds of popular web apps without writing a single line of code. Ready-made Zaps are available for Google Sheets, Google Forms, Wufoo, and more
• Keragon — a HIPAA-compliant automation platform that connects Click2Mail with EHRs, CRMs, intake forms, and billing systems. SOC2 Type II certified with a BAA included on all plans
• Email-to-Mail — if your application can send email, it can trigger physical mail. Attachments are automatically printed and mailed the next business day
• Microsoft Word Add-In and Google Workspace Add-Ons — for teams that want to send mail directly from the tools they already use

For a deeper look at how the USPS handles automated mail processing and what address standardization requirements apply, the USPS Publication 28 on postal addressing standards is a useful technical reference.

Security Considerations for Mail API Integrations

For teams operating under HIPAA or handling sensitive documents, API-driven mail offers a compliance advantage that’s easy to overlook. Carly Brown notes: “With HIPAA, there’s a clean desk policy — you cannot print stuff out at the office and just leave it laying around. Doing it all digitally means employees aren’t printing stuff out, leaving it on the printer. It’s actually a security advantage.”

API integration also means better control over sensitive document delivery, with every mailpiece tracked and logged rather than handed off to an employee with a stamp and a prayer.

Getting Started

If your application already handles transactional email, integrating postal mail with a mail automation API is a natural next step — and the infrastructure is more accessible than most developers expect. Click2Mail’s API is available in REST, REST Batch XML, and SOAP, with a staging environment for testing before you go live.

Ready to add physical mail to your workflow? Explore the Click2Mail API and see how quickly you can have your first automated mailpiece in the queue.