LetterStream’s API allows companies to automate business-critical mail.
Behind every successful operations team is one core truth: they didn’t get there by printing and stuffing envelopes by hand.
Automation has become the backbone of modern business operations, especially for teams managing recurring or high-volume mail. And if you’ve ever wished you could hit “send” on a document and have it magically turn into trackable Certified Mail or just a First-Class letter… you’re closer than you think.
With the LetterStream API, developers and operations leaders can fully automate the printing, processing, and sending of snail mail, securely and efficiently.
Here are five real-world use cases that show how the LetterStream API saves time, reduces stress, and helps teams work smarter (not harder).
1. Automate Late Payment Notices from Your CRM
Still sending out manual past-due letters? With the LetterStream API, you can connect your CRM or billing platform to automatically trigger a physical notice after a set number of days.
Let’s say a customer hasn’t paid within 30 days. Your system can generate a PDF notice, ping the LetterStream API, and send the letter via First-Class Mail—without anyone printing or folding a thing.
Need to add Certified Mail for legal protection? You can include that logic too. Tracking numbers, digital proofs, and delivery data all included.
This is how finance and AR teams turn chaos into consistency.
2. Trigger Mailings from Your Internal Software
Whether you’re using custom ERP tools, a ticketing system, or something built in-house, if it can send a webhook or make an HTTP request, it can send mail through LetterStream.
Imagine this:
- An eviction notice is triggered when a resident’s file status changes
- A violation letter goes out when a photo is uploaded in your HOA software
- A legal firm’s case management system auto-generates and sends a filing notification
If you’ve got software that manages workflows, you’ve got the power to connect it directly to our print and mail software—and make the paper part disappear.
3. Bulk Job Scheduling and Batch Mail
Need to send 500 notices each Friday? Or maybe you’re processing thousands of monthly statements for clients?
With the LetterStream API, you can script and schedule batch jobs that send all your mail at once, pulling from databases, applying templates, and routing based on zip code or content.
You stay in control, and your team avoids the last-minute, end-of-month stress. Plus, you’ll always have a full audit trail to reference, including file uploads, job IDs, and delivery confirmations.
Pair this with StreamLogic™, and you can build in automated logic to handle special rules, like Certified Mail for certain states or alternate return addresses for specific regions.
4. Empower Your Customers
If your business offers SaaS tools to other companies—think property management platforms, legal software, or fintech tools—you can integrate the LetterStream API directly into your platform.
That means your users can send Certified Mail or First-Class Mail without ever leaving your website.
You get:
- Embedded mailing capabilities
- Brand consistency (you can white-label the experience)
- Zero support tickets about printers or postage
We handle the print, insert, and send. Your platform gets the credit. Everybody wins.
5. Create a Compliance-First Mailing System
If your industry deals with HIPAA, legal timelines, or regulatory disclosures, the API allows you to bake secure, traceable mail delivery into your compliance workflows.
No more guessing if something was sent. No more “we thought the admin handled that.”
Every job has a digital record, every piece of Certified Mail is trackable, and you can see when it was mailed from our end.
For healthcare groups, law firms, and insurance providers, this turns compliance from a risk into a repeatable system.
Let Your Systems Do the Sending
The best part? Your team can stop wrestling with stamps and focus on work that actually moves the business forward.
When physical mail becomes just another API call, everything gets smoother: timelines, compliance, customer experience, and morale.
Learn more about LetterStream’s API, here.
LetterStream offers bulk printing and mailing services, allowing companies to send physical mail online. Whether it’s online Certified Mail, First-Class Mail, FedEx 2Day, or postcards, we give both small businesses and large corporations that time and freedom back to work on tasks that better serve the company. If you’re interested in creating a free account, you can do so here.
