Postmark __full__ Jun 2026
Starting December 24, 2025, the U.S. Postal Service (USPS) implemented significant changes to how postmarks are applied.
To prevent spoofing and ensure delivery to major providers like Gmail and Yahoo, the service authenticates emails using unique DKIM records , SPF , and DMARC SPF alignment .
Sign up at postmarkapp.com to start on the free developer tier, which includes 100 emails per month.
Postmark was built for developers. Integrating it into your stack is straightforward with several Official Libraries for: Node.js PHP .NET WordPress postmark
Why? Because the postmark triggers a psychological shift.
Applied manually by a postal worker using a rubber or metal stamp and an ink pad. Hand cancellations are used for fragile envelopes, oddly shaped packages, and mail brought directly to the counter by philatelists (stamp collectors) who request a clean, crisp mark. 2. Machine Cancellations
—the automated, one-to-one messages like password resets and receipts that must arrive instantly. 1. Getting Started (Setup in 5 Minutes) Create an Account : Sign up at Starting December 24, 2025, the U
Spreading awareness about diseases, sanitation, and safety protocols.
For businesses sending invoices, legal notices, or certified documents, the postmark serves as a receipt of dispatch. The USPS offers "Postmarked Proof of Mailing" services, but even a standard postmark can hold up in small claims court as evidence that a letter was sent on a specific day.
In the 21st century, the word "Postmark" took on a new, digital life. is a leading cloud-based email delivery service designed specifically for sending transactional emails . These are the automated, one-to-one emails that web applications send, such as password resets, order confirmations, shipping notifications, and welcome messages. Sign up at postmarkapp
There are several types of postmarks, including:
We will likely see a hybrid future: A physical envelope with a QR code that, when scanned, reveals a digital timestamp and the exact route of the letter. Yet, for weddings, tax attorneys, and stamp collectors, nothing will ever replace the romantic thwack of a steel die hitting wet ink.
For over two centuries, postmarking remained a labor-intensive, manual process. Postal clerks struck every single letter by hand using wooden or metal handstamps dipped in oil-based ink.
Today, these functions are often combined. A modern postmark frequently serves as both an informational date-and-location stamp and the cancellation that invalidates the stamp, leading to the terms being used interchangeably. Postmarks can be applied by handstamp or machine, using methods ranging from rollers to inkjets, with representing the latest innovation.