Technical Errors Caused Revenue Loss
Introduction
This management alert presents the issues the U.S. Postal Service Office of Inspector General (OIG) identified during the Effectiveness of Package Verification Solutions audit (Project Number 25-130). Our objective is to provide immediate notification of these issues.
Background
The Postal Service uses two key systems to scan packages and verify that shippers paid the accurate price. Its Automated Package Verification (APV) system identifies insufficient postage by comparing shippers’ reported package measurements against measurements captured on Postal Service processing equipment, charging any additional postage due, and refunding overpayments. Since it was introduced in 2017, APV has increased Postal Service postage collection by $1.1 billion. The Postal Service also uses Product Tracking and Reporting (PTR) to track machine scans. PTR contains tracking data for each package, including machine names and measurements.
The Postal Service has several types of machines in its network that can capture package measurements. Generally, APV compares measurements collected on different machines across the network to determine which are the most “trusted” or precise. To be trusted, the machine must be on the Postal Service’s programmed list of machines that it has tested and considers capable of producing accurate measurements.
A key machine, which processed approximately 49 percent of packages in mail processing facilities from October through December 2025, is the Automated Parcel Bundle Sorter (APBS) (see Figure 1). These machines produced about 62 percent of all trusted weights and 18 percent of all trusted dimensions for the Postal Service. Formerly, this machine was known as the Small Parcel and Bundle Sorter, and it was labelled as SPBSTS (Small Parcel Bundle Sorter Tracking System) in the Postal Service’s systems and corresponding data. In 2011, it was upgraded to improve operational capabilities and was renamed the APBS.