Featured Updates
08/31/2023
New Geospatial Products are Available on the Newly Created “Beyond The Mail” page on PostalPro
USPS is excited to announce a new suite of Addressing and Geospatial data services that provide insights on Postal locations, infrastructure, population migration patterns, vacancy trends, emerging roads, and ZIP Code Boundaries The data is available in multiple formats and by subscription that provides regular or frequent refreshes.
08/17/2023
First-Class Mail and Marketing Mail Growth Incentives FAQs
On August 11, 2023, the U.S. Postal Service filed notice with the Postal Regulatory Commission (PRC) requesting approval to make certain Mail Classification Schedule (MCS) changes to establish two Mail growth incentives — a First Class Mail Growth Incentive and a Marketing Mail Growth Incentive.
08/15/2023
January 2024 Price Change Release Overview
Mail Dat Client update is mandatory for this Release.
08/23/2023
Marriage Mail Incentive Fact Sheet
Marriage Mail is a form of direct mail in which marketing service companies combine or “marry” advertisements (e.g., coupons or sales notices) from multiple companies into one mail piece to reduce the cost of the mailing for individual advertisers.
06/30/2023
02/13/2023
Caller/Reserve Transition to the Enterprise Payment System (EPS)
Effective July 1, 2023, customers without an EPS account will no longer be able to apply for or renew caller and reserve services at the retail counter.
Certified Full-Service Vendor Detailed List
This document contains a spreadsheet of detailed contact list information for Full-Service vendors.
08/21/2023
Intelligent Mail Matrix Barcode (IMmb) Technical Specifications
Shipping labels on irregularly-shaped packages, softpacks, and polybags can easily become distorted or creased during automated parcel processing making reading the traditional, linear IMpb barcode challenging to scan. USPS has developed the IMmb to help overcome these challenges and improve package visibility. IMmb barcodes contain the same data as is in the IMpb barcode; however, they use a more robust, space-efficient robust barcode symbology for encodation. The smaller barcode footprint allows two IMmb barcodes to be added within unused areas of existing standard shipping labels. The result is redundancy of the barcode data giving sorters two additional chances to read the barcode.
08/18/2022
Seamless Acceptance Undocumented Mail Fact Sheet
Provides insight into the source of undocumented error reporting, common causes, and best practices.
06/03/2022
New Mailing Standards for the Separation of Hazardous Materials
The Postal Service has issued an interim final rule that will become effective upon publication in the Federal Register on June 6, 2022, with new requirements for the separation of hazardous materials (HAZMAT).
04/07/2022
Balance Check in the Customer Validation Tool Instructions
When given explicit permission by permit holders to do so, MSPs have the ability to perform balance checks for EPS and Local Trust accounts at the permit level.
03/04/2022
Informational Video for Shippers
This video provides helpful information for shippers and includes important USPS parcel shipping requirements.
06/01/2023
Publication for Streamlined Mail Acceptance for Letters and Flats (Pub 685)
Streamlined Mail Acceptance for Letters and Flats (Pub 685) contains the policies and processes for the verification of eligible business mailings using tools provided by Intelligent Mail® Full-Service, eInduction, and Seamless Acceptance.
07/14/2022
11/18/2021
CRID Management
Customer Registration ID (CRID) Overview.
03/23/2021
Latest Updates
09/25/2023
CASS™ Technical Guide for Cycle O
This document provides a technical guide for the CASS™ product. The CASS certification process is designed in cooperation with the mailing industry to improve the accuracy and deliverability of addresses for mail qualifying for postal discounts.
09/25/2023
09/25/2023
09/25/2023
MASS™ Technical Guide for Cycle O
This document provides a technical guide for MASS™ Cycle O. MASS™ is an extension of the CASS™ system.
09/25/2023
PostalOne! Contingency Plan
Learn what to do in the event a system outage prevents you from submitting your mailing information electronically.
USPS Service Alerts
Receive near real-time notifications about postal facility service disruptions due to weather-related outages and other natural disasters or events.
Stay Informed About Postal Policy
Updated daily, the Federal Register Notices offer detailed information regarding official USPS policy and regulatory changes.
Intelligent Mail: Featured Resources

Publication for Streamlined Mail Acceptance for Letters and Flats (Pub 685)
Streamlined Mail Acceptance for Letters and Flats (Pub 685) contains the policies and processes for the verification of eligible business mailings using tools provided by Intelligent Mail® Full-Service, eInduction, and Seamless Acceptance.