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Introducing: IMpb ACS™
Parcel shippers that apply the Intelligent Mail® Package barcode to their parcels now have an option to request ACS notices via the barcode. IMpb ACS™ is available for First-Class Mail®, Priority Mail®, Periodicals, Standard Mail®, Parcel Select® (including Parcel Select® Lightweight), Package Services, Bound Printed Matter, and Standard Post mail pieces. IMpb ACS requires the Mailer ID (MID) used in the Intelligent Mail® Package barcode to be

registered with the USPS ACS department.

  • Complete the ACS Enrollment form to register the Mailer ID for IMpb ACS
  • Print the appropriate ancillary service endorsement on the mail piece (except Periodicals)
  • ACS notices are available to the mailer within 24 hours of receipt at National Customer Service Center
  • Daily fulfillment via a SingleSource ACS fulfillment account provides a daily download from Electronic Product Fulfillment website.
  • Detailed fulfillment shipping notices and invoices are provided.

More information is available in the IMpb ACS Technical Guide.  For information about SingleSource ACS fulfillment, refer to the SingleSource ACS Technical Guide.

SingleSource ACS™
SingleSource ACS is the alternative ACS record fulfillment process now available for ACS customers. With SingleSource ACS, all of the electronic change-of-address and undeliverable (Nixie) mail notices are combined into a single file format and provided via the Electronic Product Fulfillment (EPF) website.

  • Full Service ACS, OneCode ACS, Traditional ACS and the new IMpb ACS are eligible
  • Improved monthly invoicing process
  • ACS notices are available to the mailer within 24 hours of receipt
  • Full Service qualified ACS notices are provided at no charge
  • Daily download from Electronic Product Fulfillment (EPF) web site

See the SingleSource ACS Technical Guide for more details.

ACS Service
ACS is a post mailing service that allows mailers to receive change-of-address (COA) and other reasons for non-delivery electronically and reduce the number of manual (hardcopy) address notifications.

ACS has many benefits over manual address corrections

ACS is a cost-effective, efficient means of obtaining accurate COA or reasons for non-delivery information. Utilizing ACS can:

  1. Reduce manual address costs.
  2. Reduce labor-intensive address change functions by eliminating returned mail.
  3. Choose when to receive fulfillment of time-sensitive information on a daily, weekly, or monthly schedule.
  4. Retrieve address change information electronically via a secure Internet site to allow automated updating of mailing lists.
  5. Receive notifications that relate specifically to their address files.

ACS has four distinct implementation methods which offer several different options:

  1. OneCode ACS Technical Guide contains information to participate in OneCode ACS®. (uses IM® barcode)
  2. Traditional ACS Technical Guide contains information to participate in Traditional ACS®.
  3. Full Service ACS, which is currently provided as an additional benefit for mail that qualifies for Full Service discount postage prices. (uses IM® barcode)
  4. IMpb ACS Technical Guide contains information to participate in IMpb ACS. (uses IM® package barcode)

To participate in ACS, mailers must modify their mailing label, address block, and mailpiece according to the requirements associated to the specific ACS service they are applying for.

As ACS-modified mailpieces are processed via Postal Automation Redirection System (PARS) or Computerized Forwarding System (CFS), ACS notifications are generated when possible. However, ACS is an enhancement to the traditional process of manual (hard copy) notifications and it does not completely replace or eliminate hard copy address change notifications.

The ACS notifications are transmitted to the National Customer Support Center (NCSC), where the notifications are consolidated into a file for the mailer. ACS fulfillment options vary depending on specific ACS service you are applying for.

Which ACS service should you use?
This is ultimately a decision your company will have to make. However, the USPS® is currently implementing the Intelligent Mail® Barcode as a requirement to receive postage discounts. The OneCode ACS Technical Guide can also be used to assist Full Service mailers with the design of their mail piece so they can receive Full Service ACS benefits. For more information on how to qualify for Full Service discounts and benefits, refer to the Intelligent Mail RIBBS link for the Guide to Intelligent Mail for Letters and Flats.

While the ACS Department can assist you with your questions, it is very beneficial for all customers to read the specific ACS service documentation and consolidate the questions. You may email the questions and schedule conference calls utilizing the Contact Information below:

Contact Information:

  • ACS Department
  • Phone: 877-640-0724, option 1
  • Email: acs@usps.gov
  • Page updated: 02/24/2014
Important Updates

The "Heartbleed" bug hasn't affected Postal Service websites that require customers to provide usernames and passwords, according to USPS IT and the Corporate Information Security Office (CISO). To learn more information, click here.

Standard Mail DSCF Load Leveling Final Rule Published in the Federal Register

The Postal Service has released its Federal Register final rule revising the service standards for Standard Mail that is eligible for Destination Sectional Center Facility (DSCF) rates. These changes will allow a more balanced distribution of DSCF Standard Mail across delivery days. With its new rules, USPS is extending delivery expectation to four days for mail entered on Friday and Saturday. National Implementation began April 10, 2014.

January 2014 Price Change Fact Sheets

Getting Started with Full-Service Intelligent Mail

PostalOne! Contingency Plan

For mailers unable to submit electronic information, click here for the PostalOne! Contingency Plan.


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