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The Mailer Identifier (MID) is a field within the Intelligent Mail barcode that is used to identify mailers. MIDs are assigned by the USPS® to a Mail Owner, Mailing Agent or other service providers who request them.

MIDs are either a 9-digit or a 6-digit numeric code and are assigned based on annual mail volume criteria. One 9-digit MID is assigned to a business location without a volume requirement.

How to obtain a Mailer ID
To request a Mailer ID (MID) go to http://www.usps.com/ and select the Business Customer Gateway located on the

bottom right hand corner of the web page footer. You must either be an existing or a registered user, or can sign-up as a new user for a business account to gain access to the Business Customer Gateway. Once you have access, request the "Mailer ID" tool and proceed with the "Request a MID" button to obtain a MID.

Exception Process
If you need additional MIDs, not obtainable through the Business Customer Gateway-MID Tool, refer to the Mailer ID Exception Process. Mailing Agents who are authorized to obtain MIDs on behalf of Mail Owners, should refer to the Agent Application Process. All forms can be viewed and printed from the Important Links box on this web page. Complete the Mailer ID Application and the Additional Accounts Information sheet if applicable and submit them to the Business Mail Entry Unit (BMEU) or the Mailpiece Design Analyst for processing.

To locate your local Business Mail Entry Unit (BMEU) or Mailpiece Design Analyst (MDA), go to the following URLs:
www.usps.com/nationalpremieraccounts/findlocators.htm (BMEU locator)
https://ribbs.usps.gov/mda/mda.cfm (MDA look-up tool)

Program Registration Mailer ID Assignment
For shippers who enroll in Shipping Service programs using the Business Customer Gateway, one 9-digit (master) Mailer ID is initially assigned. Subsequent 9-digits are assigned based on a Mail Owner single business or a mail service provider's single-client business shipping location.

Contact Information:

Important Updates

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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