Postal Service:

Processing of ZIP + 4 Letters Receiving Postage Discounts

GGD-88-5: Published: Oct 16, 1987. Publicly Released: Oct 16, 1987.

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In response to a congressional request, GAO reviewed the U.S. Postal Service's (USPS) processing of letters that receive a ZIP + 4 postage discount, to determine the amount of: (1) discounted mail the automated equipment bypassed or rejected; and (2) revenue USPS lost in the form of discounts on such mail.

GAO found that: (1) of the 5 billion discounted letters USPS received over an 18-month period, it processed only 10 percent automatically to carrier routes because many mail processing centers did not have automated sorting equipment; (2) although USPS plans to automate about 215 centers nationwide, it automated only 130 during fiscal year 1986; (3) 90 percent of the 5 billion letters received the 5-cent discount and the remaining 10 percent received the 9-cent discount; (4) USPS discounted $25 million in mail that it did not automatically sort; and (5) although the 130 centers were responsible for carrier-route sorting 43 percent of the 5 billion letters, they automatically sorted only about 23 percent. GAO also found that some letters never reached the bar code sorters because: (1) optical character readers rejected letters as unreadable; (2) the number of letters going to some delivery zones was too small to justify the use of sorters; (3) there was not enough time to use the sorters; and (4) many centers did not have procedures for capturing all locally destined letters in place.

Recommendation for Executive Action

  1. Status: Closed - Implemented

    Comments: USPS will periodically count ZIP + 4 mail to more fully utilize automated mail processing equipment.

    Recommendation: The Postmaster General should direct Division Managers/Postmasters to periodically count the amount of ZIP + 4 mail that automated mail processing centers are receiving at all entry points to increase the volume of ZIP + 4 mail receiving automated processing to carrier routes.

    Agency Affected: United States Postal Service


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