Postal Services
Skip to main contentDiGiorgio Campus Center Lower Level, Rock Hill, SC  29733  •  803/323-2293   

Who's Who in the Post Office

Student Information

Transaction Times and Route Schedule

Preparation for Departmental Pick-Up

Personal Mail Policy

Intra-Campus Mail

Metered Mail

What Are You Mailing

Choosing a Service for Mailing

Adding Extra Services

Addressing Your Mailing

Service Endorsements Reference Chart

Preparing Packages for Mailing

Correct State Abbreviations for Mailing

US Postal Service Rates Chart for Postage

Standard Mailing Preparation

Standard Mailing Preparation


  • Mailing must be a minimum of 200 pieces.
  • Mailing must have 128 permit indicia in upper right hand corner of the address side of the mail piece.
  • Mail must be in zip code order from lowest to highest zip code.  Any zip code containing 150 pieces or more must be banded together and have the exact number of pieces attached to the bundle.  No other separation is needed.
  • A report must accompany the mailing showing the number of pieces in each zip code and conclude with the total number of pieces in the mailing.
  • Mailing cannot be offering anything for sale, such as tickets or fees.
  • Not to be used for time sensitive mailing, a maximum of 3 days is requested for processing at the Winthrop Post Office, and the US Postal service allows itself from 2-9 days for delivery. In most cases the mailing is delivered in 2-4 days, but standard mail receives the lowest handling priority.
  • A Service endorsement must appear on each piece.  Refer to Service Endorsement Reference Chart for examples.  The most commonly used at Winthrop is forwarding service requested or address service requested. Please refer to “Service Endorsement Reference Chart” offered on this web site for further information.


This is the preferred and easiest way to prepare your mailing for standard mail.
To meet the requirement for machinable mail, your mailing must be either a post card, in a sealed envelope, or if folded paper tabs at each end of the mail piece sealing all loose sheets together.

Designing Letters and Cards for Automated Processing

Characteristics and Content

Minimum: 3-1/2 inches high, 5 inches long, and 0.007
Maximum for cards at card rate 4-1/4 inches high, 6 inches long and 0.016 inch
Maximum for letters and other cards: 6-1/8 inches high, 11-1/2 inches long,
¼ inch thick.

Maximum Weight:
Standard mail Machinable 3.5 ounces.

Clasps, strings, stables, buttons, or protrusions that might impede or damage the
mail or mail processing equipment.

Other Machinablity Standards:
Regular shape, with adequate flexibility and rigidity.
Tabbing for self-mailers or pieces with open edges.

To be sure a mailing qualifies, please don’t hesitate to bring us a sample copy, and if necessary, we will verify acceptability with our contact at the Rock Hill PO.

Non-Machinable Mail

Flats include mail that is oversized for letter mail. Flats receiving discount rate must now be addressed in portrait mode as opposed to the traditional landscape mode.  This is new as of June 2009. Flats must be placed in white mail tubs obtained from our office. Each Zip Code must be rubber banded together, unless one zip code fills the bucket. A report must accompany the mailing listing the number of pieces in each zip code. 
All the requirements listed for machinable mail, can be applied to flat mail pieces.

































Please click here to download a PDF file in Abode Acrobat for instruction on how to prepare discount letters and cards. The link will open in a new window. If you do not have Adobe acrobat click the icon below to download it.

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United States Postal Service


Rock Hill, South Carolina   29733
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