Mail Classifications | Texas Tech University Health Sciences Center
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USPS Mailing Services


First Class Mail

First class is used for normal correspondence.  The advantages of first class are faster delivery times, free forwarding or return of undeliverable items, and the ability to be sealed against inspection.

Priority Mail

All first class mail is eligible to be mailed Priority. First class mail weighing over 13 ounces automatically upgrades to Priority mail. Priority mail is best known as the 1-3 day service. Delivery averages 2-3 days but is not guaranteed.  Special Priority packaging for letters and packages is available from Mail Services.

Express Mail

Express Mail is the overnight delivery service available from the U.S. Postal Service.  Express Mail packages may be tracked to verify date and time of delivery.  Unless waived by the sender, all Express Mail items must be signed for by the recipient.  Although all zip codes are not guaranteed for overnight delivery, full refund of postage is available from the USPS if the item is not delivered within its guaranteed time. Check overnight availability.  The package insurance of $500.00 is provided with the cost of Express Mail for the reconstruction of lost or damaged documents.  The Postal Service's liability for negotiable currency is limited to $15.00.

Standard Mail

Standard Mail is mail weighing 16 ounces or less. Most large mailings of 200 pieces or more are eligible for marketing mail. Marketing mail usually consists of printed matter such as newsletters, booklets, and catalogs. It is a less expensive rate, but forwarding or return of undeliverable items will be charged at first class rates by the US Postal Service. All pieces in the mailing must be of the same weight and content. Contact Automation Bulk Mail for more information or questions.

Retail Ground (Formerly Parcel Post)

Retail Ground is matter weighing 16 ounces or more. Retail Ground is divided into special rate groups for library mail, media mail and parcels. Each piece of retail ground mail must meet eligibility requirements and weigh less than 70 lbs.

International Mail

Most items are eligible to be mailed to foreign countries, however there are restrictions that vary by country. Letters, documents, and printed matter can be mailed internationally without customs documentation if they weigh less than 16 ounces.  Any item weighing 16 ounces or more must bear the appropriate signed customs forms or it will be returned to the sender by the U.S. Postal Service. Please contact Mail Services for restrictions and for the correct customs forms.  International mail may be sent by air or economy (surface) rates.  Airmail is generally delivered within 7-10 days. Economy (surface) rate mail can take up to 4 weeks for delivery.

Business Reply Mail

Business Reply Mail (BRM) enables departments to pay for return postage when requesting a reply from correspondents. The reply can be in the form of envelopes, cards, labels or detachable self-mailers and the department pays postage only on the pieces returned to the department.  HSC Mail Services maintains a BRM permit and account with the U.S. Postal Service.  The USPS charges a small accounting fee per piece. If you wish to use BRM, please contact Mail Services or the HSC Printing Center to have your mail piece properly designed.

Courtesy Reply Mail

Courtesy Reply Mail (CRM) is used when the sender wants to enclose a return envelope, but does not wish to pay the return postage.  Most often used for bill payments, subscription renewals, RSVP, etc.  CRM is First class Mail and generally faster than plain envelopes and postcards.  Automation compatible envelopes can be designed by the HSC Printing Center.

Postage Due Mail

HSC Mail Services maintains a postage due account with the U.S. Postal Service to cover insufficient postage on any mail piece addressed to TTUHSC departments.  Mail pieces addressed to any HSC department that bears insufficient postage will be billed to that department plus a .20 cent accounting fee per piece.



Size Dimensions



Each card mailed as a postcard must be rectangular in shape. Minimum size is 3.5 inches high, 5 inches wide and 0.007 inches thick. Maximum size is 4.25 inches high, 6 inches long and 0.0095 inches thick. Double or folded cards must be mailed at letter rates.

Letter Mail

Minimum size for a letter is 5 inches long, 3.5 inches high, and 0.007 inch thick. Maximum size is 11.5 inches long, 6.125 inches high, and 0.25 inches thick.

Letter envelopes eclipsing these dimensions and weighing 1 ounce or less are charged an additional $0.12 oversize fee.

Flat Mail (Larger Envelopes)

Minimum size is 11.5 inches long, 6.125 inches high and 0.25 inches thick. Maximum size is 15 inches long, 12 inches high and 0.75 inches thick.


Maximum weight is 70 lbs. The length and girth of packages combined mailed through the US Postal Service cannot exceed 108 inches.

Any item larger than the maximum flat size is considered a parcel.

Additional Services


Certified Mail

Need evidence of mailing? - Certified mail gives the sender evidence of mailing with a dated mailing receipt. It provides a confirmation number to confirm the date and time of delivery or attempted delivery. Delivery is recorded by the U.S. Postal Service. You can confirm delivery at No insurance coverage is provided with this service. This service can be applied to First-Class and Priority Mail. For an additional fee, Certified Mail may be combined with a Return Receipt, providing the sender with evidence of delivery with a signature. International and Express Mail cannot be certified.


Return Receipt

Need evidence of delivery - A return receipt can be added to Certified Mail to provide the mailer with evidence of delivery. The Return Receipt card must be completed by the mailer and attached to the article at the time of mailing.


Delivery Confirmation

Need to know when your mail arrived? - Delivery confirmation provides a confirmation number to confirm the date, time and zip code of delivery or attempted delivery. Confirm delivery at


Signature Confirmation

Need to know who accepted your mail? - All the benefits of Delivery Confirmation plus a signature. Signature confirmation provides a confirmation number to confirm the date, time and location of delivery or attempted delivery. A signature will be required from the person who accepts your package. You can request to have a letter faxed or mailed to you with a copy of the recipient's signature. Confirm delivery at


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