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Domestic Classes of Mail

The cost of mailing varies with each classification.

First-class, Standard Class and International Letter Class Mail weighing one ounce or less is nonstandard* if it exceeds any of the following size standard limits:

11 1/2" in length, 6 1/8" in height, 1/4" in thickness
or:
Its aspect ratio (length divided by height) does not fall between 1 to 1.3 and 1 to 2.5 inclusive.

* There is an additional postage charge on each piece of mail that is found to be nonstandard.

In addition, pieces which are less than the following dimensions are non-mailable in the U.S. Postal Service and will be returned to you:

3 1/2" in height, 5" in length or .007" in thickness (thickness of a postcard)

First-class Mail

All mailable matter may be mailed as First-class Mail, Priority Mail, or Express Mail. The following examples are considered First-class matter and must carry postage at First-class Mail, Priority Mail, or Express Mail rates.

  • Matter wholly or partially handwritten or type-written, except authorized additions to Periodicals or Standard Mail and written or type written matter in Library and Special Standard Mail as permitted by the corresponding standards, originals or carbons, invoices (except when accompanying the matter to which they relate); postal cards, post cards and letters bearing a written date when that date is not the date of mailing.
  • Bills and statements of account, regardless of method of preparation or quantity of identical pieces mailed, except authorized enclosures in or attachments to Standard A or B class mail.

If you are not sure if it is First-class, ask us!

Priority Mail

All First-class mail exceeding 13 ounces and not exceeding 70 pounds is considered priority mail and, at the option of the mailer, any mail weighing 13 ounces or less. There is no minimum weight limitation.

  • Use Priority Mail when 2 to 3 day service is desired. There is no guarantee.

NOTE: When using Priority Mail, we recommend use of priority envelopes, available at no charge, from Mail Services.

Standard Mail

The following is considered Standard Mail Matter:

  • Circulars - Catalogs
  • Booklets - Newsletters
  • Merchandise - Product Samples
  • Photographs - Printed Matter

Reduced rates are available for mailing 200 or more like pieces.

Special Services

Accountable Mail includes all Certified, Registered, Insured and Express Mail.


Certified Mail - Provides you with a mailing receipt and a record of delivery is maintained at the recipient's post office for two years. Certified mail service is available only for First-class Mail. No insurance coverage is provided.

Registered Mail - The registered mail system is designed to provide added protection for valuable mail. Postage insurance may be purchased to cover articles valued up to $25,000. Registered mail is the most secure mail the Postal Service offers. It incorporates a system of receipts to monitor registered articles from the point of acceptance to delivery. Added security may delay delivery by 24 - 48 hours. Do not use plastic tape on Registered Mail. All seams must be covered by a paper type surface so the seams can be hand-stamped to show if the parcel has maintained its integrity against tampering. Paper backed tape is okay. Mail Services will do this for you.

Insured Mail - You can obtain payment for domestic mail that has been lost, rifled or damaged by having it insured. You can buy insurance up to $5000.

Return Receipts - A return receipt is your proof of delivery. It is available for insured mail, certified, registered, and domestic Express mail shipments. The return receipt identifies the article number, who signed for it and the date it was delivered. It is not necessary to utilize a return receipt on all certified or registered mailings. Return Receipt may be an unnecessary expense. The Postal Service keeps a two year record for delivery of special services mail. Call us if you're considering the need.

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