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312 Availability

312.1 At Time of Purchase

Customers may purchase a certificate of mailing when sending the following:

  1. Postcards.
  2. Unregistered First-Class Mail International items.
  3. Free matter for the blind.
  4. Unregistered Priority Mail International Flat Rate Envelopes or Small Flat Rate Priced Boxes.
  5. Ordinary (uninsured) Priority Mail International parcels including Medium and Large Flat Rate Boxes.
  6. Airmail M-bags.

312.2 After Mailing (Additional Criteria)

To obtain an additional certificate after mailing, the mailer must present the original certificate and an additional certificate endorsed “Duplicate” or a copy showing the original dates of mailing. The additional certificate must be postmarked to show the current date. A certificate of mailing cannot be obtained in combination with Registered Mail items, insured parcels, or bulk mailings of 200 pieces or more that bear a permit imprint.