When the PRC establishes a docket it assigns it a unique identification tag that indicates the specific proceeding, the nature of the issue being examined, and the fiscal year in which the proceeding began.

The nature of the proceeding is abbreviated by a letter code. For example, “R” stands for a Rate case, and "RM" is a Rulemaking case. The letter code is then followed by the current year and the number of the case for that year. For example the 2nd rate case for FY2009 would be Docket R2009-2. For example, the Docket for the 3rd Rulemaking case of FY2010 would be RM2010-3.

Here are the Docket abbreviations currently in use:

  • “A” – Appeal of a Post Office Closing
  • “ACR” – Annual Compliance Determination (End-of-year Report on Postal Service performance and compliance in meeting its statutory requirements)
  • “C” – Complaint (Complaints on major service or price issues, often with national or systemic implications)
  • “CP” – Competitive Products (Postal Service proposes a rate change for competitive products)
  • "G" - General
  • “IM” – International Mail (Information and correspondence from the Universal Postal Union, UPU)
  • “K” – Contract (using K is legal shorthand)
  • “MC” – Mail Classification
  • “MT” – Market Test (Postal Service request to test market a new postal product)
  • “N” – Substantial change in the Nature of service proposed by the Postal Service requiring an Advisory Opinion by the Commission
  • “PI” – Public Inquiry (For example, a public inquiry was initiated to request public views on universal postal service and the postal monopoly that were instrumental to the development of a Commission report to the President and Congress on this issue)
  • “R” – Rates (Postal Service proposes to change rates for market dominant products)
  • “RM” – Rulemaking
  • "SS" - Special Studies and
  • "T" – Annual Review of Tax calculation