Top Secret material may only be transmitted by very limited, tightly controlled methods such as direct hand-to-hand transfer between appropriately cleared personnel and specially authorized secure communication systems; regular mail or ordinary commercial delivery services are not permitted for this level of information.

Core authorized methods

  • Direct contact between appropriately cleared persons, where the sender personally hands the Top Secret material to a recipient who holds the required clearance and need-to-know, following all required accountability procedures (e.g., receipts, secure packaging, and control logs).
  • Use of an authorized cryptographic system or secure communications circuit (for voice, data, message, or fax) that has been formally approved for Top Secret transmission, such as those accredited under national communications security standards.
  • Use of a designated courier or messenger system specifically created or certified for Top Secret material, such as a defense or diplomatic courier service or a specially designated courier operating under strict regulatory guidance for Top Secret transport.

Methods that are not acceptable

  • Standard commercial delivery services (e.g., non‑cleared carriers or generic courier companies) may not be used for Top Secret material, even if sealed and tracked, because they lack the necessary clearance, control, and cryptographic protections.
  • Ordinary postal services (including registered or certified mail) that are sometimes allowed for Secret or Confidential material are not authorized for Top Secret, which requires the higher protections listed above.

Typical “select all that apply” style answer

When faced with a multiple‑choice question like “Which of the following methods may be used to transmit Top Secret material?”, the correct options generally correspond to:

  • Appropriately cleared courier or designated secure messenger.
  • Protected/secure facsimile, message, data, or voice over an authorized Top Secret‑accredited cryptographic or secure communications system.

Any options listing routine commercial delivery or standard postal services, even if described as registered or tracked, would normally be incorrect for Top Secret material.

Information gathered from public forums or data available on the internet and portrayed here.