Justification and Examination of Transportation Staff's Executive Travel Costs Act of 2023 or the JETSET Costs Act of 2023 This bill restricts the use of Department of Transportation (DOT) aircraft by the Secretary of Transportation and the Secretary's executive staff. Specifically, the bill prohibits the Secretary and the Secretary's executive staff from traveling on a DOT aircraft unless it is determined that the cost of the flight is at least 5% less than the cost of a flight on a commercial airline. A DOT aircraft is any aircraft owned, operated, or maintained by DOT. This restriction does not apply when emergency travel is required and commercial service is unavailable. The DOT Office of Inspector General (OIG) and Congress must be notified in writing within seven days after such emergency travel is completed. Further, the Federal Aviation Administration must revise Order 2500.36N ( Application of Flight Hour Rates ) to reflect the true cost of flight operations. When calculating per-seat costs of a flight, DOT (1) may not charge different rates to non-DOT officials, and (2) must use the actual and full cost of a flight on a DOT aircraft when comparing such flight to any commercial alternative. DOT's OIG must submit an annual report to Congress that includes an itemization and justification of each trip and flight in which the Secretary or the Secretary's executive staff traveled on a DOT aircraft. The bill also prohibits the Secretary or the Secretary's executive staff from traveling on a DOT aircraft for any trip that involves personal or political activities.