A PNR can contain a maximum of 999 elements. These PNR elements can either be mandatory or optional. The mandatory elements are: LetterDefinitionTransaction Command SSegmentSS MNameNM AContactAP RReceived FromRF TTicketingTK When creating a PNR, you can enter the elements in any order.

A Passenger Name Record (PNR) in a Global Distribution System (GDS) like Amadeus or Sabre can contain a maximum of 999 elements. An "element" refers to any individual piece of data within the booking, such as a name, a flight segment, a phone number, or a special service request (SSR). While most standard bookings only contain 10 to 20 elements, complex corporate itineraries or group bookings with multiple passengers and diverse travel components can approach this limit. There are five mandatory elements required to create a valid PNR, often remembered by the acronym PRINT: Phone, Received From, Itinerary, Name, and Ticketing. Beyond these, optional elements like frequent flyer numbers, seat assignments, and remark fields can be added. It is also worth noting that a single PNR can contain up to 99 segments (individual flights, hotel stays, or car rentals), but once the 999-element threshold is reached, no further data can be added without creating a new record.