What is Delay Code?

IATA delay codes were developed to standardize how airlines report commercial flight departure delays. Previously, airlines each used their own systems, complicating the sharing and aggregation of delay data. To streamline this process, IATA introduced codes that pinpoint the cause and assign responsibility for delays. This standardization aids in aviation administration and logistics, and it also plays a critical role in determining any penalties related to delays. These codes are utilized in movement messages that are sent electronically via SITA from the departure airport to the destination, and they are also used internally by airlines, airports, and ground handling agents.

To reduce the costs associated with aircraft remaining on the ground, airlines strategically plan to minimize ground time. It’s common for airlines and ground handlers to have contracts that use a bonus–malus system, which imposes penalties on the party responsible for causing delays. The delay codes are categorized into nine sets, each represented by either a two-digit number or a two-letter code. While most airlines prefer the numeric system, some opt for the alpha code. However, according to the AHM 780 Aircraft Movement Message specification, only the numeric codes are recommended for use. Some airlines go further, adding an extra character to IATA codes for more detailed delay analysis, although these extensions are not standardized.

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