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# IATA and ICAO Airport Codes: What They Mean and How They Differ
- URL: https://roadme.io/blog/airport-iata-icao-codes/
- Published: 2026-10-12T09:32:17.000Z
- Updated: 2026-10-12T09:32:17.000Z
- Author: RoadMe
- Tags: Perspectives

IATA and ICAO codes are two different systems for identifying locations in aviation. Passengers usually encounter three-letter IATA codes in tickets and flight searches. Four-letter ICAO location indicators primarily serve flight operations and professional aviation information.

One airport can have both identifiers. They do not mean different terminals or alternate spellings of one abbreviation: use the appropriate system when comparing or looking them up.

## What an IATA code does

IATA is the International Air Transport Association. Its three-letter location codes support commercial systems, including reservations, ticketing, schedules and baggage handling. A short standard identifier helps distinguish similarly named places across languages.

An IATA location is not necessarily an airport. The system also includes cities and metropolitan areas, plus some rail stations, bus locations and ferry ports associated with intermodal travel. Check the location type and full name when selecting a result.

The letters often resemble a name, but that is not a reliable decoding rule for every identifier. Available combinations and assignment histories differ. Avoid guessing the airport from the first letters of a city name.

## What ICAO indicators are used for

ICAO is the International Civil Aviation Organization. Its Location Indicators manual, Doc 7910, lists four-letter indicators and corresponding IATA codes where available. Operational tasks differ from passenger shopping: these identifiers serve aviation information and flight operations.

For example, Switzerland's aviation authority lists Geneva Airport as IATA **GVA** and ICAO **LSGG**. The two codes refer to one airport. Having an identifier in one system does not establish that every location must also have one in the other.

| System              | Example and purpose             |
| ------------------- | ------------------------------- |
| IATA: three letters | GVA — commercial travel systems |
| ICAO: four letters  | LSGG — aviation operations      |

![Travellers examine a city overview showing several airports](https://roadme.io/blog/content/images/2026/10/roadme-image-69.webp)

## Why a city code does not identify your airport

When several airports serve a city, a metropolitan code may support a broader search. IATA's example is **WAS** for the Washington area, with separate airport codes **DCA, BWI and IAD**.

A metropolitan search can widen your options, but establish the actual airport for every segment before buying. Compare your arrival airport with the next departure airport and check the return journey separately. The same city name does not mean all movements happen in one building.

An airport code does not specify the terminal, gate or time. Check local hours and calendar dates separately using our guide to [time zones on flight tickets](https://roadme.io/blog/time-zones-dates-in-tickets/).

## What to match before setting off

Record the full airport name and code from your current ticket, terminal, flight number, local date and time. Compare these with carrier and airport information. A flight number or booking reference is a different field from an airport identifier.

IATA provides an official Airline and Airport Code Search. For ICAO, use reliable aeronautical information about the location; do not convert codes by adding or removing a letter yourself. If your ticket and ground-transfer booking name different airports, correct the transport arrangements before travelling.

Once the airport is confirmed, calculate the journey to accommodation and remaining time at the destination. A long additional transfer can substantially change arrival day.

> For city visits, try a day-by-day plan in [RoadMe](https://roadme.io/?ref=roadme.io) around your interests and pace, keeping suitable stops after the transfer.

Our guide to [getting through the airport on your first flight](https://roadme.io/blog/first-flight-how-to-get-through-the-airport-from-arrival-to-boarding/) explains check-in, controls and boarding. Codes help identify the place; procedures and deadlines still need to be checked for your flight.