What is the difference between an IATA code and an ICAO code?

An IATA code is a 2-character code (like AA for American, DL for Delta, TK for Turkish) used on boarding passes, baggage tags, and flight booking engines. An ICAO code is a 3-letter identifier (like AAL, DAL, THY) used by air traffic controllers and pilots for flight plans and radio transmissions.

What does "Y" class mean on an airplane ticket?

In commercial aviation, "Y" denotes standard full-fare Economy Class. Other common single-letter codes include "J" or "C" for Business Class, "W" for Premium Economy, and "F" for First Class.

Why do budget airlines like Ryanair (FR) and easyJet (U2) have strict bag sizes?

Low-cost carriers generate ancillary revenue through baggage fees and optimize aircraft turnaround times (25-30 minutes). Enforcing small under-seat bags prevents cabin overhead bins from filling up, eliminating gate-check delays.

Aviation & Flight Decoder

Airline 2-Letter Codes Meaning

Wondering what airline flight AA 100, DL 405, or TK 1 is? Decode 2-letter IATA flight codes, callsigns, carry-on baggage policies, and global alliances.

Alliance:

Showing 16 airlines

ICAO: AALRadio Callsign: "AMERICAN"

United States 🇺🇸

American Airlines

World’s largest airline by fleet size and scheduled passengers.

Primary Hubs: Dallas/Fort Worth (DFW), Charlotte (CLT)

Alliance: Oneworld

Carry-On Baggage Rule:

1 free carry-on bag + 1 personal item included on all fares (even Basic Economy)

Flight prefix: AA###Active Carrier

ICAO: DALRadio Callsign: "DELTA"

United States 🇺🇸

Delta Air Lines

Oldest operating airline in the United States, headquartered in Atlanta.

Primary Hubs: Atlanta (ATL), Minneapolis (MSP), Detroit (DTW)

Alliance: SkyTeam

Carry-On Baggage Rule:

1 free carry-on bag + 1 personal item. No maximum weight limit on most domestic routes.

Flight prefix: DL###Active Carrier

ICAO: UALRadio Callsign: "UNITED"

United States 🇺🇸

United Airlines

Major US network carrier and founding member of Star Alliance.

Primary Hubs: Chicago O’Hare (ORD), Denver (DEN), Houston (IAH), Newark (EWR)

Alliance: Star Alliance

Carry-On Baggage Rule:

Standard fares get 1 free carry-on. Note: Basic Economy only allows 1 small personal item under the seat!

Flight prefix: UA###Active Carrier

ICAO: SWARadio Callsign: "SOUTHWEST"

United States 🇺🇸

Southwest Airlines

World’s largest low-cost carrier, famous for open seating and free checked baggage.

Primary Hubs: Dallas Love (DAL), Denver (DEN), Las Vegas (LAS)

Alliance: None / Low-Cost

Carry-On Baggage Rule:

1 free carry-on bag + 1 personal item + 2 free checked bags ("Bags Fly Free").

Flight prefix: WN###Active Carrier

ICAO: JBURadio Callsign: "JETBLUE"

United States 🇺🇸

JetBlue Airways

Known for free high-speed Fly-Fi internet and extra legroom coach seats.

Primary Hubs: New York (JFK), Boston (BOS), Fort Lauderdale (FLL)

Alliance: None / Low-Cost

Carry-On Baggage Rule:

All Blue Basic fares now include 1 free overhead carry-on bag plus personal item.

Flight prefix: B6###Active Carrier

ICAO: RYRRadio Callsign: "RYANAIR"

Ireland 🇮🇪

Ryanair

Europe’s largest budget airline by passenger count.

Primary Hubs: Dublin (DUB), London Stansted (STN)

Alliance: None / Low-Cost

Carry-On Baggage Rule:

Strict! Value fare includes only 1 small personal item (40x20x25cm). Overhead trolley requires "Priority" add-on.

Flight prefix: FR###Active Carrier

ICAO: EZYRadio Callsign: "EASY"

United Kingdom 🇬🇧

easyJet

Pioneer of low-cost European point-to-point flights.

Primary Hubs: London Gatwick (LGW), Milan Malpensa (MXP)

Alliance: None / Low-Cost

Carry-On Baggage Rule:

Standard ticket includes 1 under-seat bag (45x36x20cm). Large overhead bag requires seat selection or booking fee.

Flight prefix: U2###Active Carrier

ICAO: THYRadio Callsign: "TURKISH"

Turkey 🇹🇷

Turkish Airlines

Flies to more countries (129+) than any other airline in the world.

Primary Hubs: Istanbul Airport (IST)

Alliance: Star Alliance

Carry-On Baggage Rule:

Economy includes 1 free carry-on bag (8 kg / 17.6 lbs) + 1 personal item. Business includes 2 carry-ons.

Flight prefix: TK###Active Carrier

ICAO: BAWRadio Callsign: "SPEEDBIRD"

United Kingdom 🇬🇧

British Airways

Flag carrier of the UK, famous for its historic "Speedbird" callsign.

Primary Hubs: London Heathrow (LHR), London Gatwick (LGW)

Alliance: Oneworld

Carry-On Baggage Rule:

Generous 23 kg (51 lbs) weight allowance for both your cabin bag and your personal handbag/laptop case.

Flight prefix: BA###Active Carrier

ICAO: DLHRadio Callsign: "LUFTHANSA"

Germany 🇩🇪

Lufthansa

Europe’s largest airline group and co-founder of the Star Alliance.

Primary Hubs: Frankfurt (FRA), Munich (MUC)

Alliance: Star Alliance

Carry-On Baggage Rule:

1 free carry-on (8 kg / 17.6 lbs, 55x40x23cm) + 1 personal item. Strictly weighed at gate.

Flight prefix: LH###Active Carrier

ICAO: AFRRadio Callsign: "AIRFRANS"

France 🇫🇷

Air France

French national carrier, member of Air France-KLM group.

Primary Hubs: Paris Charles de Gaulle (CDG), Paris Orly (ORY)

Alliance: SkyTeam

Carry-On Baggage Rule:

1 cabin bag + 1 personal item with a combined maximum weight of 12 kg (26.4 lbs) in Economy.

Flight prefix: AF###Active Carrier

ICAO: KLMRadio Callsign: "KLM"

Netherlands 🇳🇱

KLM Royal Dutch Airlines

Oldest operating airline in the world still flying under its original name (founded 1919).

Primary Hubs: Amsterdam Schiphol (AMS)

Alliance: SkyTeam

Carry-On Baggage Rule:

1 carry-on bag (55x35x25cm) + 1 accessory up to a total weight of 12 kg in Economy.

Flight prefix: KL###Active Carrier

ICAO: UAERadio Callsign: "EMIRATES"

United Arab Emirates 🇦🇪

Emirates

Global long-haul giant operating the world’s largest fleets of Airbus A380 and Boeing 777 aircraft.

Primary Hubs: Dubai International (DXB)

Alliance: None / Low-Cost

Carry-On Baggage Rule:

Economy allows 1 carry-on bag (7 kg / 15 lbs). Strictly enforced dimensions.

Flight prefix: EK###Active Carrier

ICAO: QTRRadio Callsign: "QATARI"

Qatar 🇶🇦

Qatar Airways

Frequently voted World’s Best Airline by Skytrax, famous for Qsuite business class.

Primary Hubs: Doha Hamad International (DOH)

Alliance: Oneworld

Carry-On Baggage Rule:

Economy includes 1 piece up to 7 kg (15 lbs). Business/First class allows 2 pieces up to 15 kg total.

Flight prefix: QR###Active Carrier

ICAO: SIARadio Callsign: "SINGAPORE"

Singapore 🇸🇬

Singapore Airlines

Legendary 5-star Asian flag carrier renowned for unmatched hospitality and in-flight dining.

Primary Hubs: Singapore Changi (SIN)

Alliance: Star Alliance

Carry-On Baggage Rule:

Economy: 1 carry-on piece up to 7 kg + 1 personal item. Premium Economy: 1 piece (7 kg). Suites/First: 2 pieces.

Flight prefix: SQ###Active Carrier

ICAO: WZZRadio Callsign: "WIZZ AIR"

Hungary 🇭🇺

Wizz Air

Ultra low-cost European carrier with pink and purple aircraft liveries.

Primary Hubs: Budapest (BUD), London Luton (LTN), Rome Fiumicino (FCO)

Alliance: None / Low-Cost

Carry-On Baggage Rule:

Free ticket includes 1 small bag (40x30x20cm). Overhead trolley requires "WIZZ Priority".

Flight prefix: W6###Active Carrier

Boarding Pass Ticket Fare Letters (Y, J, F, W)

What that single letter printed on your physical boarding pass means.

Class: Y, B, M, H

Full Fare / Flexible Economy Class

Top-tier economy seats eligible for mileage upgrades and refunds.

Class: Q, V, W, S, T, L, K

Discount / Restricted Economy Class

Standard non-refundable tickets with change fees.

Class: W, P, A

Premium Economy Class

Wider seats, dedicated legroom cabin, and enhanced meals.

Class: J, C, D, I, Z

Business Class (Executive)

Lie-flat seats, lounge access, priority boarding, and premium dining.

Class: F, A, P

First Class

Ultimate luxury suites, personal concierge, and champagne service.

Got "SSSS" printed on your boarding pass?

Check out our complete Airport Boarding Pass Symbols Guide for SSSS, TSA PreCheck, Group Numbers, and SBY codes.

Decode Boarding Passes →