Travel & aviation glossary

The Association of British Travel Agents — a UK trade body whose members follow a code of conduct and offer financial protection for package holidays that do not include a flight (flight-inclusive packages are protected by ATOL instead). Look for the ABTA logo and membership number on a booking confirmation.

A commercial partnership between airlines that lets passengers earn and redeem loyalty points, use shared lounges, and book connecting itineraries across member carriers. The three global alliances are Star Alliance, Oneworld, and SkyTeam.

Income airlines earn from anything beyond the base fare — seat selection, checked baggage, priority boarding, onboard food, and commission on hotel or car-hire add-ons. Budget carriers rely heavily on ancillary revenue, which is why their headline fares look cheap.

Air Travel Organiser's Licence — the UK's financial protection scheme for package holidays that include a flight, run by the Civil Aviation Authority. If an ATOL-protected operator collapses, the scheme covers refunds or repatriation. Always check for an ATOL certificate when booking a flight-inclusive package.

The weight, size, or number of bags an airline permits per passenger for free, split into hand baggage (cabin) and checked baggage (hold). Allowances vary hugely by airline and fare type — budget carriers often charge for any baggage beyond a small personal item.

A premium cabin positioned between premium economy and first class, typically offering lie-flat or angled seating on long-haul aircraft, priority services, lounge access, and enhanced dining. Not all airlines offer a distinct first class, making business class the top cabin on many routes.

The category of seating and service on a flight — commonly economy, premium economy, business, and first. Cabin class determines baggage allowance, seat comfort, lounge access, and (under UK261) the reimbursement owed if you are downgraded.

The Centre for Effective Dispute Resolution — one of two CAA-approved Alternative Dispute Resolution bodies for UK aviation complaints (the other is Aviation ADR). If an airline rejects or ignores a compensation claim, its CEDR or Aviation ADR membership lets you escalate for free with a binding decision.

An arrangement where two or more airlines sell seats on the same physical flight under their own flight numbers. The airline that actually operates the aircraft — not the one you booked with — is the one legally responsible for delay or cancellation compensation.

A flight that requires changing aircraft at an intermediate airport to reach your final destination, as opposed to a direct or nonstop flight. Whether a missed connection is compensable under UK261 depends on whether both legs were booked on a single reservation.

An insurance term for cutting a trip short and returning home early, usually due to illness, bereavement, or another insured emergency. Travel insurance policies with curtailment cover reimburse the unused, non-refundable portion of the trip.

Being refused a seat on a flight you have a valid, confirmed booking for — most commonly because the airline oversold the flight. Also called "bumping". Involuntary denied boarding (you did not agree to give up your seat) triggers the same fixed UK261 compensation as a long delay.

A flight with a single flight number from origin to destination that may still stop en route to refuel or pick up passengers, without requiring you to change aircraft. This differs from a "nonstop" flight, which has no stops at all — the two terms are often confused.

An airline's obligation under UK261 to look after delayed or cancelled passengers regardless of fault — meals and refreshments proportionate to the wait, two free calls or emails, and hotel accommodation plus transfers if an overnight delay is unavoidable. This is separate from, and owed even when, fixed cash compensation is not.

The standard, lowest-cost cabin on most flights, offering the smallest seat pitch and most basic service level. Fare rules within economy (e.g. "basic economy" or "light" fares) can still vary baggage allowance and change flexibility significantly.

A digital pre-travel permission the UK requires from most non-visa nationals (including EU citizens) before travelling to the UK, distinct from a visa. It must be applied for online in advance and linked to your passport.

The European Travel Information and Authorisation System — a planned pre-travel screening requirement for visa-exempt visitors, including UK passport holders, entering most Schengen Area countries. Check the official EU ETIAS site for the current rollout status before travelling.

Events genuinely outside an airline's control — severe weather, air traffic control restrictions, security threats, political instability — that exempt it from paying UK261 compensation, though duty of care still applies. Crew sickness, staff shortages, and technical faults are generally NOT extraordinary circumstances under UK case law.

A short alphanumeric code on your ticket that identifies the exact fare rules applied — refundability, change fees, baggage allowance, and mileage-earning rate. Two passengers in the same cabin can have very different rules depending on their fare basis code.

The most premium cabin, offered by a shrinking number of airlines, typically featuring private suites, dedicated cabin crew, and the highest service level. Many airlines have discontinued first class in favour of a top-tier business class.

An additional charge some airlines add to the base fare to offset fuel costs, most commonly seen on loyalty-programme redemption bookings. Fuel surcharges are set by the airline, not regulated, and can vary enormously by route and carrier.

The Global Health Insurance Card — a free UK card that entitles holders to state-provided, medically necessary healthcare in the EU at the same cost as a local resident. It is not a substitute for travel insurance, which also covers repatriation, private treatment, and non-medical losses.

Services provided at the airport to turn a flight around — baggage loading, aircraft cleaning, catering, and passenger check-in — usually contracted out by the airline to a specialist ground handling company rather than performed by airline staff directly.

Baggage carried into the cabin rather than checked into the hold, subject to size and weight limits set by the airline. Also called cabin baggage. Many budget fares only include a small "personal item" for free, charging extra for a full-size cabin bag.

An airport where an airline concentrates connecting traffic, routing passengers from many origins through it to reach many destinations via a single stop. Heathrow (British Airways), Amsterdam Schiphol (KLM), and Dubai (Emirates) are examples of major hub airports.

A three-letter code assigned by the International Air Transport Association to identify an airport (e.g. LHR for London Heathrow) or a two-letter code to identify an airline (e.g. BA for British Airways). IATA codes are what you see on boarding passes and departure boards.

A four-letter code assigned by the International Civil Aviation Organization to identify an airport (e.g. EGLL for London Heathrow) or a three-letter code for an airline, used mainly in air traffic control and technical operations rather than passenger-facing material.

An agreement between airlines to handle each other's passengers and baggage across a connecting itinerary — checking bags through to the final destination and issuing a single boarding sequence — even when the airlines are not in the same alliance.

The full schedule of flights, connections, and dates that make up a trip, as distinct from a single ticket. One itinerary can be issued as multiple separate tickets, which matters for compensation rights if one leg is disrupted.

Both describe a stop at a connecting airport, but a layover is short (typically under 24 hours), while a stopover is a deliberate longer break — often used to visit the connecting city — usually 24 hours or more. Some airlines let you book a free or discounted stopover on their home hub as a marketing feature.

The percentage of an aircraft's available seats that are actually sold and occupied on a given flight, used industry-wide as a measure of how full flights are running. Airlines target high load factors to maximise revenue per flight.

A flight covering a long distance, typically over roughly 3,500 km or more than about six hours of flying time — the exact threshold varies by airline. UK261 compensation for long-haul delays and cancellations tops out at £520 per passenger.

An airline or alliance scheme (also called a frequent flyer programme) that rewards spending with points or miles redeemable for flights, upgrades, or other perks, and confers status tiers with benefits like lounge access and priority boarding.

Failing to make a connecting flight, usually because the first leg was delayed. Whether this is compensable depends on whether both flights were on a single booking reference — if so, the delay is measured at your final destination; if booked separately, each flight is assessed in isolation.

An international treaty setting airline liability rules for lost, damaged, or delayed baggage and other passenger claims on international flights, applied in UK law via the Carriage by Air Act 1961. Liability for baggage is capped at roughly 1,288 Special Drawing Rights (around £1,000–£1,150) per passenger.

Failing to check in or board a flight you booked without cancelling in advance. A no-show on one segment of a multi-flight ticket can cause the airline to automatically cancel the remaining segments, even if you intended to use them.

A round-trip ticket where the return flight departs from a different city than the outbound flight arrived at, letting travellers cover ground between the two (e.g. fly into Rome, travel overland, fly home from Milan) without buying two one-way tickets.

An airline's practice of selling more tickets than there are seats on a flight, anticipating that some passengers will not show up. When more passengers arrive than there are seats, the airline must ask for volunteers before denying boarding involuntarily.

A trip combining at least two elements — typically a flight and accommodation, or accommodation and car hire — sold or arranged together by one organiser. Package holidays carry statutory protection under the Package Travel Regulations 2018, including refund rights if the organiser cancels or significantly changes the trip.

A reference number issued by an airline's baggage desk when you report lost, damaged, or delayed checked baggage before leaving the airport. A PIR is essential evidence for a Montreal Convention baggage claim — always get one rather than reporting the issue later.

Passenger Name Record — the unique alphanumeric code (usually 5–6 characters) that identifies your reservation with an airline. Whether connecting flights share one PNR or are booked as separate PNRs determines your rights if a connection is missed.

A cabin positioned between economy and business class, offering extra legroom, wider seats, and enhanced service at a lower price than business class. Not all airlines offer premium economy, and its exact specification varies significantly between carriers.

Being placed on an alternative flight (or combination of flights) to reach your final destination after a cancellation or denied boarding, as an alternative to a refund. Under UK261, airlines must offer the choice between a refund and re-routing, not just one or the other.

A group of mostly-EU countries that have abolished passport checks at their mutual borders, functioning as a single travel zone. UK passport holders can visit for up to 90 days in any 180-day period without a visa, but are still subject to entry/exit stamping and, once introduced, ETIAS pre-authorisation.

Section 75 of the Consumer Credit Act 1974 — a UK law that makes your credit card provider jointly liable with the retailer for purchases of £100–£30,000 paid for (even partly) by credit card. It is a common fallback route for recovering money if an airline or travel operator goes out of business.

A flight covering a relatively short distance, typically up to around 1,500 km within Europe. UK261 compensation for short-haul delays and cancellations is capped at £220 per passenger, the lowest of the three distance tiers.

A delay where passengers are held on the aircraft, either before departure or after landing, without access to the terminal — for example, waiting for a gate to become free. Extended tarmac delays can still count toward UK261 arrival-delay compensation once the aircraft door actually opens at the destination.

A visa required by some countries to pass through their airport en route to a different destination, even without leaving the airport or the country. Requirements vary by nationality and airport — always check transit visa rules for every stop on a connecting itinerary, not just the final destination.

Shorthand for The Air Passenger Rights and Air Travel Organisers' Licensing (Amendment) (EU Exit) Regulations 2019 — the UK's post-Brexit version of EU261, giving passengers fixed cash compensation (£220–£520) for flight delays and cancellations within the airline's control.

Being moved to a higher cabin class than booked, either through paid upsell, loyalty status, or an operational decision by the airline. The opposite of a downgrade, which — unlike an upgrade — entitles you to a statutory partial fare reimbursement under UK261.

An arrangement allowing citizens of certain countries to enter another country without a traditional visa, often still requiring an electronic pre-travel authorisation (such as ESTA for the US or the UK's ETA). "Visa-free" and "visa waiver" are often used loosely, but many visa waiver schemes still require online registration in advance.

An arrangement where one airline supplies an aircraft, crew, maintenance, and insurance to operate flights on behalf of another airline, which sells the tickets under its own brand. Passengers may not realise which airline is actually operating a wet-leased flight, though the operating carrier is still the one legally liable under UK261.