What to check before you book a connection

Every airport publishes a minimum connection time, and booking systems will build any itinerary that clears it. That figure assumes both flights are on time, that you do not need to clear immigration, and that your gates are not at opposite ends of the airport.

Treat it as the point below which the connection is impossible, rather than the point above which it is fine.

Before accepting a connection, work through these. They take two minutes and they are the difference between a tight connection and an unmakeable one.

• Do you change terminal? Inter-terminal transfers at large hubs can consume half an hour on their own.
• Do you clear immigration and customs? Entering a country to connect means queueing, collecting bags, and re-checking them.
• Is it one ticket or two? On a single ticket the airline rebooks you when you misconnect. On two separate tickets, a missed connection is your problem and your cost.
• Is the connection the last departure of the day? If it is, a missed connection means an overnight rather than a two-hour delay.
• Are both flights operated by the same airline or alliance? Baggage transfer between unaffiliated carriers is frequently not through-checked.

On the return leg of a trip, a tight connection costs you an inconvenient evening. On the outbound leg of a trip with a fixed commitment at the other end — a wedding, a cruise departure, a conference — it can cost you the reason you travelled.

The asymmetry is worth pricing. If a longer connection is available for a modest difference on the outbound, take it, and save the tight one for the way home.

On a single ticket, the operating carrier is responsible for getting you to your destination, and depending on where you are flying, statutory compensation may apply on top. Keep boarding passes and any written notice of the delay reason — the claim usually turns on what the airline said caused it.