Airport layovers: what changes when flights are on separate tickets

First find out whether it is one booking or two

A connection can look identical on a search screen while involving a very different journey. Heathrow defines a connecting flight as multiple flights booked on one ticket. With separate tickets, you may need to pass immigration, collect checked baggage, check in again, drop bags and clear security. Verify the ticketing arrangement directly with the airline or seller; one itinerary email does not by itself prove bags are checked through or that the next carrier will wait.

Ask before booking: will baggage be tagged to the final destination, do you receive both boarding passes, and what happens if the first flight is delayed? Get the response in writing. Check whether the onward flight departs from the same airport—especially in cities with multiple airports—and whether a terminal change is required.

Allow for the steps between aircraft

A connection may require more than walking to another gate. At Heathrow, all connecting passengers pass security again and some journeys involve a terminal transfer; most passengers on a connected booking do not collect bags, but travellers on separate tickets may need to. Local airport instructions are the useful source for route-specific steps. Find the airport’s connection page and check the required terminal, transfer route, immigration process, security screening and check-in deadline.

Separate-ticket self-transfers add uncertainty: the first flight could arrive late, baggage delivery may take time, and check-in for the second flight may close before departure. Do not treat the advertised time between scheduled arrivals and departures as all usable time. Include taxiing, disembarkation, queues, baggage collection, terminal transfer and the next airline’s bag-drop deadline.

Use the airport’s advice, not a universal minimum

There is no single layover duration that is safe for every airport, itinerary or ticket type. Gatwick publishes different advice for same-terminal and terminal-change connections where passengers already hold a boarding pass, and says airline minimum connection requirements may differ. For a self-transfer involving checked baggage or immigration, Gatwick advises checking the airline. These are airport-specific examples, not universal guarantees.

A longer buffer reduces some timing pressure but does not eliminate disruption risk. For separate tickets, consider whether you can tolerate buying a replacement onward ticket, an extra night or a new transfer if the first leg is disrupted. Travel insurance wording may or may not cover missed connections; check the precise terms. An overnight gap or a flexible onward ticket may be more suitable than a tight self-transfer, depending on your needs.

Make a connection plan before paying

Write down the airports, terminals, ticket structure, baggage arrangements, immigration requirements, check-in closing time and airline minimum. Confirm whether you need permission to enter the transit country if you must go landside to collect bags. Consult official government entry advice and the airport’s own connection instructions. If anything remains unclear, contact the carrier before purchase.

For a single-ticket itinerary, still review the connection time and assistance process if a delay causes a missed flight. For separate tickets, save both airlines’ contact details and keep essential medication and valuables in cabin baggage. Avoid building a plan around best-case assumptions: choose the connection that remains workable with a queue, a terminal move or a modest delay.

Plan for what happens if you are delayed after landing. Know where you would find the airline desk, whether you can reach the next airline without exiting the secure area, and how you would contact the person meeting you. If the second flight is on another booking, check its change and no-show rules before travel. A deliberately generous connection can still be lost in a major disruption, so the financial downside should be part of the decision.