Open jaw
An open-jaw itinerary arrives in one city and returns from another. A traveller might fly from Newark to Lisbon, travel by rail to Porto and fly home from Porto.
This avoids returning to the arrival city solely to catch the flight home. The airline still has to price the flights under compatible fare rules.
Multi-city
A multi-city itinerary contains more than two flown segments. It might include New York to Tokyo, Tokyo to Seoul and Seoul to New York.
The order matters. Moving one city can change available flights, connection time and the way fares combine.
What to compare
- Total travel time, not only flight time.
- Whether baggage is checked through on each connection.
- Airport and terminal changes.
- Separate-ticket risk.
- Change and cancellation conditions.
- Ground travel already planned between cities.
When separate tickets may be appropriate
Separate tickets can sometimes provide a useful route. They can also leave the traveller responsible when a delay on one ticket causes a missed flight on the next. That risk should be identified before purchase.