Price is closer to a set of rules than to luck. What actually moves the number.
There is a lot of advice about buying on a particular weekday, but what really moves prices is demand on that route. During school holidays, long weekends and local festivals, fares are high whenever you buy. Off-season weekday departures are visibly cheaper. Asking whether you can shift when you travel beats agonising over when to buy.
Most search sites can show a whole month of prices at once. Moving your departure by a day or two often changes the fare substantially. If the destination is open, you can also enter only your origin and see where is cheap.
The lowest fare usually cannot be changed or refunded, excludes checked baggage, and charges for seat selection. Once you add a bag, the ranking often flips. Compare the total for the conditions you will actually use, not the headline fare.
Connections save money but cost time and energy. If the legs are booked as separate tickets, the second airline owes you nothing when the first one is late. Low-cost carriers start cheap but charge for everything else, so add what you need before comparing.
Confirm the name matches your passport exactly, whether arrival rolls over to the next day, and how far the airport is from the city. Name corrections usually cost money, and sometimes are not possible at all.
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