When booking your flights online, the old golden rule still applies: the earlier you book the better your chances of secureing a discounted rate!
Aim for at least twenty-one days before the departure date to avoid higher fares and the often exorbitant rates of buying just days in advance. There is, of course, a limit to the amount of time ahead you can book your tickets due to the fact that often ticket sales are announced just a couple of months before the departure date.
However, if you haven't managed to get in early, or there is an unexpected, last-minute situation that demands a flight, you might encounter sell-off fares which are highly discounted in order to fill the plane.
If you begin the online flight booking process, you'll soon discover a big discrepancy on flight fares just days apart. As with most transport, there are 'rush-hour' style busy trends, determined primarily by regular business travelers. Avoid typical business traveler times to get better discounts.
Don't forget to compare between websites as many online travel providers have special unique relationships with the airlines and are able to offer great discounts for specific periods.