A day or two can really make a difference in air fares. If possible, try to have a few alternative dates of travel available. Airlines sell several classes of fares, not just first business and economy. A low fare might be sold out on one day but available the next. Checking the individual airline website is a good way to find the lowest fares. Most major airlines now allow passengers to book and pay online. Most will also show the individual fares for each day.
The more advance notice the airline has the better. Booking your ticket early increases the chances that the lowest airfares will be available. According to Michael Bluejay's How to Air Fare Guide, the fare difference from five days' advance notice to 26 days' advance notice can potentially vary by more than $200.
The airport that you travel from and arrive to can actually influence the ticket cost. For example, if you're traveling to London it is worth checking fares into Manchester, Liverpool and Birmingham. It is possible fares might be lower at alternate destinations. Just make sure to factor in the costs of any land travel needed to catch the flight. These need to be considered in the total cost of the ticket.
Airline auctions can be tricky but can amount to a large amount of savings. The customer searches out flights and places a bid. It is entirely up to the site if they will accept the bid or not. Auctions sites are no guarantee but some successful bids have amounted in savings of several hundred dollars.
For international travel, try taking advantage of the discount carriers. There are several that operate on the European mainland as well as Britain. The services are basic and travelers might have to pay to pack baggage. However, it isn't uncommon to see flights listed for less than 20 Euros, depending on the time of year you travel.
