Several sources publish data on the correlation between advance purchase period and airfares. The ideal time to buy a domestic ticket is 54 days in advance, says or seven weeks ahead. For international trips, the ideal period is 171 days ahead of departure. Some studies refine the estimates: 96 days before trips to Europe and 96 days prior to Latin America trips. Most sources indicate that you can come close to the absolute lowest price over a wide range of dates: about 30–100 days in advance.
Here’s the challenge: book too early and you’re missing out on the price slashing that happens as airlines attempt to fill empty seats on unsold flights. On average, sometime around 225 days out (seven and a half months), fares start to drop and by 100 days out (three and a half months) they fall to within $10 of their low point. From there they continue to drop, slowly but steadily, until reaching a low 54 days before departure. After 54 days, fares start to climb again, remaining within $10 of that low until 30 days out. Then, the increase begins to accelerate and shoot up dramatically within 14 days prior to departure. Booking too late is especially bad; you pay a huge premium for buying within a week or two of departure—even on airlines that nominally assess no advance-purchase limit.
The claim that there is one time of the day or one day of the week that is better than another is generally regarded as false because fares are dynamic, since they are based on market conditions and the actual number of passengers who are currently booked on a specific flight. But in practice, many airlines announce sales on a Monday, with the other airlines matching certain fares the following day. The best way to keep on top of airfare sales is to subscribe to one or more airfare alerts such as BookingBuddy.com or Airfarewatchdog.com. You can also get fare alerts directly from your favorite carrier. Many airlines offer weekly or periodic email notifications of special sales and other useful information and it’s a good idea to set up alerts from an airline with which you frequently fly, especially if you collect miles.
What about getting the best seats?
To find out which seats are the best on a particular aircraft, go to SeatGuru.com or SeatExpert.com. Both highlight the best seats on every plane and list exactly how much legroom and pitch each one has. They also tell you if there are power ports or personal TVs with each seat. Keep in mind that airlines can change aircraft types at the last minute, so there are no guarantees. Most airlines will allow you to upgrade your coach seat. Just make sure you're getting something worthwhile, like more legroom, for your money. Some airlines (ahem, American) will charge you extra just for putting you toward the front of the cabin, with no extra perks included. Don't be fooled.
How Long Should Connection Times Be Between Flights?
Trying to make a tight connection between flights is a surefire way to add unnecessary stress (and a possible missed flight) to your journey. And you can't always count on airlines for guidance; their recommended connection-time minimums often leave frequent travelers wondering how anyone could possibly get to another flight in the suggested amount of time. The amount of time you should allow between connecting flights varies depending on the airport, the airline, and whether or not you'll have to clear customs or go through security to switch terminals. As a general rule of thumb, it's safe to assume that, on domestic connections, anything less than 45 minutes is a bad idea—and you'll likely be better off doubling that amount of time and scheduling about 90 minutes between flights. For international flights connecting with domestic flights, add enough time to clear customs.
How Far in Advance Should You Check In for a Flight?
If you're checking in online, most airlines let you do so starting 24 hours in advance until one or two hours prior to departure. Benefits of checking in online include better seat selection (or higher seating-choice priority and not having to stand in line to check in at the airport.
Airlines have specific guidelines about how far in advance you should check in at the airport, depending on your destination. Many airlines require that you check in at least 30 to 45 minutes before your flight, but that's cutting it dangerously close at most airports where you'll still have to navigate large terminals and long security lines.
How Far In Advance Should You Get To The Airport?
As a general rule, it's great to get to the airport two hours in advance of domestic flights and three hours before international flights. However, if you're looking to shave off a bit of your hurry-up-and-wait time at the gate, you can hone the equation for your specific situation.
If you've checked in and printed your boarding pass before arriving, you've just saved yourself 20 minutes and can adjust your airport arrival time accordingly. Likewise, you've saved yourself a bit of time if you're only traveling with a carry-on and don't have to check bags. However, unless you're cleared for expedited screening (through TSA PreCheck at one of the participating airports), you'll need to budget plenty of time to get through airport security. Assume that security lines will be particularly slow during the peak airport-traffic hours of 6:30 to 9:30 in the morning, 11 AM to 2 PM, and 3:30 to 7:30 PM.
How Far in Advance Should I Be at the Departure Gate?
Ever heard of a boarding-gate deadline? Most airlines have them, and they're important: If you don't make it to the gate within the allowed window, airlines don't have to let you on the flight. Boarding deadlines vary wildly based not only on the airline but also on the destination. For instance, on some Delta Shuttle flights, passengers need to be at the gate only five minutes prior to departure, but on Delta's international flights to Dublin and Istanbul, passengers must be at the gate an hour in advance. On many U.S. and Canadian airlines, passengers are expected to arrive at the gate about 15 minutes before departure for domestic flights and 30 minutes prior for international flights. However, since times do vary, check boarding-gate deadlines in advance so you don't cut it too close. Airlines usually have a list of boarding-gate deadlines by airport and arrival city on their websites.
BONUS 411: When Can You Check In and Check Out Of A Hotel?
As with cancellation policies, hotels' check-in and checkout times vary by location. However, there are some similarities among lodgings, with check-in times starting mid-afternoon, usually around 3 PM, and checkout times falling in the late morning, usually at 11 AM or noon. At many hotels, check-in and checkout times are far from set in stone. Loyalty members often get the option of early check-in or late checkout, and sometimes hotels offer the option with certain packages or room types. And if you've got a late flight or just need a home base for a few hours, it never hurts to call the front desk and ask. Often, the hotel will be happy to oblige. If you arrive early and your room isn't ready, most hotels will store your luggage until you can check in (sometimes for an extra fee). And if you plan on arriving long after the check-in time, it's worth a quick phone call to alert the front desk of your estimated arrival time so they don't think you're a no-show and give away your room.