One way vacations work, is that the airlines try to get full planes every day and not spread out bookings throughout the year. There might be something that allows a traveler who missed the "peak" to still get his/her reservation in. But for airlines that do it this way, a person who misses a specific time might miss out. Even with "special" accommodations that you know can work, it will still depend on how the airline approaches this and it is important to research them. A: While not all airlines will offer it, the majority of long haul US carriers offer flexible travel dates. The way this works is that when you book your trip and select your specific dates of travel, your payment will be non-refundable, and you will be locked into those dates. However, you can apply for a change of reservation that allows you to reschedule the dates you paid for, subject to a change fee. Here's the U.S. government's Travel Information Site describing your options if you're a member of the United States Military, and how to arrange for military leave: http://travinfo.us.fmprc.gov/mp2/mp2_text.cfm?currentMP=8 What I did was submit my request for special accommodations to the military member I was responsible for, and they reviewed and processed the request. Then I had the option of confirming the dates I requested (which were non-refundable) to make sure they were available, or requesting a change of reservation with a change fee. Both worked in my situation, although for a minor change (a different time of day), I didn't have to pay any fee. There was never a problem with changing dates once the ticket was purchased, and in my case, the change was approved. However, if your first airline of choice doesn't offer that service, your next best option is to check with another airline. A: This is possible with United and sometimes American. http://www.united.com/mileageplus/flexibleRouting.aspx#specialReq United also gives you a set number of changes per year. A: It's not possible if it's a regular flight from A->B, because in that case the tickets are sold in blocks. If the price to change the date is very high (it can be for the tickets), it's going to be harder to sell those tickets later when other customers want to buy them. If you want to travel from A->B->C with a layover of a day or two in B->D, then you can do it. You can even check-in in B, because there's no need to check-in in A at all. However if you check-in in A, your bag will be checked through B->D instead of the usual B->A. If this is really necessary, you should consider booking a separate (cheaper) ticket for your layover. A: I don't know how to find the answer for "usual" travel (i.e. one going from A to B). I'm not even sure if there are regulations about how a carrier can sell a single ticket without specifying a definite departure and arrival point. But in some cases there are airlines which do offer such options, for example Emirates and Qatar Airways. I have used both in these cases for going to Europe, and even for a longer trip. But to confirm, it may not work for every route and airline, and it may have conditions (such as the booking being made at least 3 days before travel). Update: Emirates for example has some info on their website about booking trips for layovers: Q: How do I book a flight that includes a layover? Ans: At the time of booking, Emirates’ call center staff can advise you on the best option, whether a single booking with a break, or two separate flights. Booking both legs of the trip individually might not make the most economic use of your time. But here, the "break" is not "rebooking" but a different airline. You may also wish to consider asking for special conditions to your ticket, like getting an airport lounge access. On the other hand, there are other airlines which don't support it at all: for example, Lufthansa does not offer it, and says it's not possible in their rules: I’ve just received an email from a reader who wants to know if it’s possible to purchase a single ticket from Germany to the USA and back that has no exact departure and arrival date. This isn’t possible. The rules state that the tickets have to be purchased for a specific date. This is also the case for flights from other destinations within Europe. I found this, and another similar one from a few years ago, both indicating that this is not possible. Update: Thanks to the comment from @Hendrik Brummerman above, I've updated the link to show it's not a "rule", but a specific booking service which supports it. Or you can not use a specific booking system. This is often offered on the airline site itself, or with a search site, like an Amex Travel, with which you can enter an origin and destination, then select "book with layover". And then the airline will list the flights with the necessary conditions to travel. (Also, as I suggested in my comment above, checking the rules and regulations is probably a good idea in order to see if you are able to make an informed decision, or if this is feasible at all.) When I was searching for this topic, I only found the possibility of traveling with a different company: Some companies will let you fly into one city and out of another, but usually for a fee. (So if you really want to save a trip or two, you should consider asking if your "flight options" are valid for such a ticket.) In my case, I found a travel agency which was willing to sell me a single ticket with a layover (although it was a "buy two, get one free" offer).