Research which airlines fly to your required destination. Most airlines have partnerships with several other carriers. This allows points to be used across many airlines. For example, points on Continental Airlines can be used on European-based Lufthansa airlines. The two carriers are both members of the Star Alliance network.
Investigate flight times and dates. Go to the website of the chosen airline and note the best flight options for your destination. You can also call the airline directly and speak to a customer service representative. Do not, however, book the flight at this time.
Go to the Membership Rewards website. Log into your account. There will be an option to transfer your points. After you click on this, you will be guided to a list of airlines and travel options. For some airlines, Membership Rewards points transfer into the airlines' frequent flyer account immediately. For other airlines, it can take a few days for points to transfer. For Continental Airlines, for example, the transfer is immediate. Other airlines may take a day or two to transfer the points.
As a reference, as of 2010, 25,000 points will generally get you a round trip ticket within the United States. For tickets outside the United States, the amount of points required increases, and varies, depending on where you want to go. For example, going to Hawaii in coach class during high season will likely cost about 100,000 points. But, the same trip during the low season will likely cost only 50,000 or so. Tickets to Buenos Aires on Continental via Houston generally run about 50,000, a steal, considering the cost of that same ticket will run about $900.
Book the flight you want. After making sure the points have transferred into the airline frequent flyer account of choice, complete the reservation either online or via customer service.
