When you are earning miles, you certainly don’t know the value of it until you have to buy one.
When do you buy miles? When you need to redeem your points for a free ticket but you don’t have enough points. You are a frequent flyer now, so go ahead and log in, make your selection for a free ticket and put it on hold without a credit card (only members can do that, American Airlines will hold your reservation for 5 days with no obligation to buy). The website will calculate how many miles you need for the free ticket and how many miles you are missing so you won’t need a calculator. If you still haven’t purchased your ticket by midnight on the 5th day, the airline will cancel your reservation without penalty and release the seats for purchase.
When you don’t have enough miles for a free ticket you can purchase the missing miles from your airline, which are immediately deposited into your frequent flyer account after payment. Miles are sold in batches and the more miles you buy the less they cost. Also keep in mind that over a certain amount of miles you get free bonus miles so if let’s say you need 11,000 miles technically you only need to pay for 10,000 because you are getting 1,000 for free. Over 25,000 miles you are getting 10,000 bonus miles for free! When your purchased miles are deposited into your account, go ahead and “pay” for your reservation (which was now on hold) and your miles will be deducted from your frequent flyer account.
Here is an example of air mile costs:
1,000 miles cost $29.50
2,000 miles = $59
3,000 miles = $88.50
4,000 miles = $118
Over 5,000 miles you will receive 1,000 bonus miles for free and pay $147.50
10,000 miles + 1,000 miles for free = $295
Over 25,000 miles you will received 10,000 bonus miles for free and pay $737.50
40,000 miles +10,000 miles = you pay $1,180
So officinally, when you need 50,000 miles for a free European ticket from the continental USA; you had zero miles you would need to pay $1,180. Now you know, how important it is to earn miles and wait till you have enough for a free ticket. In my 25 years of traveling I only bought air miles once because I wanted us to fly together.