Just like that milk in your fridge, miles will last a while, but not forever. Until the late ’90s, miles did not expire, but they kept building up faster than they were redeemed and this presented a problem for the airlines. You see, in accounting rules, each mile represented a potential expenditure the airline would make in the future (the cost of the free ticket) so on thier books were held as liabilities. These liabilities reached the point where they amounted to billions of dollars and which the airlines needed to hold assets against in case they were all redeemed. The airlines came up with the idea that many of these miles had been earned by people years ago and forgotten about. Therefore, they established expiration dates. No activity, meaning earning or redeeming, and the miles would disappear from your account. I have seen some people lose over 100,000 miles because they forgot about the expiration date.
Ironically, Delta – one of the first airlines to establish expiration dates – is the only one which now has no expiration date on their miles. All the other airline programs require some activity within a 18 – 36 month period or they go poof. This is especially important to monitor if you followed my previous advice and did not allow any mile to go unclaimed. So keep an eye on the 5,000 miles in a stray account to ensure they don’t expire and perhaps you will have an opportunity to use them some day. Or, just as likely, your favorite airline will buy up that airline and combine those miles. I have never collected a lot of miles in American or USAIR, but in a few months they will combine and I will have enough for a free ticket.
Fortunately, there are easy ways to keep your account active. Remember that ANY activity keeps your account active and resets the clock. Here are some simple ways to do that:
1. Get the credit card from that program. One charge a month is more than enough to keep your account active. If you are following this tactic, I recommend using a no fee card.
2. My favorite technique is to use the miles I get from car rentals. these 50-200 miles would not mean very much when totaled with the 1,000,000+ miles that I have with UA, but when I credit them every six months to AA or US, they keep those accounts active and even add a significant percentage to the total needed for a free ticket.
3. If you use Super Shuttle to go to the airport, you can credit the few hundred miles you get to certain airlines.
4. Redeeming miles also counts as activity and starts the clock all over again. A magazine subscription for 1,000 miles is easily done on most airline programs.
5. Most programs will give you a few miles for buying flowers.
6. Donate miles to USO or another military charity such as the Fisher House’s Hero Miles Program. You can get miles for donating dollars or donate miles to the charity which will then count as activity.
7. You can exchange miles between programs using www.points.com. This is usually a bad exchange rate, but can be a great use of miles you gathered on a program that you are sure you will never use. Keep it to the minimum allowed just to keep your miles alive.
8. Finally, and I only recommend this as a last resort, you can buy miles from most programs. The reason I recommend this only as a last resort is that the cost per mile is pretty high. Keep it to the minimum allowed and buy the minimum to keep your miles from expiring.
For a great reference and even more little ways to keep your miles alive, I recommend reading Daraius’ Million Mile Secrets blog. This post about keeping your airline miles from expiring without flying is the most authoritative that I know of. It comes with a great chart and all sorts of possibilities to keep an account alive.