Every now and then, airlines do throw passengers a bone. They'll credit you if you cancel before takeoff, refund you if the fare goes down after purchase, make it up to you when you get bumped from a flight, soften the blow if they can't get you home due to a mechanical failure or say they’re sorry for truly execrable service (but it has to be really, really bad, and you usually have to ask for satisfaction). And they often do this in the form of a voucher, good for future travel, usually valid within a year of issue.

              However, there's credit, which is what most people expect these days – automatic, easily applied to your credit card account; and there's the voucher.  And in some cases, Airfarewatchdog.com has found, redeeming vouchers triggers unexpected fees and involve a good deal of inconvenience.

So much so that, until recently, you'd be justified in calling an airline voucher That Piece of Paper We Give You That's So Hard To Convert To A Ticket, We're Positive You Won't Even Try. That is, at least, what I called the last paper voucher I received, issued by Delta.

            I was jazzed to see complimentary travel in my future. However, I quickly learned that it was a lot easier for Delta to hand out vouchers than it was for me to cash mine in. I could find no way to use it online. Turned out that I would have to call the 800 number to redeem.   Then, after a long period on hold, and after selecting dates and times, I was informed that the reservation was only tentative. To seal the deal, I had to go to my nearest ticket office, which in your case may be your nearest airport. Whether or not I was being singled out for aggravation will forever go unconfirmed; Delta spokesperson Susan Elliott was understandably keen to focus on how things had changed. Today, Elliott says, paper vouchers are almost a thing of the past – now, travelers receive e-vouchers with reference numbers that, once typed in with your reservation on Delta.com, will be automatically applied to your bill. Still, this is very much an almost – paper vouchers are still around for credit on international travel and remain the currency for some awards-travel related scenarios.

In cases like these, travelers would need to call to redeem, in which case, they're slapped with the $25 phone fee that Delta now charges.  A charge for free travel? Yep, pretty much. After all, Delta and American now charge between $25 and $50 to obtain “free” frequent flyer tickets, even if done online.

SAY, WHAT'S A VOUCHER?

              You'd think it was as simple as a voucher being a gift, whereas credit is something issued for a purchase previously made. It's not. As mentioned above, if you get bumped, sometimes you get the voucher. If, for instance, the voucher was for international travel on Delta, now you're paying more to rebook. Vouchers, though, are issued for many reasons. Continental, for example, issues them when you find an itinerary booked on Continental.com for more than $10 less, after purchase. The airline, once they are satisfied you meet all requirements, will issue you a $100 chit, formally known as an Electronic Travel Certificate, redeemable for free, online.  US Airways has more than a half-dozen different types of vouchers, from a $25 Air Check on upward, mostly handed out in various scenarios involving passenger inconvenience. Luckily, while you need to call the 800 number to apply the voucher to future travel, you won't have to pay a fee (which is otherwise $25 for domestic and $35 for international travel). The airline does say, however, that you will have to make payment at "a valid location" (read: inconvenient) within 24 hours of booking over the phone.           

American Airlines has a sort of won't-know-until-you-get-there policy.  For example, says spokesperson Tim Wagner, in the event of customer service issues, you might either receive electronic or paper vouchers, depending on the type of issue that arises. If, for instance, bad weather cancels flights, those who are traveling on non-refundable tickets will receive paper vouchers, which means you'll need to call or show up in person to redeem. However, in cases like these, there's no booking fee. United also makes you call to redeem a paper voucher, and that also applies when redeeming an unused ticket from a cancelled trip.  We tried to get United to say whether or not either situation results in the $25 call center fee that the airline now charges, but spokesperson Robin Urbanski-Janikowski would only say that it depends on what type of voucher the traveler was trying to redeem. (Read that as a yes, until told no.)    Where United is keeping up with the times, though, is the issuance of electronic certificates in situations such as their Low Fare Guarantee program, where you can get $50 plus the difference in fare between what you booked on United.com and a lower price you found elsewhere, refunded to you electronically, and good for purchases online.

 IF ONLY IT WERE ALWAYS THIS EASY

             All the confusion over the various steps one has to take to redeem your credit appears to be entirely foreign to newer airlines such as JetBlue. Spokesperson Alison Eshelman says that because they are a "paperless" airline, there is no scenario where a credit issued will result in additional fees – unless, of course, you decide that you'd prefer to book with a human being vs. the airline's website. For that, there's a $15 fee. Northwest also issues electronic credit vouchers in cases of "service-related events," for instance, delays and bumps. You can redeem vouchers online not only for future travel, but also for additional charges and extra miles. Flexibility and ease of use – how novel is that.