Airline Secrets: What Is Fuel Dumping?

To wrap up this series on nifty little tricks within the airline ticketing ecosystem, I wanted to spend some time talking about fuel dumping, an ingenious and extremely black-hat method of purchasing airline tickets at a fraction of the cost. 

Now, before you get too excited, I should begin with the disclaimer that while the concept of fuel dumping can be grasped quite easily, it’s very difficult to actually put into practice.

It’s similar to manufactured spending – you can easily figure out the general principles of how it works, but the key methods and information on how to make it happen tends to be a closely guarded secret – except I’d say that figuring out MS is child’s play in comparison!

The goal of this article is to shed light on something interesting that you might not have known about, and to get you thinking about the intricacies of airline ticketing in a novel way. I’m not going to spill any juicy 3Xs (read on for what that means), mainly because I haven’t really been keeping up with the fuel dumping game in recent times. You should therefore treat this article as merely a starting point on this topic rather than an in-depth guide of any sort.

In This Post


Fittingly, the term “fuel dumping” originally came from the aviation world, referring to an emergency procedure used by various aircraft during a flight. If an emergency situation were to demand that the aircraft reduce its weight, the plane can “dump” any excess fuel into the air via a set of nozzles located on the wing.

The term was co-opted by savvy fliers when this creative airline booking ploy was discovered.

If you’ve ever tried to redeem miles for a flight, you’ll likely be familiar with the “fuel surcharge” – the pesky surcharge that’s supposed to reflect the cost of fuel, but in reality functions as little more than a pure cash grab by the airlines. Now, when you book flights using cash, there’s usually a fuel surcharge as well, and the overall price you pay would consist of a base fare, the fuel surcharge, and any additional taxes and fees. 

Fuel dumping refers to the art of “dumping” the fuel surcharge from the above calculus using a set of advanced booking tricks. Since the fuel surcharge can often represent 75% or more of the overall fare, this results in very substantial savings.

The Components of Airfare

A quick crash course on the basics of airfare is warranted here. Every airline fare you purchase is in fact a bundle of several different components. The final price you see on the airline’s website or on Expedia is the sum of all of these individual pieces.

ITA Matrix is a fantastic resource for learning more about airfare components. Let’s boot it up and examine this Air Canada fare from Toronto to Beijing, just to illustrate the different components that come together. 

When you pull up any fare on ITA Matrix, it’ll automatically show you the breakdown of how the total cost is calculated among each individual piece. For example, this total fare of $781.16 consists of $340 in “base fare”…

…$370 in carrier-imposed surcharge…

…and about $70 in various government taxes and airport improvement fees.

How Does Fuel Dumping Work?

Now, the taxes and fees are set by governments and airport operators, so there’s not much you can do about those. The base fares are set by the airlines themselves, and you’ll always have to pay those if you’re purchasing a ticket. 

But the carrier-imposed surcharge is the interesting part! Each airline has their own rules on how much gets charged and when this surcharge gets levied. In particular, there are rules that govern how the carrier-imposed surcharge behaves when you combine two or more airlines on the same ticket. These rules are far too complex and inaccessible for me to cover here, but you should just know that they exist.

Fuel dumping takes advantages of gaps and loopholes within these rules in order to create situations where the fuel surcharge does not get levied.

The classic example is the “3X” or “third strike”. When booking a roundtrip, you add on a third set of flights (after your outbound and return) that takes place after your original trip. 

Intended round-trip:

A – B
B – A

C – D

This third set of flights can be adjacent to one of the airports in your original itinerary, but it doesn’t have to be. In other words, it can be on the entirely opposite side of the world. Its only purpose is essentially to trick the airline’s ticketing system into “dumping” the original flight’s fuel surcharges from the equation, thus granting you significant savings.

You know how airlines sometimes publish fares by mistake, and everyone scrambles to book them before they’re gone? Well, you can think of fuel dumping as sort of forcing the airline to offer you their mistake fares on your own.

If we go back to the Air Canada example above, you can see that the carrier-imposed surcharge ($370) represents a significant portion of the overall fare ($780). If you were somehow able to drop that surcharge by adding a 3X onto the end of the itinerary, you’d potentially get half-price roundtrip tickets.

You probably have a lot of questions by this point, and I think a real-life example would help clear things up a bit.

An Illustrated Example

Back in 2016 I flew a fuel-dump fare from Boston to London via Lisbon on TAP Portugal. The original fare would’ve cost me around US$900 per person, but I booked it for US$227 instead by doing it like this:

See anything funny about this? That’s right, the 3X at the end is a domestic flight within Argentina, from La Rioja (IRJ) to Catamarca (CTC) on Aerolíneas Argentinas. I had no intention of ever taking this flight, but by booking it together with the TAP Portugal roundtrip, it caused the fare calculation to short-circuit and drop the fuel surcharge entirely. 

Intended round-trip:



Here are the ingredients of a good fuel dump, as told through this example:

  • A fare with a small base fare and a large fuel surcharge component: In this case, the original fare of US$900 was composed of approximately US$700 in fuel surcharges, plus US$200 in the base fare and other taxes and fees. Dumping the surcharge therefore results in huge savings. Other fares may be composed of higher base fares and lower surcharges, in which case a fuel dump wouldn’t be as effective in lowering the price.

  • A fare whose rules allow end-on-end combinations. You need to read the fare rules to ensure that your fare can be booked together with a 3X (or other combination) on the same ticket. The Fare Information section within ExpertFlyer will give you access to fare rules, and you’d look under “Combinations”. If it says “end-on-end combinations permitted”, then you’re indeed allowed to combine the fare with a separate fare (i.e., your intended 3X) and realize a potential fuel dump.

  • A 3X that dumps the fuel. Not any arbitrary flight can function as this 3X – you need to find the specific airlines and routes that cause the fare calculation to glitch out. The only way to find these, short of being informed by others in the know, is to do lots of searching and experimenting on your own. You also want to ensure that the base fare of the 3X is as low as possible – after all, it wouldn’t be a very good fuel dump if the 3X itself were as expensive as the fuel surcharge that’s being dropped!

In this case, the TAP Portugal fare had favourable rules, which allowed for end-on-end combinations. It had a good base-fare-to-surcharge ratio. And the 3X in question not only dumped the fuel, but also came very cheap at only US$27.

Therefore, the US$900 fare was reduced by US$700 once the fuel surcharge was dropped, and then the extra US$27 in the base fare of the 3X brought it up to US$227 in total.

Intended round-trip:

US$200 base fare & taxes
+ US$700 fuel surcharge
= US$900 total fare

US$27 base fare

What I booked:

US$200 base fare & taxes
+ US$700 fuel surcharge

+ US$27 base fare of 3X
= US$227 total fare

Other “Strikes”

The 3X is the classic example of how to dump the fuel surcharge. Other ways to “trick” the system include:

  • 1X (“first strike”): Instead of adding a third flight at the end, you add a flight at the beginning of the itinerary which also causes a fare miscalculation.

    The classic example is that you can often dump fuel surcharges on an airline ticket if you added a domestic Brazilian flight at the beginning, because the ticketing system is tricked into applying Brazil’s no-surcharge regulations to the entire ticket.

    The caveat is that unlike a 3X, you can’t skip a 1X – you must fly it first before commencing your actual intended journey; otherwise, your entire ticket may get cancelled if you no-show. Compared to 3Xs, 1Xs therefore tend to be easier to find but harder to use.

C – D

Intended round-trip:

A – B
B – A

  • Open-jaw / self-dump: Some airlines’ ticketing systems are so flawed that they can dump their own fuel surcharges when booking unconventional routings such as open-jaws (i.e., flying into one city and out of another on the same ticket).

    Remember, many of these systems are several decades old, and improving them would require a mammoth time and energy investment across the industry that simply hasn’t deemed worthwhile.

    A lot of the “mistake fares” you see on a website like Secret Flying are in fact “self-dumped” fares, in which a miscalculation occurred somewhere along the way and the intended fuel surcharge isn’t being levied.

  • Online travel agencies (OTAs): Examples of OTAs include Expedia, Travelocity, Cheapoair, etc. All OTAs have different ticketing systems in the back-end, and some of them are more susceptible to “forced errors” than others.

    Moreover, even within a certain OTA, different individual country websites (like,, etc.) may apply different rules in different ways, meaning that you might only be able to force a certain fuel dump via a certain country-specific website of a certain OTA.

Lastly, while most of the basic examples in the fuel-dumping world are illustrated through economy class fares, it’s possible to dump business class fares as well and attain international premium class travel at a spectacular discount. Alas, I don’t have any experience doing this, but I’m certain the most seasoned fuel-dumping experts out there are reaping the fruits of their labour in this way.

Should You Even Bother?

If this all seems convoluted and complex, that’s because it is. Let’s jump to the most basic question on your mind: how do I find active and working 3X combinations in order to book cheap fuel-dumped fares?

Unfortunately, because of how quickly the airlines would shut this loophole down if they found out, there’s no “easy” way to learn the art of fuel dumping. Instead, the only way forward is to first make sure you’ve fully grasped the basics (i.e., read this article over and over again very carefully), and then delve into the limited and extremely cloistered chat resources that are available online.

The most common starting point is the infamous “Trick It” thread on FlyerTalk, which has thousands of pages and 16,000 replies. It’s not a very newbie-friendly place – people speak in coded language in order to prevent their secrets from spilling into the wider world – and newcomers are generally asked to “read the thread” before jumping into the discussion. 

If you spend a few hours reading the last few pages, you can probably figure a few things out, but a sustained period of effort is usually required before you get to a level where you start finding your own 3Xs. Once you get to that stage, you can generally start “trading” 3Xs with other forum participants and continue building your knowledge from there.

I myself went through the early stages of this process back when I booked my last (and only) fuel-dump fare on TAP Portugal a few years ago. After a while, I realized that the time and effort spent simply wasn’t worth it. Indeed, I put my energy towards maximizing Miles & Points instead, and that’s gotten me to a very satisfying place in terms of my travel possibilities.

I strongly believe that the same would be true for most of you as well – all things being equal, your time is better spent trying to sharpen your expertise in travelling on points than in fuel dumping, since the rewards you’d get from the former are, in my opinion, much more substantial.

Nevertheless, the goal of this article was to give you an idea of this vulnerability in the airline ticketing systems that exists out there and that you could exploit if you wanted. If you find this stuff interesting, by all means go deep – who knows, you might get to the top of the fuel dumping game and never have to worry about award availability anymore! 😉


Fuel dumping is a creative and perhaps slightly underhanded way to score heavily discounted travel. By essentially using the byzantine nature of the global airfare ticketing system against itself, you’re able to piece together fares in a certain way and cause the fuel surcharge to disappear. It’s a very interesting concept to think about, but ultimately the secretive and sensitive nature of fuel dumping means that very few of us will ever get to take full advantage.

  1. Pascale

    It’s unclear to me how you would book such a trip online? For example, on Air Canada, if you choose multi-city, it wouldn’t work because your arrival city wouldn’t be the same as your departure city?

    1. Ricky YVR

      Fuel-dumped fares are rarely booked on the airline’s website. Most often, you try to force third-party OTAs like Expedia, Priceline, and Momondo to price out your itinerary and book through there.

  2. p

    Would you recommend not using your Aeroplan number when booking in case the airline figures out what you’re doing?

    1. Ricky YVR

      If you’re flying with an airline other than Air Canada, I don’t think it matters. If you’re flying Air Canada, it could be a prudent approach, although I don’t think it’d be an issue unless you’re flying dumped fares on a very frequent basis.

  3. Rich

    Wow, fantastic post on a fascinating subject. I’ve been in the points and miles game for several years now and fuel dumping is new to me. Very cool, thanks for sharing the info.

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