United Airlines has an 'expert mode' -- Here's how and why to use it

You might think airline tickets just come in economy, premium economy, business-class and first-class fare buckets. However, the reality is that each of those classes is further subdivided into different fare classes that are given distinct letter codes designating them as anything from the cheapest basic economy fare all the way up to full-fare first class. This is not to mention seats set aside for mileage awards or upgrade redemptions.

If United MileagePlus is one of your main airline loyalty programs, knowing which fare class your ticket is booked in can be important for a few reasons but the best way to determine which fare classes are available is to activate what's called: United expert mode.

Once enabled, United Airline's "expert mode" allows you to search for airline tickets by specific fare classes, including seats that are available for award bookings and confirmable upgrades.

Fare class basics

Not all fare classes earn miles the same way, especially with United's airline partners, and you might earn fewer (or no!) miles when purchasing discounted fare classes than you would with full-fare tickets.

But perhaps more relevant to everyday use is that with expert mode you can search award-seat inventory by fare class -- meaning you can determine whether there are award seats available on certain flights, and also how many there are. This is also how you can see which tickets might be upgradable using PlusPoints or miles.

The best way to figure out the fare class availability on your United flights is by using the airline's so-called expert mode. Here's how you can use it to find the seats you want.

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Turning on United expert mode

To enable expert mode, go to United.com and log in to your MileagePlus account. Navigate to your account homepage and find the "Profile & Preferences" drop-down.

From there, click, "Preferences & settings," then scroll down to where it says "Enable expert mode," and make sure the box is checked.

Click "Save," and you should be all set.

Just note that you must be logged in to your account so that expert mode is enabled when you perform a flight search.

Related: Decoding United's revenue, award and upgrade fare classes

United award and upgrade fare classes

Now for the more complicated part.

United has dozens of fare classes to denote both paid tickets, award tickets and upgrades. While this can be confusing at times, it can also help you identify whether you’ll be successful in your quest to snag a better seat for your trip. For now, we're just going to focus on two types of fare classes: upgrades and awards.

Upgrade fare classes

If you want to purchase a ticket and then upgrade it -- whether using PlusPoints as a United elite or just miles as a regular MileagePlus member -- look for tickets with these three fare codes:

• PN denotes upgrade availability for the program's invite-only top-tier Global Services members. It is also where instant 'full fare' upgrades can pull from for Y/B/M fare classes for 1K and Global Services members.
• PZ is used for most other upgrades, including mileage upgrades and upgrades with PlusPoints for travelers who aren’t Global Services. It’s also where instant, ‘full fare’ upgrades pull from for Y/B fare classes when booked by for Silver through Platinum members.
• RN is used for upgrades to United’s Premium Plus cabin.

Just because upgrade inventory appears in your search doesn’t guarantee that you’ll be able to upgrade, as there are many added restrictions of which you should be aware. You’ll need to check United’s upgrades overview page, which lists which members are eligible for which types of upgrades and which fare classes apply. Rather than go into exhaustive detail here, we have a comprehensive guide to upgrades on United and another on using PlusPoints for upgrades.

Related: How to get United Airlines upgrades using miles

Award fare classes

United uses nine (yes, nine) different fare codes for award tickets.

Polaris (business class)

• JN – Everyday awards for elites and credit card holders.
• ZN – Everyday awards for all other customers.
• IN – Saver awards for elites (since they have access to expanded award inventory).
• I – Saver awards for all other customers and partner redemptions.

Premium Plus (premium economy)

• ON – All awards (variable pricing).

Economy

• YN – Everyday awards for elites and credit card holders.
• HN – Everyday awards for all other customers.
• XN – Saver awards for elites and credit cardholders.
• X – Saver awards for all other customers and partner redemptions.

Note that these fare buckets are consistent, but the carrier’s variable award pricing is not, so you’d need to search for your exact flight (while logged in) to see how many miles you’d need to redeem. That pricing varies not only by day and route but also by whether you have elite status or a United credit card. Those members often pay less for some awards.

If you're searching for award tickets, chances are you'll want to look for the most basic types of awards in each cabin -- those saver-level ones available to the general public.

Related: These are the best United credit cards

Using expert mode

Let’s see how all this works on the site. For the most part, you’ll probably be looking for I business-class awards, and PZ upgrade availability on flights so you can confirm upgrades using miles rather than putting yourself on the waitlist and working through the byzantine hierarchy of United’s upgrade priority.

In order for expert mode to display available award classes, you must search for paid tickets rather than award tickets.

San Francisco to Honolulu with upgrade and award space

As a quick example, here’s a flight search from San Francisco (SFO) to Honolulu (HNL) in mid-November. When the results come up, click on the "Details" tab for a particular flight, and that will display all the fare classes.

On this flight, you’ll notice there are seven PN tickets, meaning there are seven seats currently available for Global Services or instant upgrades. There are three PZ tickets for elites to snag with PlusPoints and those without elite status to upgrade using miles. There are also two I-fare tickets for saver-level business-class awards, and nine X economy saver awards.

However, you'd be in a better position to upgrade if a PZ or PN fare became available, depending on your elite status, by booking into a higher economy-fare class

You may also notice that this search is showing N-fare tickets in basic economy, which are not upgradable. This is an important example because the fare class you book will indicate whether you can upgrade a flight with miles or PlusPoints, and it may also determine the number of miles you’d need to use or the copay you’d need to fork over to do so as a non-Premier member. You might want to go so far as pricing out various individual fare classes to bring down your mileage and cash outlay for an upgrade.

Look for individual fare classes using advanced search

For a little help figuring out which fare class might be your best bet in terms of paid fares versus upgrade mileage and copays, scroll back up to the top and click on the “Advanced Search” link. There’s a section of the search page that allows you to search by specific fare classes.

Unfortunately, it won't let you search for award or upgrade classes. However, if you put “G” in that box for a discounted economy ticket ...

… it pulls up the following results.

But for a better shot at an upgrade using fewer miles or PlusPoints, you'd want to pick a higher fare class, like W. Let's take this example from Houston (IAH) to Honolulu. There are higher fare classes available, but no upgrade space for now, so you'd take a gamble by booking. However, you'd be in a better position to upgrade if a PZ or PN fare became available, depending on your elite status, by booking into a higher economy-fare class.

Washington to London with upgrade and award space

Finally, here's an international example with flights from Washington, D.C. (IAD), to London Heathrow (LHR).

As you can see, there is upgrade space galore, though no saver-level business-class awards for the general public (there are IN awards for elites with access to expanded availability). This would be an instance where you'd want to purchase an eligible economy fare (of which there are plenty listed here) and then use PlusPoints or miles to upgrade to business class.

Bottom line

United’s expert mode isn’t necessary for the majority of flyers just looking for cheap airfare on a one-off flight. When it comes to finding award tickets and upgradable tickets, being able to see the fare buckets available on specific flights can be invaluable.

Sure, there are a lot of alphabetical codes to keep track of. But putting in a little effort and using United's expert mode can pay off if you hope to purchase tickets and then use your miles or PlusPoints to upgrade. Not only that, but by paying attention to the award classes, you can also determine whether there will be enough seats for your entire party to fly before actually trying to book, which can come in especially handy if you need to transfer points into your MileagePlus account for an award.