Decoding United's revenue, award and upgrade fare classes

We know United's classes of service as business or first, premium economy and coach. But reservations systems don't label bookings in the same way at all — instead, those same cabins are J, O and Y, and a wide variety of other letter designators as well.

Take the Polaris cabin below. Everyone booked there gets to select whichever seat they wish, even though 1A might be flying on a ticket booked in "I" class (saver award) and 8L might be flying in full-fare J. Decoding those letters reveals not only whether a flyer booked their seat with miles, but roughly how many miles they used — and if they're flying on a revenue ticket, we can even get a general sense of how much they paid.

For frequent flyers, fare classes are the key to mileage earnings and elite credits, too — a basic economy customer ("N" class) will earn far less than a business traveler on a full-fare "Y" ticket, for example.

You'll also need to pay attention if you're hoping to use an upgrade certificate to move from economy to Polaris biz — you'll use 40 PlusPoints if you book a flight in the "W" fare class or higher, while less expensive fare classes require double that amount.

These codes come into play when it comes time to change a flight, too — if only a higher fare class is available, you'll likely need to pay the difference in price, even if taking advantage of United's same-day change. In other words, these are definitely some letters you'll want to add to your vocabulary. When it comes to United, let's see how they break down.

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Revenue Fare Classes

To really make sense of this alphabet soup, I recommend pulling up United's site and following along. But first, you'll want to head over to your profile page and enable Expert Mode, so you're able to see the full list of fare classes whenever you search for a paid itinerary, just as you can below.

The list of "available fare classes" above includes paid tickets, upgrades and awards, all mixed in together. Starting with revenue fares, here's how it breaks down.

First/business class

J - Full fare
C - High fare
D - High fare
Z - Discounted fare
P - Deep-discounted fare

Premium Plus

O - High fare
A - Discounted fare
R - Deep-discounted fare

Economy

Y - Highest full fare - regional instant upgrades for all elites
B - Full fare - regional instant upgrades for all elites
M - High fare - regional instant upgrades for Premier 1K
E - High fare
U - High fare
H - High fare
Q - Discounted fare
V - Discounted fare
W - Lowest Polaris upgrade-eligible fare
S - Deep-discounted fare
T - Deep-discounted fare
L - Deep-discounted fare
K - Deep-discounted fare
G - Lowest discounted fare
N - Basic economy - no changes permitted

Upgrade Fare Classes

Next up are the upgrade fare classes — you can move up from economy to either Premium Plus or Polaris business class, and from Premium Plus to business class as well. As outlined above, passengers booked in the "W" fare class or higher can redeem 40 PlusPoints to move to Polaris business class on international flights, while tickets booked in S, T, L, K or G classes need 80 points.

All paid Premium Plus fares are eligible for Polaris upgrades at 30 PlusPoints, and all regular economy fares are eligible for Premium Plus upgrades at a rate of 20 PlusPoints.

First/business class

PN - Global Services mileage and PlusPoints, and instant upgrades for all other customers
PZ - Platinum and Premier 1K PlusPoints and all mileage upgrade awards

Premium Plus

RN - Upgrades for all members

Award Fare Classes

Finally, it's on to the awards. There are a total of nine fare classes for mileage tickets, and just as with paid flights, the rates can vary wildly from one code to the next. If you're hoping to see fare classes when searching for an award, you'll actually need to begin with a revenue search — individual codes won't appear if you click "book with miles" on United.com.

First/business class

JN - Everyday award for elites and credit cardholders
ZN - Everyday award for all other customers
IN - Saver award for elites
I - Saver award for all other customers and partner redemptions

Premium Plus

ON - All awards (variable pricing)

Economy

YN - Everyday award for elites and credit cardholders
HN - Everyday award for all other customers
XN - Saver award for elites and credit cardholders
X - Saver award for all other customers and partner redemptions

Bottom Line

Many frequent flyers have likely committed most of these fare classes to memory — from paid tickets to upgrades to awards, knowing the meaning of each code empowers you to book, change and earn credit from flights as effectively as possible. While you don't need to memorize them all today, I do recommend enabling Expert Mode on United's site, giving you access to all of this incredibly useful data whenever you log in, be it on the airline's website or its new mobile app.

Featured photo by Zach Honig/The Points Guy.