I know you want to hear about a United/American mega-merger, but it’s not going to happen… other than that little teaser I stuck in the post title. Still, we talked about this on The Air Show this week, so you can absolutely get your fill. I don’t think this is trolling — though that’s certainly a nice side-benefit. There’s always a reason for things like this to reach the light of day, so come listen to our theories this week.
At United’s media day last month, the airline proudly put forth a slide noting that back in the day, it only had the largest local passenger share in one of its hubs: Houston. Today, it says it is number one in all of them except for Los Angeles. That is a big shift, but is it true? I pulled the numbers to find out, and regardless of the answer, it is clear that United is significantly growing its share in every one of its hubs with one notable exception.
To do this work, I pulled annual passenger share for United and the next largest airlines using the Department of Transportation’s Origin & Destination Survey data (DB1B/C) via Cirium. This looked only for passengers that weren’t connecting through the hub. The problem with this, however, is that the data that’s public is only domestic. So, I’ll present that here and then talk how international would likely change the results.
Let’s just do this in alphabetical order, shall we? That means we start in Chicago. The airline’s growth there will be no surprise to anyone since United has been crowing loudly to everyone who will listen about just how much local share the airline has gained. And the numbers certainly show that.
Chicagoland Local Passenger Share by Year

Data via Cirium
It wasn’t that long before the pandemic that American was number one in Chicago, but now it’s no contest. American in fact had slipped below Southwest and its Midway operation. Of course, 2025 was the year American realized it was going to lose a lot of gates if it didn’t snap to it, so it started pouring capacity into the market. That raised its local share but it looks like it largely took it at the expense of Southwest. United just keeps growing.
If we were to include international, United’s lead would only grow. In full year 2025, United more than doubles the number of international seats that American has in the market. If we include joint venture partners, it’s only slightly less than double. So if anything, this is understating United’s gains.
Now let’s move on to Denver where international flying is more of a rounding error.
Denver Local Passenger Share by Year

Data via Cirium
This has been a fight between United and Southwest, but United has certainly taken a much greater share of the pie in the last few years. It is now the clear number one in the market. This was such a hot topic in previous years, but now it’s not even worth discussing further.
What if we head down to Houston? Remember, this is the one market where United was in first place before already.
Houston Local Passenger Share by Year

Data via Cirium
And it’s still in first place. What’s interesting here is that United hasn’t changed all that much since 2019, but Southwest has fallen off more there. We are talking different airports here, of course, but Southwest has been losing share to ULCCs Spirit and Frontier and also Delta while United keeps growing. Oh, and once you consider United’s robust Latin flying from here, there isn’t a contest.
But if you want a contest, we can look at my homebase, the Los Angeles Basin. This is by design a market that can’t be dominated by any one airline, and that shows itself in the data.
Los Angeles Basin Local Passenger Share by Year

Data via Cirium
You might be surprised to see that Southwest is so much bigger than the rest, but remember, we are talking about the metro area. Southwest may not be as important at LAX but it dominates all the other local airports. Number two was American before the pandemic, but once it shut off its Pacific hub, that changed quickly. Delta is number one now. If you were to add in international, I’d assume it might help Delta pad its lead on second place a little. But to win the metro area, you still have to beat Southwest and that won’t be easy to do for United.
And then there’s New York. New York’s results may look somewhat shocking at first glance.
New York City Local Passenger Share by Year

Data via Cirium
Look at Delta pulling away from United to dominate New York over the last couple of years. This fits with what we saw at LaGuardia where Delta really boosted local traffic, enough to win it a Cranky Network Award this year. But do keep in mind that capacity was reduced significantly in Newark thanks to ATC issues leading to gridlock. So that had to hurt United.
But again, this is missing international. Yes, both airlines have huge international operations in New York, but United actually skews more toward international than Delta. Delta and joint venture partners have a total of 27 percent of their seats going outside the US while United and partners are north of 35 percent. When we adjust for that, it ends up being neck and neck even after Newark reductions.
I’m sure there’s some way for United to cherry-pick the numbers that help the claim it is number one, but unlike in other markets, this is no runaway. Delta and United are still both locked in a dead heat.
What about San Francisco? Oh that one is like watching a hockey stick.
San Francisco Bay Area Local Passenger Share by Year

Data via Cirium
Alaska has turned away from more traditional markets from San Francisco since the Virgin America merger. It’s no surprise it keeps losing share, but what about Southwest? Southwest has its massive Oakland hub along with a substantial San Jose operation, but it has been pulling down Oakland in favor of Sacramento as of late. That may very well change, but in 2025 United and Southwest were neck-and-neck domestically. That means with international baked in, it’s no contest.
And finally, we look at DC. Was United including Baltimore or not? It’s hard to say for sure, but it’s certainly much easier without it.
Washington/Baltimore Local Passenger Share by Year

Data via Cirium
I think the key finding here for United is that its Dulles operation has now surpassed American’s National operation in terms of local passengers carried. That is quite the milestone. Southwest is still far ahead, but again, remember, we are talking domestic market only. A quarter of United’s seats in DC fly internationally whereas for Southwest it’s less than three percent.
The reality here is similar to New York where overall it’s going to be very close between the two airlines. That’s a substantial change from pre-pandemic when it wasn’t even a contest, but whether United is truly the king… that’s debatable. Then again, if United isn’t counting Baltimore, well, then that’s an easy victory to claim.
I think it’s important to note that just because you have higher local share doesn’t mean that you can declare sunshine-and-rainbows. After all, what if connecting traffic were to carry a much greater premium? Is it worth buying local share by becoming more competitive? I’m not saying that’s what is happening here, because I’m not going down the revenue road today. But United’s financial results do speak for themselves.
One thing that has changed is the importance of the credit card. And to get more credit card sign-ups, you want to be as useful as possible to the local market in the hub. United certainly gets that and has made strides in improving relevance in every part of its network.

