Many people get the notion that if they hold purchased First Class airline tickets, that they automatically get access to respective airline lounges/clubs. That is not necessarily the case, especially within the U.S.
This article speaks to the major U.S. based airlines, as all other airlines around the world have different airline lounge access rules, although most are very much similar.
Firstly, all purchased Alaska Airlines first class tickets do get access to their Board Room lounges.
As well, all Hawaiian Airlines first class tickets get access to Premier Club lounges in respective Hawaii island airports (they don't have lounges in the mainland). International business class get access to the better Plumeria lounge.
I don't believe much of the other so called lower tier airlines have any lounges at all, which include Southwest Airlines, Frontier, Spirit, and JetBlue. That's not surprising as they operate on a low cost business model.
As for the 3 major U.S. domestic airline: United, Delta, and American ... they operate all in the similar sense that holding a domestic, First Class ticket within the US 50 states, does NOT give you automatic access to lounge, with a few exceptions obviously.
Note that many of these airlines that operate the busy transcontinental routes, usually between LAX and JFK or SFO and JFK get access to lounge if you hold a First Class ticket. American also gives access for those traveling LAX and MIA on first class ticket.
I'm going to use the example of my recent travel from San Juan, Puerto Rico to Kahului, Maui, Hawaii.
It's interesting, that a long 11 hour flight with United Airlines from Newark, NJ to Honolulu, HI in first class does NOT give you access to the United Club lounge. That sounds pretty ridiculous considering the cost of the ticket and how long the flight is. But because Hawaii is considered part of the US 50 states, then that 11 hour flight is a domestic flight.
I'll use United as example, they consider access to be an:
A. International destination
B. United Business Class (which is majority of routes outside of the 50 US states)
So using my example, its interesting since Puerto Rico is a US territory .. so technically its a domestic flight ... however for purposes of access to the United Club ... United Airlines considers Puerto Rico part of the "Caribbean" territory ... and therefore is international. You'll know for sure if your flight is international if on the boarding pass, it lists it as INTL at the top.
Because the journey starts off international, even if you have connecting flights that are all domestic US ... you still get lounge access for the entire journey! So that means I get access to United Club at Chicago and Los Angeles, even though the flight between ORD to LAX and LAX to OGG are all domestic flights.
With long layovers and airports super crowded ... it pays to know if you have lounge access or not. It's really NOT worth purchasing first class domestic tickets as they are usually overpriced and you get no lounge access.
There are some ways around it like getting the American Express Platinum card so you can get Priority Pass lounge access, Amex Centurion Lounge access, or Delta Airlines lounge access (by having a Delta ticket). As well, there is Chase Sapphire Reserve card as well.
