By Liam 
The logic behind a hidden city ticketing opportunity is theoretically simple. A nonstop flight to a destination you’re planning to go to happens to be more expensive than a flight which uses this same destination as a stopover. So, you book a ticket which connects through the city you actually want to go to and get off permanently instead of boarding the connecting flight. Confused? Let’s just run through an example.
A Hypothetical Example
Let’s say I want to leave from Madison, WI on January 14th and go to San Francisco. I do a quick search for a United flight and (as of the time of writing) I see that a nonstop flight is an expensive $350.
I instead try to book a flight which stops in San Francisco and has a different final destination to save money. I come across a trip to Las Vegas which includes the exact same flight to San Francisco for only $107! So, I get off at SFO and don’t board the final flight to Vegas.
It sounds incredibly simple,but these opportunities are not the easiest to find. There are also some guidelines to follow if you choose to pursue such an itinerary. This trick is legal, but airlines absolutely detest it. A disclaimer is necessary for that reason.
1. Do not provide your frequent flier number when flying on a hidden city flight and always book hidden city tickets as one ways. Although rare, If the airline catches on to this they may ban you from flying with them.
2. Absolutely do not check a bag. If your flight from Chicago is ticketed to San Francisco and you get off in Denver, your bags will be going to SFO without you. To ensure you don’t have to check a bag, bring a backpack or a carry on of a similar size.
3. There is always a risk that due to weather or another factor, the flight is redirected through a different connecting airport instead of the one you actually want to go to.
If that doesn’t scare you off, here are the best ways to find these itineraries:
Skiplagged
Skiplagged is a travel website completely dedicated to these types of itineraries. All you have to do is put in your city of origin and ideal destination and they’ll find the cheapest way to get there with or without hidden city ticketing.
Google ITA Flight Matrix
You can also identify these opportunities by using routing codes in the ITA Flight Matrix. In the Destinations section, I put in the airport codes of the busiest 100 airports in the US. In the routing codes section, you should put the airport you actually want to end up at.
The results ended up being the same:
Common Sense?
If you play around with the cities on Google Flights a bit, you will probably be able to find these itineraries on your own without too much trouble. The cities this works best with are big airline hubs which have flights to a lot of smaller destinations. Newark, Houston, San Francisco, LA, Denver and Chicago are probably the best cities to try this with on United. Atlanta, Detroit, New York (JFK) and Minneapolis should work well for Delta. For American, try Charlotte, Dallas, and Philadelphia.
Remember, this post should not be construed as an endorsement of these itineraries, as again, they come with considerable risk. You’ll have to figure out on your own if the savings are worth potentially losing your bags. It might be unlikely, but you could get banned from an airline if you abuse this trick too much. During your skipped connecting flight, you could be delaying the plane you’re supposed to be on, as flights will often wait for connecting passengers. If none of this weighs on your conscience, use at your own risk.