Understanding San Francisco Airport Initials: SFO
Airport codes have gotten complicated with all the strange abbreviations flying around that seem to make zero logical sense. As someone who has traveled through dozens of airports and always wondered why the codes rarely match the city names, I learned everything there is to know about why San Francisco uses SFO. Today, I will share it all with you.
Why SFO?
Probably should have led with this section, honestly. The International Air Transport Association (IATA) assigns these three-letter codes, and every single one has to be unique worldwide — no duplicates allowed across the entire planet. SF was already taken. SFA was already taken too. So San Francisco got SFO, with the “O” making it distinct from every other airport code in existence.
This happens way more than you would think. LAX is not LA-X for some mysterious cool-sounding reason. It is just that LA was taken by another identifier, so Los Angeles added an X to make it work. Chicago O’Hare is ORD because the airport used to be called Orchard Field back in the day. These codes accumulate history like layers of paint on an old building, and each one has a story. That is what makes airport codes endearing to us aviation nerds — they are these tiny time capsules hiding in plain sight on every boarding pass.
The Airport Itself
SFO sits 13 miles south of San Francisco proper, which means you are actually in San Mateo County when you land. I remember being confused by this the first time I took a rideshare from the airport and watched the GPS show me leaving San Francisco before I had even arrived. The airport has been operating since 1927, starting as Mills Field on what used to be a cow pasture. From cattle to 747s in under a century — pretty remarkable transformation.
Four terminals now handle the traffic. It is a major international hub with extensive connections to Asia and Europe that make it one of the busiest airports on the entire West Coast. About 50 million passengers come through in a normal year, and it shows during peak travel seasons when the terminals get genuinely packed.
Getting There and Away
BART runs directly to the airport, which is a huge advantage over most American airports that leave you stranded without a car. The train takes about 30 minutes from downtown San Francisco and costs just a few dollars each way. During rush hour, BART beats sitting in 101 traffic by a wide margin — I have done the drive and the train and the train wins every single time unless you are traveling at 3am.
Car rentals, taxis, Uber, and Lyft all work the usual way with designated pickup areas. Parking exists in various price tiers depending on how long you are gone and how far you are willing to walk or take a shuttle. Long-term parking fills up during holiday weeks, so book ahead if you are leaving your car.
The Fog Problem
SFO has a fog problem that everyone who flies through there learns about eventually, usually the hard way. The airport’s runways are close together and parallel, which means when visibility drops below a certain threshold, they can only land planes on one runway at a time instead of two simultaneously.
This creates delays. Lots of delays. Morning flights out of SFO are notorious for getting pushed back while everyone sits at the gate waiting for the marine layer to burn off. I have had multiple flights delayed an hour or more because of fog that looked like it would never clear. By afternoon, things usually open up and the delays cascade through the rest of the day’s schedule.
Oakland (OAK) and San Jose (SJC) have significantly better weather patterns. Frequent travelers to the Bay Area sometimes book through those airports specifically to avoid SFO’s fog delays, especially for morning departures when the marine layer is thickest. Something worth considering if you have flexibility in your booking.
What’s Inside
SFO has decent food and shopping for an airport. Not amazing, not terrible — somewhere in the respectable middle. The international terminal has the best options by far, with more variety and quality. Domestic terminals are more grab-and-go focused, which is fine for a quick bite but nothing you would write home about.
Free Wi-Fi works throughout the entire facility. Charging stations exist but get crowded during peak hours — bring a portable charger if you can. Lounges are available through airlines and various credit card programs for those who have access.
One genuinely unique thing that sets SFO apart: it has an actual museum. The SFO Museum is accredited by the American Alliance of Museums and puts rotating exhibits throughout the terminals. Aviation history, Bay Area culture, contemporary art installations. It is something real to do besides staring at your phone during a layover. I have killed an hour browsing exhibits more than once and actually learned something each time.
Environmental Programs
San Francisco takes sustainability seriously as a city, and the airport follows suit with real initiatives. Electric vehicle charging stations in the parking structures, comprehensive recycling programs, water conservation efforts throughout the facility. They have made public commitments to carbon reduction, which you will see reflected in signage around the terminals.
Whether this matters to you depends on your personal priorities. But it is part of what makes SFO feel like a Bay Area institution that reflects the values of its community rather than a generic airport that could be anywhere in America.
The Short Version
SFO is San Francisco International Airport. The code is SFO because the more obvious alternatives were already taken by the time they needed one. It is a major hub with solid transit connections but persistent fog delays that can wreck your morning schedule. BART is your friend for getting in and out. Morning flights are risky — book afternoon if you can. And the museum is actually worth checking out if you have time to kill between flights.
Now you know more about SFO than most of the 50 million people who fly through it every year. Use that knowledge wisely.
