---
title: "SFO is which airport? San Francisco"
description: "SFO is San Francisco International Airport in San Francisco, United States. Where the code comes from, and the codes it gets mixed up with."
url: https://atoneplace.net/airport/sfo/
site: "At One Place"
---

# What airport is SFO?

**SFO is: San Francisco International Airport**

San Francisco, United States

## Why the code is SFO

San FranciscO — the first two letters plus the last.

The airport authority or a contemporaneous record states this directly.

## The airport

- **IATA code:** SFO
- **ICAO code:** KSFO
- **Airport:** San Francisco International Airport
- **City:** San Francisco, United States
- **Opened:** 1927
- **Code origin:** Documented

It is built on fill in San Francisco Bay and sits about four metres above sea level, which makes it one of the most sea-level-exposed major airports in the United States. Its two pairs of parallel runways are only 230 m apart, too close for simultaneous approaches in poor visibility, which is why SFO delays cascade through the entire domestic network whenever the fog comes in.

## The other code, KSFO

Every airport has two codes. The three-letter IATA code, SFO, is the one on your boarding pass and your luggage tag, and it is assigned for commercial use. The four-letter ICAO code, KSFO, is the one pilots and controllers use, and it is assigned geographically: the first letter or two identify the region, so every airport in the same part of the world shares a prefix. That is why KSFO looks nothing like SFO.

## Common questions

### What airport is SFO?

San Francisco International Airport, in San Francisco, United States.

### Why is San Francisco's airport called SFO?

San FranciscO — the first two letters plus the last.

### What is the difference between SFO and KSFO?

SFO is the IATA code, used commercially — tickets, timetables, luggage tags. KSFO is the ICAO code, used operationally by pilots and air traffic control, and assigned geographically by region.

## Related pages

- [United States](https://atoneplace.net/country/united-states/)
- [The flag of United States](https://atoneplace.net/flag/united-states/)
- [Airport codes in United States](https://atoneplace.net/airport/in/united-states/)
- [What airport is JFK?](https://atoneplace.net/airport/jfk/)
- [What airport is LAX?](https://atoneplace.net/airport/lax/)
- [What airport is ORD?](https://atoneplace.net/airport/ord/)
- [What airport is ATL?](https://atoneplace.net/airport/atl/)
- [What airport is MCO?](https://atoneplace.net/airport/mco/)
- [What airport is DFW?](https://atoneplace.net/airport/dfw/)
- [What airport is EWR?](https://atoneplace.net/airport/ewr/)
- [What airport is LGA?](https://atoneplace.net/airport/lga/)

## Sources

- OurAirports — OurAirports (https://ourairports.com/data/) [Public domain]