Navigate SFO Like An Expert And Get Through Security In Under 5 Minutes

a building with cars parked on the side
cars parked outside of a building

Last evening I drove over to SFO to drop off my wife for her flight, and was reminded of the trick that I use every time I fly out of SFO. Even though I’ve taught her the trick many times, it’s not something that will be top of mind if you’re not thinking about it. If fact, you’ll need to actively turn off your auto-pilot mode which follows the signs at the airport telling you where to go based on the airline you’re flying.

Most people will assume that when flying United you need to go to Terminal 3, and similarly when flying through International Terminal G then that’s where you need to head. The airlines serviced out of International Terminal G include:

  • Aer Lingus
  • Air Canada
  • Air China
  • Air New Zealand
  • ANA
  • Eva Air
  • Lufthansa
  • SAS 
  • Singapore Air
  • Swiss
  • United

But here’s a useful tip: there is an air-side walkway (after you go through security) that connects Terminal 3 and International Terminal G, meaning that you can use them interchangeably. Even if you are flying internationally, since there is no passport control, you can still go through security at Terminal 3 and then simply walk back to the international terminal. In the picture below, I’ve highlighted with the black arrow where the walkway is located – it’s just a 5 minute walk between Terminal G and gate 75, and about 15 minutes to gate 90 at the farthest end of Terminal 3.

a map of an airport

There are two security checkpoints at Terminal 3 – one for all passengers at the beginning of the terminal, and one for United elite passengers and those with TSA PreCheck located at the end of the terminal near the land-side walkway that leads to International Terminal G. This tip is most useful for general members flying United, but while most of you probably have elite status and/or PreCheck, it can still be useful since lines at that security checkpoint can be crazy during peak hours or when flying internationally.

Having flown United out of SFO 100+ times in the past few years, here’s my suggestion on which security checkpoint to try first, which varies based on the time of day:

  • Domestic Terminal 3: 10am-3pm and after 7pm. Most of the peak activity for international flights out of Terminal G are clustered around 12noon and late evenings, and international passengers typically arrive 2-3 hours before departure. For example, for late evening flights to Asia we’ve arrived at the international security checkpoint to find wait times of 30-45 minutes, exacerbated by the fact that you have leisure passengers and lots of children who take extra time to get through security. At this point, we simply walked over to Terminal 3, went through security in a couple of minutes, and walked back.
  • International Terminal G: Before 10am, 3pm-7pm. In terms of frequency, most people fly domestically far more often than internationally, so this will be the trick you use most. Especially on Mondays and Thursdays during peak consultant travel, this can save you a ton of time. Early mornings and early evenings are often a disaster at Terminal 3, so simply walk over to the Internationale Terminal which will be a ghost town, go through security, and walk back.

The advice above is most relevant when getting dropped off at the airport – but here’s a tip for those taking BART:

  • The BART exit leads into International Terminal G, always start here as there is no need to take the Air Shuttle over to Terminal 3. Check out the security line at the international terminal, and based on time of day walk through the land-side walkway to Terminal 3 if necessary.

Lastly, for those with United Club access, the lounge at Terminal 3 is always overcrowded. Time permitting, I always use the United Club at International Terminal G instead and rarely find it to be more than 50% occupied.

Hopefully these tips can help you save time next time you’re flying out of SFO!


  1. When I come back from overseas and after going through the custom, is there any shortcut to get to UA’s domestic flights to AUS quickly? Thanks!!

    1. Unfortunately not, the customs area leads into the “transfer” area where you drop off your bags and go through security which is probably the most efficient way through. Unless that line is crazy and if you have no bags, you could potentially exit to the arrivals hall, then go upstairs to the standard departure level.

Leave a Reply

Your email address will not be published. Required fields are marked *