US entry date based on aircraft arrival time?
 

If I land at SFO at 9 p.m. and the customs lineup is delayed so I don't exit customs until just after midnight, do I get recorded by US CBP as having entered the US the next day?

Likewise, if my flight out of LAX is, say, 11.35pm on a Sunday, and it's delayed by an hour and it hasn't left the gate, do CBP record it as a Sunday departure, or Monday? An important distinction if you're on the verge of overstaying your ESTA/Visa.

Because overstaying a visit can have signficant legal implications for both of you, and although this is Flytertalk, your best action is not to rely on anonymous people posting on an internet chatboard to provide accurate answers to your questions but rather, you should seek definitive information directly from CPB (as provided from CPB website):

1. You can contact the CBP Information Center (CIC) at 877-227-5511 (00+1+202-325-8000 for international callers).

Having said that, the follow FAQ https://i94.cbp.dhs.gov/I94/#/faq has the following: [emphasis added]

When I query my name in the View Compliance tab, what does days remaining in the United States mean?

The days remaining in the United Sates are the days you have left on your period of admission as listed on your current Form I-94. This number is calculated from the current day until the last day of your admission period. You must depart the United States, unless you have a pending or approved petition or application with USCIS that allowing you to remain, by 11:59 PM Eastern Time (ET) on the last day of your admission. You can find the admit until date on your current Form I-94, which is available on the “Get Most Recent I-94” tab of this website or through the CBP One™ mobile application.

Now, to me, that does not seem entirely practical for folks on the west coast and I suspect CBP actually means 11:59 PM local time. And I suspect they are authorized to use discretion for situations in which there are travel delays that are beyond the control of the visitor.

But you should contact CBP directly to find out from the horse's mouth, so to speak.

CBP does indeed mean 11:59 PM Eastern Time, not local time. The I-94 system uses Eastern Time for determining dates, no matter where in the US you enter/exit from, no matter how practical it seems for folks on the west coast.

For ESTA, the only "discretion" is through a grant of Satisfactory Departure from USCIS or CBP. If you haven't applied for Satisfactory Departure and you exceed the 90 days, the system automatically cancels your ESTA and you're no longer eligible for the Visa Waiver Program — you'd have to apply for a visitor visa to visit the US again. For visa holders, your visa gets automatically cancelled, and you'd also need a new visa to return to the US again.

If you land at SFO at 9pm, you'll be recorded as arriving the next day no matter how long you spend in the customs line, since it's already 12am ET. If you depart from LAX at 11:35pm on a Sunday, it'll be recorded as a Monday departure since it's already Monday in Eastern Time.

While we have cleared up what time zone applies, the questions raised in the original post (OP) (arrival date -- landing time versus CBP) and in Posts # 2 to 4 (departure date -- airline schedule versus actual take-off) have not been definitively answered.

It seems pretty clear that arrival is based on CBP clearance time.

For departure, airlines routinely use the scheduled departure time for crediting a mileage earning date. So if a flight departs early or late, the original boarding pass remains valid. CBP has no record of when each aircraft's wheels left the runway, and therefore presumably would rely upon a boarding pass / airline records.

However, if a flight is canceled and rescheduled to a new date (Eastern Time), it would be hard to argue one had still "departed" the United States on the original date. In such circumstances, if the 90-day period had been exceeded, one would be well advised to seek and obtain a grant of Satisfactory Departure from USCIS or CBP to maintain ESTA, VWP, and visa eligibility.