24 hour testing requirement for before arrival and west coast time difference

Edited: I did take a look at Greece's requirements, and some of what I posted here is wrong. Follow-up post below should point you in the right direction.

Disclaimer: I have not looked at Greece's requirements specifically (I'm not going there anytime soon). That said, most time-based test requirements that I have seen usually only reference your departure time -- the time your first flight departs (assuming you are flying on a single itinerary), not your arrival time (and for the exact reason you cite: because doing the math gets challenging, and airport staff have better things to do than try and figure out what time the time difference between Athens and Cucamonga is).

Two suggestions: Go back and read the requirements for Greece carefully -- hopefully they reference your departure time, not your arrival time. Also hopefully: you are on a single ticket, and you won't be spending more than 23 hours flying to Athens, you're not on some Frankenticket that has you spending 2 days to get there with 5 long layovers. Your mental calculations may be unnecessary.

Finally, more good news: If the requirement to enter is just a mere Rapid Antigen test (really? many jurisdictions require a PCR test, which is much more challenging to get done quickly), you can knock out a rapid antigen test in 15 minutes (for free, if you play your cards right) while waiting to board - though most "test requirements" specify you must provide provide documentary proof of a negative test, usually from a certified lab that performed the test; just bringing the negative test gizmo won't cut it). Rapid antigen tests are the quick 'n cheap ones that the federal government is currently distributing, and are quite easy to get currently. Easy peasey lemon squeezey. Maybe too easy. I'd double check the requirements and make sure you have the details right: are you sure you don't need a PCR test?

OK, I stand corrected: just checked the US Consulate/Embassy in Greece, their last update just a few days ago. Here's the requirements:

PCR Test Requirement for Entry to Greece: Effective Sunday, December 19, 2021, travelers to Greece will be required to present a negative COVID-19 PCR test taken within 72 hours or a laboratory rapid antigen test taken within 24 hours of arrival to Greece

So no, maybe not so easy peasey. And yes, the time is calculated based on your arrival time, so you will need to do some math. The test requirements is a PCR test within 72 hours, OR a LABORATORY antigen test (no self-test with the free/cheap home test) within 24 hours -- unfortunately, all time references are to your arrival time. You're going to need to be careful about the test details and sweat the timing (unless of course the rules change between now and May, which is certainly possible).

What is your end-to-end elapsed travel time, from first flight departure to arrival time in Athens (your flight booking usually shows this number - total travel time)? Using that number, count back from the arrival time, subtract the time difference (don't forget possible daylight savings time shift here/"summer time" shift there). You will need your tests results in hand, with a time/date stamp that meets the Greek requirement, (probably) in order to board your flight (airlines may check to see if you have your required documents at check-in, although some may not).

The next complication: what day of the week are you leaving on? If it's a Monday, this may further complicate things (there are fewer test options over the weekend, and many test options will tell you it takes "one to three days" to get results, adding more uncertainty). You will need to choose a test option that gets your results to you in time.

Sorry, this may not be so easy peasey after all. (I went through the same mental gymnastics last summer, and ended up getting 3 PCR tests, I received one test results just hours before we departed, another when we had just boarded our first flight, and the next the following day...yes, it can be stressful). Good luck.

It's a 10-hour time difference between LA and Athens, summer and winter. The time difference shouldn't matter in calculating how long before arrival your test happened. So arriving in ATH at 3 pm local time would mean an antigen test taken after 3 pm the preceding day, which would be 5 am in LA. Make sense?

This potential for confusion is one of the reasons the US requires a test taken no sooner than the day before entry, rather than 24 hours. (Before Omicron it was in the three days before entry rather than 72 hours as many people assumed.)

Have you looked at the website of the Greek health ministry? That would be the most authoritative source. Unfortunately, for some countries the translation to English can add to confusion.

I wouldn't worry at the moment. https://travel.gov.gr/#/

Currently:

Travellers arriving in Greece, during the period from 24.01.2022 until 07.02.2022, regardless of nationality, their vaccination status or proof of recovery, are required to display a negative molecular test result (PCR) for Covid-19 performed up to 72 hours before the scheduled arrival or a negative Rapid Antigen test result for Covid-19 performed up to 24 hours before the scheduled arrival. The test result must be issued by a certified diagnostic center in Greek, English, French, German, Spanish, Italian or Russian and must include the name of the passenger as registered in the passport.

So, you have to wait until 7 February to learn more (or if they're extending the current requirements).

But, a neg PCR is doable - for Wednesday at 5:30 pm arrival, take by Sunday, 530 pm GREECE time, whatever that translates to in LA.

Yes, the rules could certainly change by May, hopefully less stringent because Covid will be less of a risk by then.

I'm sorry about the confusion over time zones. I was offering a hypothetical without looking back at the actual times in the original post. Using those actual times, arriving ATH Wednesday at 5:30 pm would mean getting tested in LA no sooner than 7:30 am Tuesday, as tdw said. So you have Tuesday morning and early afternoon as a "window" for getting that test. Here's what you can get at LAX now, of course things might be different in May.

I hope you get to do the trip, stay healthy, and have fewer hassles in May.

Thanks everyone for the help ....sounds like rapid test in LA early Tuesday morning before flight would work to meet current requirements for Greece. So to be clear... 24 hours before arrival on Wednesday Athens time at 5:30pm would be 5:30pm on Tuesday Athens time.... this would be equivalent to 7:30 am Tuesday here in Los Angeles. Flight here does not leave LAX until 3:00pm which would give us time that morning at airport to test?

I think that math is right, Jeff. Your airline will want your test documentation at LAX check-in. They will also be a good source of updates as May approaches. They want the Greeks to let you in so they don't have to fly you home right away!

Is this a nonstop flight? If not, you may have to think about the rules at connection airports. I'm flying to Ireland via Chicago instead of London so I have to deal with only one country's rules (besides my own).

We are connecting through Frankfurt on the way to Athens....is this a problem?