The Physical Presence Test, day by day

The Physical Presence Test (PPT) is the simpler of the two ways to qualify for the Foreign Earned Income Exclusion. Unlike Bona Fide Residence, it doesn't care about your intent or your visa status — it only cares about where your body was, day by day.

But "simple" doesn't mean easy. The rule has three traps that trip up most first-time filers: what counts as a "full day," how international airspace is treated, and how to pick the right 12-month window when you didn't spend the full calendar year abroad.

The basic rule

You qualify for FEIE under PPT if, during any consecutive 12-month period, you were physically present in a foreign country (or countries) for at least 330 full days.

Two parts:

• 12-month period: any 365-day window, not necessarily the calendar year. The window must start and end on the same day of the month (e.g., March 18 to March 17 of the following year).
• 330 full days: a "full day" is a 24-hour period beginning at midnight in the foreign country where you are present.

What counts as a foreign day

A day in a foreign country counts as a foreign day if, at any point during that 24-hour midnight-to-midnight window, you were physically present in that foreign country.

Specifically:

• A day you spent entirely in Germany: foreign day.
• A day you flew from Paris to Tokyo (both foreign cities): foreign day for whichever country you were in at midnight.
• A day you crossed the border from France to Switzerland by train: foreign day either way.

What does not count as a foreign day

• Any day you set foot in the United States. Even one hour of a layover at JFK turns the whole 24-hour midnight period into a non-foreign day.
• Any day spent over international waters or airspace. This is the big one. A 10-hour flight from London to Los Angeles: the time in international airspace between leaving UK airspace and entering U.S. airspace is not time in a foreign country. If you cross at midnight in international space, that day is a non-foreign day.
• Time on a U.S. flagged vessel (a U.S.-registered ship or aircraft) in international waters.

How many "U.S. days" can you afford

It's not 35 days. It's 35 days minus your non-foreign days from travel. Since 365 - 330 = 35, you have 35 non-foreign days to spend on any combination of:

• Time physically in the U.S.
• Time over international waters/airspace
• Time on a U.S. flagged vessel

In practice, most expats burn 4–10 non-foreign days per year just on travel between continents. If you plan to take a 3-week trip back to the U.S., model the math first — that 21 days plus your 6 days of travel could put you at 27, leaving you 8 days of margin. One unexpected funeral or work trip and you've blown the test.

The rolling-window trick

This is the most valuable thing in the PPT rules and most expats miss it.

The 12-month window does not have to align with the calendar year. You can choose any 365-day period that gets you to 330 foreign days, and FEIE applies to the portion of your tax year that falls within that window.

Example. You moved from Boston to Berlin on June 1, 2024. By December 31, 2024, you've been in Germany for 7 months — nowhere near 330 days.

Don't despair. Choose a 12-month window of June 1, 2024 to May 31, 2025. As long as during that window you spent 330 foreign days, you qualify under PPT. FEIE then applies to your 2024 earned income earned during the portion of 2024 that falls within the window — i.e., from June 1 through December 31, 2024.

Your 2024 FEIE cap is prorated: 214 days (June 1 – Dec 31) / 365 days × $126,500 ≈ $74,200.

You can do the same trick at the end of your time abroad. Moving back to the U.S. on July 15, 2025? Pick a window of July 16, 2024 to July 15, 2025 — qualifying you for FEIE on 2025 income earned January 1 through July 15.

What "presence in a foreign country" actually means

You must be physically present in a foreign country, on land, with that country's permission. This means:

• Being a tourist or visa-holder: fine.
• Being on a work permit, residence permit, student visa, etc.: fine.
• Being in a country illegally: not fine — the IRS doesn't recognize undocumented presence for PPT.
• Being in a country the U.S. has sanctioned (Iran, Syria, North Korea, Cuba, parts of Ukraine): generally not fine — the IRS lists specific sanctioned countries that don't count.

Antarctica, the deep ocean, and international airspace are not "foreign countries." Cruises and offshore work require careful counting.

How to track your days

A simple spreadsheet beats every app I've seen. Columns:

Date	Country	Foreign day?	Notes
2025-01-01	Germany	Yes	At home in Berlin
2025-01-15	USA	No	Layover JFK, dad's birthday
2025-01-23	International	No	Flight Frankfurt → Tokyo, midnight in airspace

The Form 2555 instructions ask for a list of every trip in and out of the U.S. during your qualifying period, with arrival and departure dates. Keep this contemporaneously — reconstructing it five years later from passport stamps and credit-card receipts is miserable.

Save:

• Boarding passes (or screenshots of them)
• Passport entry/exit stamps
• Hotel bookings and credit-card statements showing the country
• Email signatures with timestamps when you remember to

The IRS will not usually demand this on a quiet 2555 filing, but they will absolutely demand it under audit, and "I think I was probably abroad" will not be enough.

Common PPT mistakes

• Forgetting the airspace day. People plan for 35 U.S. days and then lose a day for each international flight. You need fewer than 35 U.S. days because some of your 35 non-foreign days are flights.
• Counting partial days. "I left LAX at 11:55 PM, so most of the day was foreign." No — the 24-hour midnight period you crossed determines the answer.
• Using the wrong 12-month window. If you spent calendar 2024 abroad except for a 40-day U.S. work trip in October, you fail PPT on a January 1 – December 31 window. But a March 1, 2024 – February 28, 2025 window might give you exactly 330 days. Pick the window that works.
• Ignoring the proration. If your 12-month window covers two tax years, the FEIE cap is prorated for each year — you don't get the full $130,000 for a year you only spent half abroad.
• Cruise ship days. A 10-day cruise that stops in three foreign ports is not 10 foreign days. The time in foreign territorial waters counts; the time at sea between ports usually doesn't.

When to use BFR instead

PPT is brittle. One ill-timed U.S. trip and you lose the whole year. The Bona Fide Residence Test is more flexible — you can spend more time in the U.S. without disqualifying — but it requires you to have lived abroad for an uninterrupted period that includes an entire calendar year with the intent to stay indefinitely.

Most expats use PPT in year one (because they haven't lived abroad for a full calendar year yet) and switch to BFR in year two and beyond. The rolling-window PPT is the bridge year.

Next steps

• The Bona Fide Residence Test
• FEIE in depth
• FEIE vs. Foreign Tax Credit