FEIE 330-day calculator

The 330-day rule, as section 911 writes it

The Foreign Earned Income Exclusion is created by section 911 of the Internal Revenue Code. Section 911(d)(1) defines who qualifies for it: a person whose tax home is in a foreign country and who meets one of two tests. The Physical Presence Test is the second of them, at section 911(d)(1)(B), and it is the mechanical one. A US citizen or resident alien meets it by being present in a foreign country or countries for at least 330 full days during any period of 12 consecutive months. Treasury Regulation section 1.911-2 supplies the detail, and the exclusion itself is claimed on Form 2555, filed with your Form 1040.

Three things have to be true at once:

• A tax home in a foreign country. Your tax home is the general area of your main place of business, employment, or post of duty. Section 911(d)(3) adds the part people miss: you are not treated as having a foreign tax home for any period during which your abode is in the United States. Days abroad on their own do not qualify you.
• 330 full days of foreign presence. They do not have to be consecutive and they do not have to sit inside a calendar year. What they have to be is full days, which is a stricter idea than it sounds.
• One 12-month period. All 330 days must fall inside a single stretch of 12 consecutive months. That stretch can begin on any date, which is why the calculator above lets you slide the window instead of locking it to January.

330 is a floor, not a target. At 329 full days you are not a qualified individual under this test for that window, and the exclusion that depended on it is lost in full rather than reduced. There is no partial credit for coming close.

What counts as a full day

A full day is a continuous 24-hour period that begins at midnight and is spent in a foreign country. That definition does most of the damage, because travel days almost never satisfy it.

• A day split between the United States and somewhere else is not a full foreign day. The day you fly out of the US is normally lost, because part of it was spent in or over US territory.
• Time over international waters is not foreign presence. If you move between two foreign points and the part of the trip outside any country takes less than 24 hours, you are generally treated as being in a foreign country for it. A crossing that keeps you outside every country for 24 hours or more does not get that treatment.
• The IRS applies the same logic on the way out: if you leave the United States and pass over a foreign country before midnight of the day you left, the first day you can count toward the 330 is the day after you left.
• A foreign country means territory under the sovereignty of a government other than the United States, including that country's territorial waters and airspace. US territories and possessions such as Puerto Rico, Guam, the US Virgin Islands, American Samoa, and the Northern Mariana Islands are not foreign countries for this test. Neither is Antarctica.
• Why you were abroad is irrelevant. Work, holiday, family, or nothing at all, a full day in a foreign country counts the same, provided the tax home requirement holds for the period.

The calculator above charges you every calendar day from the day you arrive in the US to the day you leave, which is the right treatment for the US leg. It cannot see your flight times, so it does not know whether the day you landed back abroad was a full day. Read its buffer figure as the optimistic one and keep slack.

A worked example

Maria is a US citizen working in Lisbon. She tests the window 1 March 2025 to 28 February 2026, which is 365 days long. She needs 330 full foreign days, so she can spend 35 days in the United States inside that window and not one more. She made three trips home.

365 days in the window, minus 31 US days, leaves 334 foreign days. That clears 330 with four days to spare, so on a plain reading Maria is a qualified individual for this window.

Now apply the travel-day rule

All three return flights left the US in the evening and crossed the Atlantic overnight. On each of those arrival days Maria was over international waters at midnight and for hours afterwards, so none of them is a full day in a foreign country. Three more days come off the count. Her real figure is 331, not 334.

She still qualifies, but her margin went from four days to one. This is the pattern that catches people out. The arithmetic of whole days is the easy part, and the days at the edges of each trip are where the count is actually lost. Travel days only ever cost you days, they never hand any back.

When the 12-month window straddles two tax years

The 12-month period is not the tax year, and the two rarely line up. Say you moved abroad on 15 March 2025 and stayed. You cannot reach 330 foreign days inside calendar 2025, and you do not need to: test the window 16 March 2025 to 15 March 2026 instead, and the Physical Presence Test is met on that window.

What changes is how much you can exclude. Section 911(b)(2) computes the ceiling on a daily basis at an annual rate, so a partial year of qualification gets a partial ceiling. On the window above, 291 qualifying days fall inside the 2025 tax year (16 March to 31 December). Your 2025 ceiling is therefore 291/365 of the annual maximum, which is 79.7 percent of it. The rest of the window supports your 2026 return on the same pro-rata basis.

The annual maximum is indexed for inflation, so take the figure for your tax year from the Form 2555 instructions rather than from memory or from an article. Section 911 also provides a foreign housing exclusion or deduction that runs off the same qualification, with a base amount and a location-specific ceiling published alongside that form.

Timing matters as well. If your 12-month window has not closed by the filing deadline, you are not stuck guessing: Form 2350 exists so that US taxpayers abroad can extend the return until they have qualified.

The Physical Presence Test is not the Substantial Presence Test

These two are confused constantly, and they point in opposite directions. The Physical Presence Test, the one on this page, counts days spent outside the United States. It applies to US citizens and resident aliens, who already owe US tax on worldwide income, and passing it is good news, because it unlocks an exclusion.

The Substantial Presence Test counts days spent inside the United States. It applies to people who are neither US citizens nor green-card holders, it uses a weighted three-year formula rather than a single count, and passing it is usually unwelcome, because it makes you a US tax resident taxable on worldwide income.

If the test you actually need is the one that decides US residency for a visa holder, use the Substantial Presence Test calculator instead. The tell is the direction of travel: 330 days abroad qualifies you for an exclusion, and 183 weighted days in the US makes you a resident.

Physical presence or bona fide residence

Section 911(d)(1)(A) offers the other route to the same exclusion: being a bona fide resident of a foreign country for an uninterrupted period that includes an entire tax year. The two tests suit different situations.

• Physical presence is mechanical. You count days, and you either clear 330 or you do not. No judgement is involved, which cuts both ways: there is nothing to argue about and nothing to forgive.
• Bona fide residence is a facts-and-circumstances test. It weighs your intent, the nature and length of the stay, whether you have established a home and a life in the country, and how you have presented yourself to the local authorities. It requires an uninterrupted period covering a full tax year, so it is not available for your first partial year abroad, but once established it survives ordinary trips home that would destroy a 330-day count.
• Telling the foreign country you are not resident can close that door. If you have filed a statement of non-residence with the local authorities and they have held you not subject to their income tax on those earnings, you are generally not a bona fide resident of that country for section 911 purposes.
• Resident aliens have limited access to it. The bona fide residence route is generally open to US citizens, and to US resident aliens only where a tax treaty non-discrimination provision extends it to them. The Physical Presence Test carries no such restriction.

Plenty of long-term expats satisfy both in a settled year and fall back on physical presence only in the year they arrive and the year they leave. If you are weighing the two, run the day count first, because it is the one that can be answered with certainty.

Where the 330-day count goes wrong

These are the failures that recur, and almost all of them are counting failures rather than legal ones.

1. Treating the 12-month period as a calendar year. Nothing in the test ties the window to January. If a January to December count fails, slide the window and test again before concluding the year is lost.
2. Counting nights instead of days. A trip home from a Friday to the Sunday nine days later is eleven days charged, not nine nights. Both travel days are in, and the day you land back abroad may be in as well.
3. Assuming a US territory is foreign. A week in Puerto Rico or the US Virgin Islands is US presence for this test even though neither is a US state. It is a common way to lose days you thought you had banked.
4. Treating time at sea as neutral. Time outside every country's territory is not foreign presence. A repositioning cruise, or any crossing that keeps you outside any country for 24 hours or more, can cost days the calendar makes look free.
5. Ignoring the tax home requirement. 330 days abroad does nothing for you if your abode remained in the United States. This is where people with a US family home, a US base, and a lot of travel most often fail, and it is a separate hurdle from the day count.
6. Expecting the exclusion to cover everything. It covers foreign earned income: wages, salaries, professional fees, and self-employment income for services performed abroad. It does not cover interest, dividends, capital gains, rents, pensions, or annuities. It does not reduce self-employment tax, and it does not move your remaining income into lower brackets, because tax on the income you did not exclude is figured at the rates that would have applied without the exclusion.
7. Claiming a foreign tax credit on excluded income. The statute denies the double benefit. Foreign taxes allocable to income you excluded cannot also be taken as a credit or a deduction, which is why the exclusion is not automatically the better answer for someone living in a high-tax country.
8. Forgetting the emergency waiver. Section 911(d)(4) waives the minimum time requirement where you had to leave a country because of war, civil unrest, or similar adverse conditions, and the IRS publishes the countries and dates it applies to each year. If you were evacuated, check that list before writing the window off.
9. Assuming the exclusion is automatic. It is an election, claimed on Form 2555 with a filed return. You still file even if the exclusion covers everything you earned. And once you revoke the election, you generally cannot elect again for five tax years without IRS consent.
10. Keeping no record. The burden of proof is yours. Boarding passes, passport stamps, and a contemporaneous day-by-day log are what a 330-day claim is actually made of.

For how the 330-day window interacts with every other rule an expat faces at the same time, read the expat day-counter guide. For the other route to the same exclusion, see the bona fide residence test in the glossary.