What Counts as the United States for Day Counting Purposes

What Counts as the United States for Day Counting Purposes

For the presence test under IRC section 937, the United States means only the 50 states and the District of Columbia. Puerto Rico isn't part of it. Neither is any foreign country. That one sentence decides how every day of your year gets sorted, and it's the foundation the 183 day threshold, the 90 day alternative, and the 30 day allowance are all built on top of.

Here's why it matters: the presence test doesn't ask how many days you spent "away." It asks how many days you spent in the United States, specifically, using a definition of that term that's narrower than most people assume.

What Does "United States" Actually Mean?

The statutory chain

The definition traces back to 26 U.S.C. 7701(a)(9): "the term United States when used in a geographical sense includes only the States and the District of Columbia." That's the whole definition. Fifty states, plus DC. Nothing else.

The presence test regulation doesn't restate this. Instead, 26 CFR 1.937-1(a)(2)(ii) imports it directly: "United States, when used in a geographical sense, is defined in section 7701(a)(9)." Every rule that follows in the regulation, the day of presence standard, the carve-outs, the possession side of the ledger, leans on this same imported definition.

What this excludes

Puerto Rico, Guam, American Samoa, the Northern Mariana Islands, and the US Virgin Islands are all US territory in the everyday sense of that phrase. None of them are "the United States" for this rule. Write that one down: US territory and United States are not the same thing here, and a day spent in Puerto Rico is a possession day, not a US day.

What Counts as a Day in the United States?

The basic standard

Under 26 CFR 1.937-1(c)(3)(ii), you're considered present in the United States on any day you're physically present there at any time during that day. Simple physical presence, not a residence test, not an intent test.

The mirror rule sits on the other side. Under 1.937-1(c)(3)(i), you're counted as present in Puerto Rico on any day you're physically present there, or absent for qualifying medical treatment or a declared major disaster. See what counts as a day in Puerto Rico for the full possession-side mechanics.

The carve-outs

A short, closed list of days doesn't count toward US presence even though you were physically there:

• Days present to receive qualifying medical treatment, for yourself or while accompanying a family member receiving it
• Days in transit between two points outside the United States, when the time in the US is under 24 hours, see the under 24 hour transit rule
• Days as a student, as defined under section 152(f)(2)
• Days competing as a professional athlete in a charitable sports event
• Days serving as an elected official of the relevant possession

Every other day physically spent in one of the 50 states or DC counts as a US day. No exceptions beyond that list.

Why the Definition Matters: The 90 Day Alternative

One path to satisfying the presence test is being present in the United States for no more than 90 days during the tax year, per IRS Publication 570. That count only works if the underlying sort was done correctly first. A day actually spent in Puerto Rico, or in a foreign country, isn't a US day and doesn't count toward the 90. Misclassify a single day in either direction and the total shifts, and the total is exactly what the test checks against. See the 90 day presence test for the full mechanics of that alternative.

Why the Definition Matters: Foreign Country Days

A day spent in a foreign country isn't a US day. It falls outside the section 7701(a)(9) definition for the same reason Puerto Rico does: it's not one of the 50 states or DC. But a foreign day also isn't automatically a possession day, since you weren't physically in Puerto Rico either.

Publication 570 addresses that gap with an allowance. Up to 30 days spent outside both the relevant possession and the United States, for business or personal travel, can still count as territory presence, provided your territory presence days otherwise exceed your US presence days for the year. See the 30 day rule for the full allowance mechanics. That allowance sits directly on top of the definition in this article: you can't apply it correctly without first knowing that a day in Madrid is neither a US day nor, by default, a Puerto Rico day.

An automatic day ledger that sorts every day into US, Puerto Rico, or foreign as it happens, rather than asking you to reconstruct the classification at filing time, is exactly what One83 keeps for you.

How This Fits Into the Presence Test

26 U.S.C. 937(a) sets the 183 day possession presence threshold and requires a closer connection to Puerto Rico than to the United States or any foreign country. The statute itself, though, doesn't define "United States." That definition lives in a different code section entirely, imported into the presence test regulation by cross-reference.

The pieces stack in one direction. The definition in section 7701(a)(9) is the foundation, the day of presence standard in 1.937-1 applies it, and the 183 day, 90 day, and 30 day rules all depend on getting that foundation right before anything else gets calculated.

Frequently Asked Questions

Does Puerto Rico count as the United States for the presence test?

No. For purposes of IRC section 937 and the presence test, the United States means only the 50 states and the District of Columbia, as defined in 26 U.S.C. 7701(a)(9). Puerto Rico is a US territory in the ordinary sense, but it's not part of the United States as that term is defined for this rule. A day spent in Puerto Rico is a possession day, not a US day.

Is a day in a foreign country the same as a day in the United States?

No. A day spent in a foreign country isn't a US day, because a foreign country falls outside the 50 states and DC definition just as Puerto Rico does. It's also not automatically a possession day. Publication 570 allows up to 30 such days to still count as territory presence in a given year, provided territory presence days otherwise exceed US presence days.

What is a US day for the presence test?

You're considered present in the United States on any day you're physically present there at any point during that day, per 26 CFR 1.937-1(c)(3)(ii). A short list of carve-outs doesn't count toward US presence: qualifying medical treatment days, transit under 24 hours between two points outside the US, days as a student, days as a professional athlete at a charitable sports event, and days serving as an elected official of the possession.

Where does the 50 states and DC definition come from?

It traces back to 26 U.S.C. 7701(a)(9), the Internal Revenue Code's general geographical definition of United States. The presence test regulation, 26 CFR 1.937-1(a)(2)(ii), imports that definition by cross-reference rather than restating it, so the same definition governs every IRC provision that uses the term, including the Puerto Rico bona fide residency rules.

Why does this definition matter if I'm just counting days?

Because two of the paths that make up the presence test, the 183 day possession threshold and the 90 day US presence alternative, both depend on correctly sorting every day of your year into US, possession, or foreign. Get the definition wrong and a day you counted as Puerto Rico presence, or excluded as a US day, may not hold up under review.

Conclusion

The United States, for day counting purposes, means the 50 states and the District of Columbia and nothing more. Puerto Rico isn't the United States under this definition, and neither is any foreign country. Every other rule in this domain, the 183 day threshold, the 90 day alternative, the 30 day allowance, depends on sorting each day correctly against that one flat sentence first. For the possession-side counterpart of this same mechanic, see what counts as a day in Puerto Rico.

One83 is a tracking tool, not tax advice. Consult a licensed tax professional about your situation.