Buying and Selling Investments Abroad: US Tax Rules Explained

At some point, most expats end up doing the same thing. You settle into a new country, open a local bank or brokerage account, and think, “I should probably start investing again.”

Buying feels easy enough. A few clicks, maybe some currency conversion, and you’re in.

Then later, usually when you sell something, the questions start. Was that taxable? Which country taxes it? And why do the numbers not quite line up with what you expected?

That gap between “this seems simple” and “this is actually complicated” is where US tax rules tend to sit for expats.

How the US Taxes Investments Abroad

The starting point is straightforward, at least in theory.

The US taxes worldwide income. It doesn’t matter if your brokerage account is in New York, London, or Singapore. If you’re a US citizen, dividends, interest, and capital gains are all potentially taxable.

Where things get less straightforward is when another country is involved. You might pay tax locally on the same income. Sometimes that’s manageable through credits. Sometimes it’s not perfectly aligned.

So the location of the investment doesn’t remove the US from the picture. It just adds another layer.

Buying Investments Abroad: What Actually Happens

Buying an investment, on its own, is not a taxable event. Still, there’s a detail that tends to get overlooked. The purchase price, or cost basis, needs to be tracked in US dollars. Not in euros, not in pounds.

Imagine buying shares of a European company while living in France. You pay in euros, obviously. But from a US tax perspective, that purchase has to be converted into dollars using the exchange rate at the time.

It feels like a small thing. Later, though, it becomes the foundation for calculating your gain or loss.

Holding Investments: Ongoing Tax Considerations

Once you hold the investment, things continue to tick along quietly.

Dividends are usually taxable in the US, even if they’re automatically reinvested. Interest income follows the same idea. You might not see the cash, but it still counts.

And then there are foreign funds. This is where people often pause mid-conversation and say, “Wait, what?”

Certain non-US mutual funds and ETFs can fall under PFIC rules. The tax treatment can be less favorable, and the reporting is… not exactly light. Many expats don’t realize this until after they’ve already invested.

So while holding investments feels passive, the tax side of it isn’t entirely hands-off.

Selling Investments Abroad: Capital Gains and Tax Impact

Selling is where everything becomes visible.

For the 2025 tax year, long-term capital gains tax is still at 0%, 15%, or 20%, depending on your income. Short-term gains are taxed at ordinary income rates. That structure hasn’t changed.

What tends to catch people off guard is how easily gains are triggered.

Rebalancing a portfolio, selling a portion of shares to cover expenses, or shifting between funds can all create taxable events. Even if your intention wasn’t to “take profits,” the IRS may still see it that way.

Then there’s currency. You might sell an investment and feel like you barely made anything in your local currency. But once converted into US dollars, the gain could look larger, or sometimes smaller, depending on exchange rate movements.

For higher-income taxpayers, the 3.8% Net Investment Income Tax may also apply on top of regular capital gains.

Reporting typically runs through Form 8949 and then flows into Schedule D. That part is mechanical, but getting the numbers right is where the effort usually sits.

Special Considerations for Foreign Investments

Foreign investments come with their own personality, if that’s the right way to put it.

PFIC rules are the main issue here. They apply to many foreign mutual funds and ETFs, and the tax treatment can be less favorable than standard capital gains rates. In some cases, gains are taxed at higher rates, with additional calculations layered on top.

This is one of those areas where something that looks like a normal investment locally turns into a more complex situation from a US perspective.

It doesn’t mean you should avoid foreign investments entirely. But it does mean they require a bit more awareness upfront.

Double Taxation and How It’s Managed

A common concern is getting taxed twice.

And, to be fair, that can happen in certain situations. If your country of residence taxes your investment gains and the US does the same, you’re dealing with two systems at once.

The Foreign Tax Credit is designed to help offset that. In many cases, it reduces or eliminates double taxation.

Still, it’s not always perfect. Timing differences or mismatched rules can leave small gaps. Not huge, usually, but noticeable.

Common Mistakes US Expats Make When Investing Abroad

A few patterns tend to repeat.

Forgetting to track cost basis in US dollars.
Ignoring how exchange rates affect gains.
Investing in foreign funds without realizing PFIC rules apply.
Assuming local tax treatment carries over to the US.

None of these are unusual mistakes. They just tend to surface later, when fixing them is harder.

What This Means for Your Investment Strategy

There isn’t a single “correct” way to invest as a US expat.

Some people prioritize simplicity and stick with US-based accounts. Others lean into local options for practical reasons. Most end up somewhere in between.

What matters is understanding the trade-offs before making decisions, not after.

Need Help Managing Investments and US Taxes Abroad?

Sorting through investment decisions is one thing. Layering US tax rules on top of that can make it feel uneven, especially when different countries treat the same income differently.

If you’re unsure how your investments should be reported or structured, getting clarity early can save you from complications later. Expat Tax Online helps Americans abroad handle reporting, compliance, and the details that tend to get missed until they matter most.