The impact of currency fluctuations on your US taxes

Josh Katz, CPA
Author: Josh Katz, CPA
Updated: October 22, 2025

For Americans living abroad, managing finances often involves dealing with foreign currencies. From paying bills to earning income, currency fluctuations can have a significant effect on your financial situation. But beyond everyday expenses, these fluctuations can also impact your US tax obligations. Understanding how currency changes can influence your tax filings is essential for avoiding surprises when it comes time to file your US tax return.

Here’s a closer look at how currency fluctuations might affect your US taxes and what you can do to manage these impacts.


Foreign Income Reporting

For US citizens, all income, regardless of where it is earned, is subject to US taxation. However, if you’re earning income in a foreign currency, you’ll need to report it in US dollars. This is where currency fluctuations come into play.

When you receive foreign income, whether through wages, business income, or dividends, the amount must be converted into US dollars using an appropriate exchange rate. The Internal Revenue Service (IRS) generally requires taxpayers to use the exchange rate in effect on the day the income is received. For monthly or periodic income, the IRS allows using an average exchange rate for the period, such as for the year.

Example: If you earned €50,000 in 2023 while living in Germany, and the exchange rate on the date you received the payment was 1 EUR = 1.05 USD, you would report your income as $52,500 USD (50,000 EUR * 1.05). However, if the exchange rate changes later in the year, the value of your income in US dollars will change as well. This could have an effect on the total income you report, which in turn impacts your overall tax liability.


Foreign Earned Income Exclusion (FEIE)

Many American expats rely on the Foreign Earned Income Exclusion (FEIE) to exclude a portion of their foreign-earned income from US taxation. For the 2023 tax year, the exclusion amount is up to $120,000 per qualifying individual. However, this exclusion is also affected by currency fluctuations.

When calculating the amount of foreign-earned income you wish to exclude, you must convert your income into US dollars at the correct exchange rate for the year. If the value of the foreign currency decreases relative to the US dollar, your exclusion amount might be lower when reported in dollars. Conversely, if the foreign currency appreciates, your exclusion could be higher.

Example: If you earned €100,000 and the exchange rate was 1 EUR = 1.05 USD at the start of the year, your exclusion would be $105,000. However, if the exchange rate shifts to 1 EUR = 1.10 USD by the end of the year, your exclusion could rise to $110,000.

This underscores the importance of monitoring currency trends and accurately calculating your exclusion amount each year.


Foreign Tax Credit

In addition to the FEIE, another tax benefit available to American expats is the Foreign Tax Credit (FTC). The FTC allows you to offset US tax liability by the amount of foreign taxes you paid on your foreign income. As with the FEIE, currency fluctuations can impact the amount of the credit you claim.

When reporting foreign taxes paid, you must convert the foreign currency into US dollars at the exchange rate in effect on the date the tax payment was made. Fluctuating exchange rates can result in discrepancies between the amount of foreign taxes paid and the amount that is converted for US tax purposes, potentially affecting your ability to claim the full credit.

Example: If you paid €10,000 in foreign taxes, but the exchange rate at the time of payment was 1 EUR = 1.08 USD, the US dollar equivalent of your foreign taxes would be $10,800. If the exchange rate changes later in the year, the conversion could be different, potentially altering the amount of credit you are eligible to claim.


Foreign Investments and Capital Gains

Another area where currency fluctuations can impact your US taxes is in the reporting of foreign investments, such as stocks, bonds, and real estate. When you sell an investment in a foreign currency, the proceeds must be converted to US dollars for tax reporting. If the foreign currency has fluctuated in value since the time of purchase, it can affect your capital gains calculation.

Example: If you purchased shares in a foreign company for €10,000 and sold them for €12,000, you would have a capital gain of €2,000. However, if the exchange rate changed from 1 EUR = 1.10 USD at the time of purchase to 1 EUR = 1.05 USD at the time of sale, the U.S. dollar equivalent of your capital gain would be different.

When filing taxes, the IRS requires that you calculate your capital gains or losses in US dollars, meaning fluctuations in currency value between the time of purchase and the time of sale can affect your reported gain or loss.

 


Reporting Requirements

The IRS has specific reporting requirements for Americans with foreign assets. If you have foreign bank accounts or other financial accounts worth more than $10,000 in aggregate at any point during the year, you are required to file FBAR (Foreign Bank Account Report) and, in some cases, Form 8938 (Statement of Specified Foreign Financial Assets).

Currency fluctuations can influence the total value of these accounts in US dollar terms. Even if the balance of your foreign account doesn’t change in the foreign currency, fluctuations in the exchange rate can impact the total value reported on your FBAR or Form 8938.


How to protect yourself from currency fluctuation?

While you can’t control currency fluctuations, there are strategies you can use to minimize their impact on your taxes:

Track exchange rates regularly: Monitor exchange rates throughout the year, especially if you’re dealing with significant amounts of foreign income or investments. This will help you stay informed and ensure that you’re using the correct rates when reporting your income and taxes.

Consult a tax professional: Working with a tax professional who is experienced in expat tax issues can help you navigate the complexities of currency conversions, especially when dealing with fluctuating exchange rates.

Plan for potential adjustments: Currency fluctuations can sometimes result in unexpected tax liabilities or benefits. Setting aside funds to account for these adjustments can help you avoid surprises when it’s time to file your tax return.

Currency fluctuations are an important factor to consider when filing US taxes as an American living abroad. From income reporting to claiming tax credits and exclusions, these fluctuations can have a direct impact on your tax liability. To ensure you comply with US tax laws and make the most of available benefits, it’s crucial to stay on top of exchange rates and consult with a tax professional who understands the nuances of expat taxes.