Tax Treatment of Unrealized FX Gains and Losses

Unrealized foreign currency gains and losses are generally not taxable at the federal level, and that is the short answer on the tax treatment of unrealized FX gains and losses. The U.S. system waits for a realization event before a currency swing becomes income or a deductible loss, so paper movements in the dollar value of your foreign-currency holdings do not appear on your return. The one meaningful exception involves certain regulated futures and interbank foreign currency contracts under Section 1256 of the Internal Revenue Code, which are marked to market at year-end and taxed as if you had sold them on December 31.

What Counts as a Realization Event

A realization event is the moment your economic position becomes final. Exchanging one currency for another at a bank or currency exchange is the clearest trigger. Using foreign-currency funds to buy something, receiving payment on a foreign-denominated receivable, or paying off a debt denominated in a foreign currency all count too, because each one locks in a specific dollar value that can be compared to your original cost. Until one of these events occurs, any gain or loss is theoretical and could reverse the next day.

This matters for day-to-day record keeping. If you hold euros in a foreign bank account and the euro strengthens against the dollar, your statement may show a higher dollar-equivalent balance. That increase is not income yet. You owe nothing until you convert those euros back to dollars or spend them. The rule avoids taxing every minor market fluctuation and waits until real economic value has been captured or lost.

When Unrealized Gains Do Get Taxed: Section 1256 Contracts

Section 1256 creates the main departure from the wait-for-realization rule. If you hold a Section 1256 contract at the end of the tax year, the IRS treats it as if you sold it at fair market value on the last business day of the year. The resulting gain or loss goes on that year’s return even though you still hold the position.¹

Section 1256 contracts include regulated futures contracts, foreign currency contracts traded in the interbank market, and nonequity options.¹ A foreign currency contract under this section must require delivery of (or settlement based on) a foreign currency that is also traded through regulated futures contracts, must be traded in the interbank market, and must be entered into at arm’s length at an interbank price.² Retail spot forex accounts typically do not qualify unless the broker routes trades through the interbank market.

The tax treatment on qualifying contracts uses a 60/40 split: 60% of the gain or loss is long-term capital gain or loss and 40% is short-term.¹ With a top long-term rate of 20% and a top short-term rate of 37%, the blended top rate works out to roughly 26.8%.³ Section 1256 gains and losses are reported on Form 6781, with the 40% short-term portion flowing to Schedule D, Line 4, and the 60% long-term portion to Schedule D, Line 11.⁴

How Gains Are Taxed Once You Realize Them

Outside the Section 1256 exception, tax only enters the picture after a realization event, and most realized foreign currency gains and losses fall under Section 988. The default rule is that currency gains and losses are ordinary income or ordinary loss.⁵ That puts them at the same progressive rates as wages, ranging from 10% to 37% for the 2026 tax year.⁶

Section 988 transactions include acquiring or disposing of nonfunctional currency, holding debt instruments denominated in a foreign currency, accruing foreign-currency expenses or receipts, and entering into forward contracts, futures, or options tied to a foreign currency’s value.⁷ In everyday terms, that covers invoicing a customer in yen or paying a supplier in euros. The difference between the dollar value when you booked the transaction and the dollar value when you actually collected or paid becomes an ordinary gain or loss.

Ordinary treatment carries a real upside on the loss side. Capital losses are capped at $3,000 in net annual deduction against ordinary income, but Section 988 ordinary losses can offset your other ordinary income dollar for dollar with no annual cap.⁵

The Personal Transaction Exception

Individuals converting leftover foreign currency from a vacation or personal purchase get special treatment. Section 988(e) excludes personal foreign currency transactions from the ordinary-income rules, and any gain of $200 or less from a personal exchange is not recognized at all.⁵ Bring home £500 from a London trip and convert it later at a slightly better rate, and the small profit is tax-free as long as it stays at or below $200.

If the gain exceeds $200, the entire amount is taxable as a capital gain rather than ordinary income. A loss on a personal currency conversion is never deductible, the same way a loss on selling personal-use property is not deductible. A personal transaction for these purposes is any transaction not connected to a trade or business or an investment activity.⁵

Electing Capital Gain Treatment

Taxpayers who trade foreign currency through forward contracts, futures, or options can elect out of Section 988’s ordinary-income default and treat their gains and losses as capital instead. The election is available only when the contract is a capital asset in your hands and is not part of a straddle.⁵

The timing is strict. You must identify the transaction and make the election before the close of the day you enter into it, and documenting the choice in your own records at that time is what supports it if the IRS asks. Consistent winners sometimes prefer capital treatment for access to lower long-term rates; those who tend to generate losses often stick with the default to keep the unlimited loss offset. The choice is irrevocable for each transaction.

Calculating the Gain or Loss

Every taxpayer has a functional currency that serves as the baseline for measuring gains and losses. For most U.S. individuals, that is the dollar. A qualified business unit that conducts a significant portion of its activities in a foreign currency and keeps its books in that currency may use the foreign currency instead. If the unit’s activities are primarily conducted in dollars, though, the dollar remains the functional currency regardless of where the business sits.⁸

You need two exchange rates to calculate the gain or loss: the rate on the date you acquired the foreign currency (your basis) and the rate on the date of the realization event, or the year-end mark-to-market date for a Section 1256 contract. The IRS does not mandate a single official exchange rate source and accepts any posted rate as long as you use it consistently.⁹¹⁰¹¹ For transactions spread throughout the year, the IRS generally expects the spot rate on the date of each transaction rather than a yearly average.

The math itself is straightforward. If you bought €10,000 when the rate was $1.08 per euro (basis of $10,800) and later converted back at $1.12 per euro (proceeds of $11,200), your gain is $400. Keep detailed logs of acquisition dates, conversion dates, and the exchange rates used for each event. For brokerage accounts, Form 1099-B may report proceeds and cost basis for certain trades.¹²

Where It Goes on Your Return

The reporting line depends on which rule governs the gain or loss.

Section 988 ordinary gains and losses go on Schedule 1 (Form 1040), Line 8z, as other income, labeled with the type and amount. Sole proprietors who incur currency gains and losses through business operations report them on Schedule C instead.¹³
Capital gains from a Section 988 election go on Form 8949 with totals flowing to Schedule D.¹⁴
Section 1256 contracts go on Form 6781, which handles the 60/40 split described above.⁴
Personal transactions with a gain above $200 go on Form 8949 and Schedule D. Gains of $200 or less need not be reported.

Foreign Account Disclosures Apply Even Without a Gain

The lack of a taxable gain does not remove separate reporting obligations for holding currency abroad. If the combined value of all your foreign financial accounts exceeds $10,000 at any point during the year, you must file FinCEN Form 114, the FBAR, by April 15 with an automatic extension to October 15.¹⁵ Under the Foreign Account Tax Compliance Act, you may also owe Form 8938 with your tax return. For a single taxpayer living in the United States, filing is required if specified foreign financial assets exceed $50,000 on the last day of the year or $75,000 at any time during the year; married couples filing jointly have thresholds of $100,000 and $150,000. Taxpayers living abroad face significantly higher thresholds.

The two filings overlap but are not interchangeable, and you may owe both. FBAR penalties reach up to $10,000 per non-willful violation, adjusted for inflation, and up to 50% of the account balance for willful violations. Those penalties apply even when you owe no tax on the underlying currency, so the disclosure question is worth checking every year you hold foreign accounts, regardless of whether the currency has moved.

1
Office of the Law Revision Counsel. 26 USC 1256 – Section 1256 Contracts Marked to Market
2
Federal Register. Definition of Foreign Currency Contract Under Section 1256
3
Internal Revenue Service. Topic No. 409, Capital Gains and Losses
4
Internal Revenue Service. Form 6781 – Gains and Losses From Section 1256 Contracts and Straddles
5
Office of the Law Revision Counsel. 26 USC 988 – Treatment of Certain Foreign Currency Transactions
6
Internal Revenue Service. Federal Income Tax Rates and Brackets
7
Internal Revenue Service. Overview of IRC Section 988 Nonfunctional Currency Transactions
8
Office of the Law Revision Counsel. 26 USC 985 – Functional Currency
9
Internal Revenue Service. Yearly Average Currency Exchange Rates
10
Federal Reserve Board. Foreign Exchange Rates – H.10
11
U.S. Treasury Fiscal Data. Treasury Reporting Rates of Exchange
12
Internal Revenue Service. About Form 1099-B, Proceeds From Broker and Barter Exchange Transactions
13
Internal Revenue Service. Schedule 1 (Form 1040)
14
Internal Revenue Service. About Form 8949, Sales and Other Dispositions of Capital Assets
15
FinCEN.gov. Report Foreign Bank and Financial Accounts