FBAR exchange rate: which rate to use for foreign accounts
For the FBAR exchange rate, you use the Treasury Reporting Rate of Exchange for December 31 of the reporting year. That single year-end rate is applied to the maximum balance each foreign account reached during the year, even if the peak occurred in March or August. Bank rates, IRS yearly average rates, and rates from the date of the highest balance are not accepted.
This article covers where to find the official Treasury rates, how to convert balances correctly, how the FBAR rate differs from IRS yearly average rates, and what to do if your currency is not listed. The 2025 FBAR is filed in 2026 using the December 31, 2025, rates.
FBAR is filed on FinCEN Form 114 through the BSA E-Filing System, not with your Form 1040.
What exchange rate should you use for FBAR?
The exchange rate for FBAR is the Treasury Reporting Rates of Exchange for the last day of the calendar year being reported.
For the 2025 FBAR filed in 2026, you use the December 31, 2025 Treasury rate for each currency. You do not use the IRS yearly average rate, the spot rate on the date your account peaked, or the rate your foreign bank applied to a particular transaction. FinCEN's rule for reporting the maximum account value is explicit on this point.
The same Treasury year-end rate applies when you file late, file an amended FBAR, or file through a corrective program like the Delinquent FBAR Submission Procedures or Streamlined Filing. The rate is tied to the reporting year, not to when you file.
The mechanics of finding the right balance to convert are covered in our breakdown of the foreign bank account report and our guide to determining the maximum annual account balance for FBAR.
Where to find official FBAR exchange rates
The official source for FBAR exchange rates is the Bureau of the Fiscal Service, which publishes the Treasury Reporting Rates of Exchange quarterly. The December 31 rates are what you need for FBAR.
Treasury rates are expressed as foreign currency units per $1 USD. Most conversions require dividing the foreign currency balance by the Treasury rate, not multiplying. A rate of 21.5 Czech koruna per $1 USD applied to a CZK 215,000 balance gives $10,000, not the other way around.
For the 2025 reporting year, the figures sit in the December 31, 2025, Treasury Reporting Rates of Exchange. The same dataset is searchable through the Treasury currency exchange rates converter.
Example FBAR exchange rate calculation
A US citizen in London held a UK current account that reached £65,000 in July 2025. By December 31, 2025, the balance had dropped to £40,000.
The reportable amount is the July peak, not the year-end balance. The December 31, 2025 Treasury rate for the British pound is applied to £65,000. If Treasury publishes the year-end rate as 0.78 GBP per $1 USD, the calculation is £65,000 ÷ 0.78 = $83,333.33, rounded up to $83,334 on FinCEN Form 114.
Three rules sit inside that one example:
- the highest balance during the year drives the reported amount
- the December 31 Treasury rate is applied regardless of when the peak occurred
- the final USD figure is rounded up to the next whole dollar per FinCEN's rule on reporting the maximum account value
Do you use the year-end balance or the highest balance?
You use the highest balance during the year, converted at the year-end exchange rate. This is the single most common point of confusion in FBAR filing.
FBAR requires the maximum value each account reached at any point during the calendar year, in the account's own currency.
That maximum is then converted to US dollars using the December 31 Treasury rate, regardless of when the peak occurred. An account that hit £80,000 in March 2025 and closed at £10,000 on December 31 is reported at the USD equivalent of £80,000, not £10,000.
The same approach applies whether the account peaked early in the year, late in the year, or only briefly.
FBAR exchange rate vs IRS exchange rate: what's the difference?
The phrase IRS FBAR exchange rates is a misnomer. The IRS does not publish FBAR rates. FBAR rates come from Treasury.
The four rate types you may encounter, and what each one is actually used for:
| Rate type | Source | What it's used for |
|---|---|---|
| Treasury year-end rate | Bureau of the Fiscal Service (December 31) | FBAR (FinCEN Form 114) and Form 8938 |
| IRS yearly average rate | IRS yearly average currency exchange rates | Foreign income reporting on Form 1040 |
| Spot rate | Federal Reserve, central banks, financial data providers | Specific transactions where documentation requires a particular date |
| Bank rate | Your foreign bank's daily rate | Internal use only, not accepted for FBAR |
Treating IRS exchange rates for FBAR as interchangeable with Treasury rates is one of the more common filing errors. The two regimes serve different purposes.
Broader context on what gets reported and where sits in our overview of foreign assets disclosure.
FBAR exchange rate vs Form 8938 exchange rate
FBAR and Form 8938 are separate reporting regimes, and both may apply to the same taxpayer. On rates, the good news is that both use the December 31 Treasury rate. Form 8938 instructions point filers to the same Treasury Reporting Rates of Exchange that FBAR uses.
The differences sit elsewhere:
- filing destination: FBAR is filed with FinCEN through the BSA E-Filing System; Form 8938 is attached to your Form 1040
- thresholds: FBAR has a single $10,000 aggregate threshold; Form 8938 thresholds vary by filing status and whether you live in the US or abroad
- asset scope: FBAR covers foreign financial accounts; Form 8938 covers a broader set of specified foreign financial assets, including some that are not held in an account
When the same asset appears on both forms, the converted USD values should match. If you reported €50,000 on FBAR using the Treasury year-end rate, the same €50,000 should appear on Form 8938 using the same rate. Inconsistent values across the two filings invite IRS questions.
The overlap and divergence are covered in our FBAR vs Form 8938 comparison and our Form 8938 guide.
What if Treasury does not list your currency?
If Treasury does not publish a rate for your currency on December 31, FinCEN permits the use of another verifiable exchange rate. The rule is stated directly in the FinCEN FBAR line item filing instructions: use another verifiable rate and document the source.
In practice, this means:
- using another verifiable exchange rate for December 31 of the reporting year if Treasury does not publish a rate for your currency, and disclosing the rate on Form 8938 if you file that form
- using the rate for December 31 of the reporting year, not an average and not a peak-date rate
- saving documentation of the source, the date, the rate used, and the calculation, kept with your FBAR records for at least 5 years
Countries with multiple exchange rates – for example, official and parallel market rates – present a separate issue. FinCEN's guidance is to use the rate that would apply if the account currency were actually converted to US dollars on the last day of the calendar year.
When a country operates an official rate alongside a parallel rate, the rate that reflects actual convertibility is what FinCEN expects.
How to handle multiple foreign accounts and currencies
Each account is valued separately in its own currency, converted separately at the December 31 Treasury rate for that currency, and then summed in US dollars to test the $10,000 aggregate threshold.
A worked example. A US citizen in Switzerland holds three accounts at the end of 2025:
- Swiss checking account, peak balance CHF 6,000
- German savings account, peak balance EUR 3,500
- USD-denominated foreign brokerage account, peak balance $4,200
Each is converted using the December 31, 2025, Treasury rate for its currency. The USD-denominated foreign account uses its dollar amount directly; no conversion is required. If the three converted USD values sum to more than $10,000 at any point during the year, all three accounts are reported on FBAR – not just the one that pushed the total over.
A few rules that come up often in multi-account filings:
- a USD-denominated account at a foreign bank is still a foreign account for FBAR; report the USD peak balance directly
- a joint account is reported in full by each owner with a financial interest; the value is not divided
- an account closed mid-year is still reported if it held funds during the year
- internal transfers between two of your own foreign accounts do not net out; each account's peak is reported independently, even when the same money moved from one to the other
For couples filing FBARs together, the mechanics of FinCEN Form 114a authorization are covered in our guide to filing FBAR jointly.
Common FBAR exchange rate mistakes
The same handful of errors come up repeatedly in FBAR currency exchange rate conversions.
| Mistake | Why it's wrong | Correct approach |
|---|---|---|
| Using IRS yearly average rates | IRS averages apply to income reporting on Form 1040, not FBAR | Use the December 31 Treasury rate |
| Using the bank's exchange rate | Bank rates are internal and not accepted by FinCEN | Use the Treasury rate; document any alternative if Treasury has no rate |
| Converting the year-end balance instead of the peak | FBAR requires the highest balance during the year | Find the peak balance in account currency, then convert at the December 31 Treasury rate |
| Using the spot rate from the date the account peaked | The rate is tied to December 31, not to the peak date | Apply the December 31 rate regardless of when the peak occurred |
| Dropping smaller accounts after crossing $10,000 | Once aggregate exceeds $10,000, all reportable accounts must be listed | Report every reportable account, regardless of individual size |
| Rounding to the nearest dollar | FinCEN requires rounding up to the next whole dollar | $15,265.25 becomes $15,266, not $15,265 |
| Applying FBAR rules to Form 8938 thresholds | The two regimes have different thresholds | Apply each regime's own threshold; the rate is the same, the threshold rules are not |
The BSA E-Filing System is the filing channel, so review the conversion carefully before submitting.
When is the FBAR due?
The FBAR for the 2025 calendar year is due April 15, 2026, with an automatic extension to October 15, 2026. No extension request is needed.
The extension changes when you file, not which rate you use. The FBAR end-of-year exchange rate for the 2025 reporting year is the December 31, 2025, Treasury rate, whether you file in April, October, or later through a delinquent submission program. The same applies to amended FBARs: the rate is tied to the year being reported.
Cross-filing deadlines across federal returns and FBAR are mapped out in our filing deadlines overview, and extension mechanics sit inside our free expat tax extension service.
What if you used the wrong FBAR exchange rate?
The right correction depends on what the error did to your filing.
If the wrong rate produced a misreported USD value but you still filed timely and reported every account, the issue is generally a value error. An amended FBAR can be filed through the BSA E-Filing System, replacing the original.
If the wrong rate caused you to underreport aggregate values to the point that you mistakenly concluded FBAR was not required – and you didn't file at all – the issue is more serious. Whether the failure was non-willful matters. Two correction paths exist:
- the delinquent FBAR submission procedures, which apply when foreign income was reported on the tax return, FBAR was missed, and no IRS contact has occurred yet
- the Streamlined Filing Procedures, which apply when income reporting was also incomplete and the noncompliance was non-willful
Quiet disclosure – filing late or amended FBARs without using a formal program – carries real risk and is generally not advised.
Quick checklist before filing FBAR
The items below cover the FBAR filing exchange rate mechanics and the broader filing requirements that depend on getting the conversion right.
- all reportable foreign accounts identified, including bank, brokerage, mutual fund, life insurance with cash value, and any account where you have signature authority
- maximum value found for each account in its own currency, using monthly or quarterly statements
- correct December 31 Treasury rate applied for each currency, sourced from Treasury Reporting Rates of Exchange
- alternative rate source documented if Treasury does not list a currency
- aggregate threshold of $10,000 checked across all reportable accounts
- each USD value rounded up to the next whole dollar
- FBAR submitted through the BSA E-Filing System under FinCEN's report of foreign bank and financial accounts requirement
- confirmation page saved and records retained for at least 5 years
FAQs about FBAR exchange rates
The exchange rate for FBAR is the Treasury Reporting Rate of Exchange for December 31 of the reporting year. For the 2025 FBAR filed in 2026, use the December 31, 2025 Treasury rate for each currency.
No. IRS yearly average rates are used for income reporting on Form 1040, not for FBAR. FBAR requires the Treasury year-end rate. Mixing the two is a common filing error.
The highest balance reached at any point during the year, then converted to USD using the December 31 Treasury rate. The peak balance and the conversion rate come from different points in time, which is the rule that confuses most filers.
A USD-denominated account at a foreign institution is still a foreign account for FBAR. No conversion is needed; you report the peak USD balance directly.
Use another verifiable exchange rate for December 31 of the reporting year. Save the source, the rate, and your calculation in your records. If you file Form 8938, disclose the exchange rate used on the form.
Yes. Form 8938 instructions point filers to the same Treasury year-end rate that FBAR uses. The two forms have different thresholds and go to different agencies, but the conversion rate is the same.
No. Bank rates are not accepted for FBAR. FBAR foreign exchange rates must come from the Treasury Reporting Rates of Exchange or, if no Treasury rate is available, another verifiable source documented in your records.
The December 31 rate for the year being reported. A 2022 FBAR filed late in 2026 still uses the December 31, 2022, Treasury rate. The FBAR reporting exchange rate is always tied to the reporting year, not the filing date.
FBAR foreign currency exchange rates are used to convert the maximum value of each foreign financial account into US dollars for reporting on FinCEN Form 114. These rates are based on the Treasury Reporting Rates of Exchange for December 31 of the reporting year.
