The short answer
For each foreign account on your FBAR, the maximum account value is a reasonable approximation of the greatest value of currency or other assets in the account at any point during the calendar year. It is not simply the year-end balance. You convert it to U.S. dollars using the Treasury exchange rate for the last day of the calendar year, and record it in whole dollars, rounded up.
This guide assumes you already know an FBAR is required. If you are still deciding, start with How the $10,000 rule really works.
Step by step
- Find the highest value in the account's own currency. Periodic statements (for example, monthly) may be relied on if they fairly reflect the maximum value during the year.
- Convert to U.S. dollars at the Treasury Reporting Rate of Exchange for the last day of the calendar year — for 2025, the rate as of December 31, 2025. If no Treasury rate is available for the currency, use another verifiable exchange rate and provide the source.
- Round up to the next whole dollar. FinCEN's example: $15,265.25 is recorded as $15,266.
- If the value is negative, enter zero.
Why the December 31 balance is often wrong
Many people look only at their year-end statement. But if you moved money out during the year — for example, you wired savings to the U.S. in June and the account was nearly empty by December — the maximum value is the June peak, not the December balance.
When statements don't tell the whole story
Periodic statements are acceptable only if they fairly reflect the maximum value. They may not, for example, when a large deposit arrived and left between two statement dates. When the statements do not fairly reflect the maximum value, the requirement is still a reasonable approximation of the greatest value in the account during the year. FinCEN's guidance does not prescribe a particular method for that. As a practical step (not an official rule), keep whatever records you relied on.
Example: several accounts with peaks on different dates
Kai, a U.S. resident, has three accounts in Taiwan during 2025. Each account's highest balance came on a different date. Using an illustrative year-end rate of NT$1 = US$0.031 (not an actual published rate):
| Account | Highest balance (NT$) | Date of peak | Maximum value (US$, rounded up) |
|---|---|---|---|
| Checking, Bank A | NT$180,000 | March 2025 | $5,580 |
| Savings, Bank B | NT$210,000 | August 2025 | $6,510 |
| Time deposit, Bank B | NT$300,000 | All year | $9,300 |
| Aggregate of maximum values | $21,390 |
Two separate questions come out of this table:
- Filing threshold: the aggregate of the maximum values ($21,390) is more than $10,000, so an FBAR is required — even though the three peaks happened at different times and the accounts never held $21,390 on the same day.
- What Kai reports: each account's own maximum value ($5,580, $6,510, and $9,300), not the aggregate.
For the FBAR, the conversion uses the rate for the last day of the calendar year, even if the account peaked in March. Use the same Treasury rate table for every account in the same currency.
Records to keep
For each reported account, keep the name on the account, the account number, the name and address of the foreign bank, the type of account, and the maximum value during the year — generally for five years from the FBAR due date. As a practical step, also keep the statements or other records you used and note the exchange rate source.
Form 8938 is valued separately
Form 8938 also asks for maximum values, but it has its own thresholds and instructions. Don't assume your FBAR numbers automatically answer the Form 8938 question. See FBAR vs. Form 8938.