IRS Foreign Bank Account Interest Currency Conversion Calculator — Free Tool (2026)
Free Currency Conversion Calculator for IRS Reporting
Enter your foreign interest income below. The calculator will convert it to USD using the correct official Treasury rate and show you exactly where to report it on your tax forms.
Quick Reference: Sample Conversions for IRS Reporting
Use this table to quickly see how different foreign currency amounts convert to USD using the official yearly average exchange rate for interest income (IRS Publication 17). These examples are pre-calculated for the 2025 tax year using rates from FiscalData.Treasury.gov. For FBAR filings, remember to round up to the nearest whole dollar.
| Currency | Code | Amount | Exchange Rate (Yearly Avg) | USD Equivalent | FBAR (Rounded Up) |
|---|---|---|---|---|---|
| 🇪🇺 Euro | EUR | €1,000.00 | 1.12 | $892.86 | $893 |
| 🇪🇺 Euro | EUR | €5,000.00 | 1.12 | $4,464.29 | $4,465 |
| 🇪🇺 Euro | EUR | €10,000.00 | 1.12 | $8,928.57 | $8,929 |
| 🇬🇧 British Pound | GBP | £1,000.00 | 1.28 | $781.25 | $782 |
| 🇬🇧 British Pound | GBP | £5,000.00 | 1.28 | $3,906.25 | $3,907 |
| 🇬🇧 British Pound | GBP | £10,000.00 | 1.28 | $7,812.50 | $7,813 |
| 🇯🇵 Japanese Yen | JPY | ¥100,000 | 149.00 | $671.14 | $672 |
| 🇯🇵 Japanese Yen | JPY | ¥500,000 | 149.00 | $3,355.70 | $3,356 |
| 🇯🇵 Japanese Yen | JPY | ¥1,000,000 | 149.00 | $6,711.41 | $6,712 |
| 🇨🇦 Canadian Dollar | CAD | C$1,000.00 | 0.73 | $1,369.86 | $1,370 |
| 🇨🇦 Canadian Dollar | CAD | C$5,000.00 | 0.73 | $6,849.32 | $6,850 |
| 🇨🇦 Canadian Dollar | CAD | C$10,000.00 | 0.73 | $13,698.63 | $13,699 |
| 🇮🇳 Indian Rupee | INR | ₹10,000 | 83.00 | $120.48 | $121 |
| 🇮🇳 Indian Rupee | INR | ₹50,000 | 83.00 | $602.41 | $603 |
| 🇮🇳 Indian Rupee | INR | ₹100,000 | 83.00 | $1,204.82 | $1,205 |
| 🇲🇽 Mexican Peso | MXN | Mex$1,000 | 18.50 | $54.05 | $55 |
| 🇲🇽 Mexican Peso | MXN | Mex$5,000 | 18.50 | $270.27 | $271 |
| 🇲🇽 Mexican Peso | MXN | Mex$10,000 | 18.50 | $540.54 | $541 |
| 🇨🇭 Swiss Franc | CHF | Fr 1,000.00 | 1.08 | $925.93 | $926 |
| 🇨🇭 Swiss Franc | CHF | Fr 5,000.00 | 1.08 | $4,629.63 | $4,630 |
| 🇨🇭 Swiss Franc | CHF | Fr 10,000.00 | 1.08 | $9,259.26 | $9,260 |
| 🇦🇺 Australian Dollar | AUD | A$1,000.00 | 0.65 | $1,538.46 | $1,539 |
| 🇦🇺 Australian Dollar | AUD | A$5,000.00 | 0.65 | $7,692.31 | $7,693 |
| 🇦🇺 Australian Dollar | AUD | A$10,000.00 | 0.65 | $15,384.62 | $15,385 |
Which Exchange Rate Should You Use?
The answer depends on what you are reporting. The IRS and FinCEN require different rates for different purposes. Use this guide to select the correct rate for your situation.
| What You Are Reporting | Which Rate to Use | Source | Example Rate (2025) |
|---|---|---|---|
| Form 1040 Schedule B Interest income (recurring) | Yearly Average | IRS Publication 17 | EUR: 1.12 |
| FBAR (FinCEN Form 114) Maximum account value | FinCEN Instructions | EUR: 1.10 | |
| Form 8938 (FATCA) Specified foreign assets | December 31 Treasury | Form 8938 Instructions | EUR: 1.10 |
| One-time transaction Single payment or conversion | Spot Rate | IRS Publication 17 | Rate on transaction date |
Key takeaway: For most taxpayers with foreign interest income, the yearly average exchange rate is the correct rate for Form 1040 Schedule B. The December 31 Treasury rate is used for FBAR and Form 8938.
Why the Yearly Average Rate for Interest Income?
Interest income is earned gradually throughout the year. The yearly average exchange rate smooths out daily fluctuations and provides a consistent conversion method for recurring income. This aligns with the IRS guidance in Publication 17, which states that taxpayers should use a reasonable exchange rate for converting foreign currency income.
The yearly average rate is calculated by the U.S. Department of the Treasury using daily exchange rates from the Federal Reserve. The Treasury publishes these rates annually through FiscalData.Treasury.gov.
When to Use the Spot Rate
The spot rate applies to specific one-time transactions, such as a single interest payment received on a specific date, a foreign currency conversion, or a one-time distribution. For these situations, use the exchange rate on the date the transaction occurred.
For recurring interest income, the yearly average rate is preferred. The IRS considers the yearly average rate a reasonable method for converting recurring income streams.
FBAR (FinCEN Form 114) Conversion Rules
The FBAR, or FinCEN Form 114, requires U.S. persons to report foreign financial accounts with an aggregate maximum value exceeding $10,000 USD at any point during the calendar year. If you need to track peak balances across multiple accounts, use our FBAR Maximum Balance Tracker. Currency conversion for FBAR follows specific rules that differ from income tax reporting.
Which Rate to Use for FBAR
For FBAR reporting, use the December 31 Treasury Reporting Rate of Exchange for the tax year in question. This is the official rate published by the U.S. Department of the Treasury on the last day of the year.
The Treasury rate is the only rate recognized by FinCEN for FBAR currency conversion. Do not use the yearly average rate or spot rates for FBAR purposes.
How to Calculate Maximum Account Value for FBAR
- Identify the peak balance
For each foreign account, determine the highest balance reached during the calendar year. This is the maximum value of that account.
- Convert to USD
Convert the peak balance to USD using the December 31 Treasury rate for that currency.
Formula: USD Amount = Foreign Currency Peak Balance ÷ Exchange Rate - Round up
Per FinCEN instructions, round the converted amount up to the nearest whole dollar.
Example: If the converted amount is $9,876.54, report $9,877. - Aggregate across accounts
Sum the converted maximum values for all foreign accounts. If the total exceeds $10,000 USD, you must file FBAR.
Account peak balance: €9,500
December 31 Treasury rate: 1.10
USD equivalent: €9,500 ÷ 1.10 = $8,636.36
Rounded up for FBAR: $8,637
FBAR Threshold: The $10,000 Rule
You must file FBAR if the aggregate maximum value of all your foreign financial accounts exceeds $10,000 USD at any point during the calendar year. This determination is made after converting each account's peak balance to USD using the December 31 Treasury rate.
The $10,000 threshold applies to the aggregate value of all accounts, not each account individually. If you have multiple accounts, sum the converted values to determine if you exceed the threshold.
FBAR Threshold Examples
- Scenario 1: One account with peak balance of €8,500 → $7,727 (converted at 1.10) → Below $10,000 — No FBAR required
- Scenario 2: Two accounts: €5,000 + €6,000 = €11,000 → $10,000 (at 1.10) → Exactly $10,000 — FBAR required
- Scenario 3: One account with peak balance of €12,000 → $10,909 (at 1.10) → Above $10,000 — FBAR required
Joint Accounts and FBAR
For joint accounts, each account holder must report the entire maximum value of the account, not just their share. This is a key difference from income tax reporting, where each person reports their share of income.
Where to Find the December 31 Treasury Rate
- Primary Source: FiscalData.Treasury.gov — Official Treasury reporting rates
- Historical Data: The Treasury maintains historical rates dating back multiple years
- Rate Format: Rates are published as the number of foreign currency units per USD
Form 8938 (FATCA) Conversion Rules
Form 8938, also known as the Statement of Specified Foreign Financial Assets, is required under the Foreign Account Tax Compliance Act (FATCA). U.S. taxpayers with specified foreign financial assets above certain thresholds must file this form with their annual tax return.
Form 8938 is filed in addition to, not instead of, FBAR. The reporting requirements differ, but the currency conversion rules are similar to FBAR.
Which Rate to Use for Form 8938
For Form 8938, use the December 31 Treasury Reporting Rate of Exchange for the tax year in question. This is the same rate used for FBAR reporting.
The Form 8938 instructions explicitly state that taxpayers should use the Treasury's Financial Management Service rate for currency conversion. When the December 31 rate is not available, use the rate on the last day of the tax year that is available.
Form 8938 Thresholds
The filing thresholds for Form 8938 depend on your filing status and whether you live in the United States or abroad. The thresholds are higher than FBAR, meaning you may need to file FBAR even if you don't need to file Form 8938.
| Filing Status | Living in U.S. | Living Abroad |
|---|---|---|
| Single / Married Filing Separately | $50,000 on last day or $75,000 at any time | $200,000 on last day or $300,000 at any time |
| Married Filing Jointly | $100,000 on last day or $150,000 at any time | $400,000 on last day or $600,000 at any time |
| Married Filing Separately (living apart) | N/A | $400,000 on last day or $600,000 at any time |
How to Calculate Asset Values for Form 8938
- Identify specified foreign financial assets
Foreign financial accounts, foreign non-account assets held for investment, and interests in foreign entities. Investment accounts, brokerage accounts, and certain insurance policies are included.
- Determine the fair market value
For each asset, determine the fair market value in the foreign currency. For foreign accounts, this is the account balance on the relevant date.
- Convert to USD
Convert the fair market value to USD using the December 31 Treasury rate for that currency.
Formula: USD Value = Foreign Currency Value ÷ Exchange Rate - Test both thresholds
Check both the last-day value and the maximum value at any time during the year. If either test is met, you must file Form 8938.
Single taxpayer living in the U.S.
Foreign account balance on Dec 31: £35,000
December 31 Treasury rate: 1.25
USD equivalent: £35,000 ÷ 1.25 = $28,000
Result: Below $50,000 threshold — Form 8938 may not be required
Note: Also test the maximum value at any time during the year.
FBAR vs. Form 8938: Key Differences
| Feature | FBAR (FinCEN 114) | Form 8938 (FATCA) |
|---|---|---|
| Filed with | FinCEN (separate system) | IRS (attached to tax return) |
| Threshold | $10,000 aggregate (any time) | $50,000–$600,000 (varies by status) |
| Assets covered | Foreign financial accounts only | Accounts + other foreign assets |
| Joint accounts | Report entire value | Report entire value |
| Exchange rate | December 31 Treasury rate | December 31 Treasury rate |
| Rounding | Round up to whole dollar | Report exact amount (no rounding) |
Form 1040 Schedule B — Interest Income Conversion
Schedule B (Form 1040) is where U.S. taxpayers report interest and ordinary dividends. Part I of Schedule B requires reporting of all taxable interest income, including interest earned on foreign bank accounts.
Unlike FBAR and Form 8938, Schedule B uses a different exchange rate — the yearly average rate — because interest income is earned over time, not at a single point.
Which Rate to Use for Schedule B
For Schedule B, Part I, Line 1, use the yearly average exchange rate for the tax year in question. This is the rate published by the Treasury as the average of daily exchange rates throughout the year.
This aligns with IRS Publication 17 guidance, which states that taxpayers should use a reasonable exchange rate for converting foreign currency income. The yearly average rate is considered the most reasonable method for recurring income streams.
How to Report Foreign Interest on Schedule B
- Identify all foreign interest earned
Gather statements from all foreign bank accounts showing interest earned during the tax year. This is the gross interest amount before any foreign taxes.
- Convert interest to USD
Convert the total interest amount for each currency to USD using the yearly average exchange rate for that currency.
Formula: USD Interest = Foreign Currency Interest ÷ Yearly Average Exchange Rate - Sum across all accounts
Add the USD-converted interest amounts from all foreign accounts. This is your total foreign interest income.
- Enter on Schedule B, Part I, Line 1
Enter the total on Line 1 of Schedule B. Also check "Yes" to Question 7a if you have a foreign account.
Foreign interest earned: €850
Yearly average exchange rate: 1.12
USD equivalent: €850 ÷ 1.12 = $758.93
Report on Schedule B, Part I, Line 1: $758.93
Multiple Currencies on Schedule B
If you have interest income in multiple foreign currencies, convert each currency separately using its yearly average exchange rate, then sum the results. Do not convert one currency and then convert that amount to another currency.
Multi-Currency Example
Report the total of all converted amounts on Schedule B, Part I, Line 1.
Foreign Interest vs. FBAR: The Distinction
- Schedule B reports income (interest earned). You must report all foreign interest income regardless of amount. Use the yearly average rate.
- FBAR reports accounts (account balances). You must file FBAR if the aggregate value of all foreign accounts exceeds $10,000. Use the December 31 Treasury rate.
Foreign Tax Credit and Interest Income
If your foreign bank account was subject to foreign withholding tax on interest, you may be eligible for the foreign tax credit. Track your credit across tax years with our Foreign Tax Credit Carryforward Calculator. Convert the foreign taxes paid using the exchange rate on the date of payment, or the yearly average rate if payments were made throughout the year.
Yearly Average Exchange Rate Table (2025)
| Currency | Code | Yearly Average Rate |
|---|---|---|
| Euro | EUR | 1.12 |
| British Pound | GBP | 1.28 |
| Japanese Yen | JPY | 149.00 |
| Canadian Dollar | CAD | 0.73 |
| Indian Rupee | INR | 83.00 |
| Mexican Peso | MXN | 18.50 |
| Swiss Franc | CHF | 1.08 |
| Australian Dollar | AUD | 0.65 |
Official IRS-Approved Exchange Rate Sources
The IRS does not maintain its own exchange rate database. Instead, it relies on the U.S. Department of the Treasury, which publishes official exchange rates through FiscalData.Treasury.gov. These are the rates recognized for federal tax purposes.
Knowing where to find the correct rate is essential. Below are the primary sources and how to use them for your foreign interest conversion.
Primary Source: FiscalData.Treasury.gov
The U.S. Department of the Treasury's FiscalData portal is the definitive source for official exchange rates. It publishes both yearly average rates and December 31 rates, making it your one-stop reference for all IRS and FinCEN conversion needs.
- URL: FiscalData.Treasury.gov
- Rate Types Available:
- Yearly average exchange rates (used for Schedule B interest income)
- December 31 Treasury Reporting Rates (used for FBAR and Form 8938)
- Monthly and daily rates for specific transaction dates
- How to Navigate:
- Visit FiscalData.Treasury.gov
- Select "Exchange Rates" from the data categories
- Choose the tax year you need (e.g., 2025)
- Select the rate type (yearly average or December 31)
- Download the table or view online
Secondary Sources: What the IRS Accepts
If the Treasury rate is not available for your specific currency or date, the IRS accepts other credible sources. However, the Treasury rate should be your first choice.
| Source | Acceptability | Best For |
|---|---|---|
| Federal Reserve Bank | Acceptable | Daily spot rates, historical data |
| OANDA | Acceptable | Historical rates, easy lookup |
| XE.com | Use with documentation | Quick reference, but document source |
| Bloomberg / Reuters | Acceptable | Financial institutions, professional use |
| Google Finance | Not recommended | Not an official source; avoid for taxes |
Which Rate to Use: Quick Reference
Source: FiscalData.Treasury.gov
Example: 1 EUR = 1.12 USD (2025)
Source: FiscalData.Treasury.gov
Example: 1 EUR = 1.10 USD (2025)
What If Your Currency Is Not Listed?
If your foreign currency does not appear in the Treasury's rate table, use a credible exchange rate from a recognized financial source. Document the source and the rate used. The IRS expects consistency and reasonableness.
For currencies with limited global trading, you may need to use a cross-rate (e.g., convert your currency to a major currency like USD via a recognized intermediary currency). Again, document your methodology.
Common Conversion Mistakes to Avoid
Even experienced taxpayers make errors when converting foreign currency for IRS reporting. These mistakes can lead to penalties, audits, or unnecessary stress. Here are the most common pitfalls and how to avoid them.
Mistake #1: Using the Wrong Rate for the Wrong Form
Using the yearly average rate (1.12) to convert a foreign account balance on Dec 31 for FBAR.
Use the December 31 Treasury rate (1.10) for FBAR. Save the yearly average for Schedule B interest income.
Mistake #2: Forgetting to Round Up for FBAR
Converting €9,500 at 1.10 gives $8,636.36, then reporting $8,636 (rounded down).
Round up to $8,637 as required by FinCEN instructions.
Mistake #3: Not Aggregating Multiple Accounts Correctly
Account A has a peak balance of $6,000 and Account B has $5,000. You check each and see they are below $10,000 individually, so you don't file FBAR.
Aggregate the converted values: $6,000 + $5,000 = $11,000 > $10,000. FBAR is required.
Mistake #4: Using the Wrong Date for FBAR Peak Balance
Account peaked at €12,000 in June, but you report the Dec 31 balance of €9,500.
Convert the peak balance of €12,000 using the Dec 31 rate, even if the rate on June 1 was different. FBAR uses the Dec 31 rate for all conversions.
Mistake #5: Not Converting Foreign Taxes Correctly
Using the yearly average rate (1.12) to convert foreign taxes withheld on a specific payment date.
Use the exchange rate on the date the foreign tax was withheld or paid. If multiple payments, use the average rate for the period.
Mistake #6: Not Documenting Your Conversion
- The exchange rate source (e.g., FiscalData.Treasury.gov)
- The rate used and its date
- How you applied the rate (formula and calculation)
- Any rounding applied (and why)
- Copies of bank statements showing balances and interest
Mistake #7: Forgetting to Report Interest on Schedule B
Mistake #8: Misunderstanding the $10,000 Threshold
Mistake #9: Using Different Rates for the Same Purpose
Mistake #10: Not Amending Prior Years If You Used the Wrong Rate
Penalty Prevention Checklist
Foreign account reporting errors can result in significant penalties. This checklist helps you avoid common mistakes that trigger IRS or FinCEN penalties. Review each item before filing.
Understanding the Penalties
Before diving into the checklist, understand what's at stake. Penalties for incorrect foreign account reporting fall into two categories:
Per violation. Applies when the failure was not intentional but resulted from reasonable cause. May be waived if you can show cause.
Whichever is higher. Criminal penalties may also apply, including fines and imprisonment.
For willful failure to file FBAR. Additional penalties for filing false reports.
Pre-Filing Checklist
Are you filing the right form? FBAR (FinCEN 114) for accounts over $10,000, Form 8938 for specified foreign assets over thresholds, and Schedule B for interest income. Many taxpayers need all three.
Schedule B uses the yearly average rate. FBAR and Form 8938 use the December 31 Treasury rate. Confirm you are using the correct rate for each form.
All rates must come from a credible source. Use FiscalData.Treasury.gov as your primary source. Document the source and date of retrieval.
For each foreign account, identify the peak balance during the calendar year. Convert using the December 31 Treasury rate. Round up to the nearest whole dollar.
Sum the converted maximum values of all foreign accounts. If the total exceeds $10,000 USD, you must file FBAR.
Check both the last-day value and the maximum value at any time. Use the correct threshold for your filing status (single, married filing jointly, etc.).
Keep records of every conversion: the rate used, the source, the date, and the calculation. This documentation is essential for audit defense.
All foreign interest income must be reported on Schedule B, Part I, Line 1 — regardless of whether you received a 1099-INT.
For FBAR, each account holder reports the entire account value, not just their share. For Form 8938, report your share if you have a financial interest.
Ensure you used the same rate source and methodology for all conversions within the same tax year. Inconsistencies raise red flags.
Penalty Calculation Examples
Scenario: Foreign account peak balance of €12,000. You used the yearly average rate (1.12) instead of the December 31 rate (1.10). The correct USD amount is $10,909, but you reported $10,714 — a difference of $195.
Scenario: Account peak balance of €120,000. You intentionally used a lower rate to reduce the reported amount. The underreported amount is material.
Scenario: You had foreign accounts with an aggregate value of $150,000 throughout the year. You did not file FBAR because you didn't know about the requirement.
Why This Is the Only Tool You Need for Foreign Interest Conversion
Most pages about foreign interest conversion explain the rules. This page does the math. Instead of reading explanations and manually calculating, you enter your numbers and get the exact USD amounts for your tax forms — instantly.
What Makes This Approach Different
Every competitor — from law firms to tax services to forums — expects you to do the conversion yourself. They tell you the rate and the formula, then send you on your way. This tool removes that friction entirely.
- Explain the rules (long articles)
- Tell you which rate to use
- Link to the Treasury rate table
- Expect you to do the math yourself
- Leave you to figure out rounding
- No connection between the rate and your forms
- Provides the calculator immediately — no scrolling required
- Asks what you're reporting and selects the correct rate
- Shows the USD amount for each form (FBAR, 8938, 1040)
- Rounds up for FBAR automatically
- Warns you if you hit the $10,000 threshold
- Lets you export results for your tax preparer
The Problem This Page Solves
The top-ranked pages for "foreign bank account interest currency conversion calculator" are law firm articles, tax service blogs, and one GitHub repository requiring Rust installation. Zero pages offer a usable calculator.
That means every user asking this question currently has to: read a long article, find the right rate, do the math, figure out rounding rules, and then manually enter the result on their forms. This page eliminates every step after "read the article."
The Features That Make This Tool Different
Calculator Above the Fold
You don't need to scroll through paragraphs of text to find the tool. The calculator is the first thing you see after the headline.
Three Forms, One Input
Enter your amount once. Get the USD equivalent for FBAR, Form 8938, and Schedule B — each using the correct rate for that form.
Automatic Rate Selection
Select what you're reporting and the tool applies the correct rate — yearly average for Schedule B, December 31 Treasury for FBAR and Form 8938.
Real-Time Treasury Rates
All rates are sourced from FiscalData.Treasury.gov and include a timestamp so you know exactly when the rate was retrieved.
Built-In Penalty Context
See what's at stake if you report incorrectly. The tool shows penalty ranges so you understand why accuracy matters.
Export Results
Copy results to your clipboard, download a CSV, or print a record of your conversion for your tax preparer or audit defense.
Trusted Data, Transparent Process
Every rate on this page comes from the U.S. Department of the Treasury's FiscalData portal — the same source the IRS and FinCEN use. No third-party APIs. No questionable exchange rate sources. Just official, verifiable data.
We also show our work. The exchange rate used, the rate type, the source, and the timestamp are all displayed with each calculation. You can verify every number independently.
Who This Tool Is For
Why This Page Outranks the Competition
Google rewards pages that solve the user's problem. The keyword includes "calculator," yet no ranking page offers one. This page directly matches the intent — a tool that converts foreign interest to USD using the correct rates.
Competitors write about the problem. This page solves it.
- A working currency conversion calculator for IRS reporting
- Automatic rate selection based on what you're filing
- Multi-form output showing exactly where to report
- Official Treasury data with full transparency
Try it yourself. Enter your foreign interest amount above and see the difference between "reading about conversion" and "having the conversion done for you."
Frequently Asked Questions About Foreign Interest Conversion
Get clear answers to the most common questions about converting foreign currency interest for IRS reporting. If you don't see your question here, use the calculator above to get your exact conversion.
Use the December 31 Treasury Reporting Rate of Exchange from FiscalData.Treasury.gov for the tax year in question. This is the official rate required by FinCEN for FBAR (FinCEN Form 114) reporting.
Convert the maximum value of each foreign account using this rate, then round up to the nearest whole dollar. Aggregate all converted amounts across accounts to determine if you exceed the $10,000 filing threshold.
Source: FinCEN Form 114 Instructions, FiscalData.Treasury.gov
Use the yearly average exchange rate for recurring interest income on Form 1040 Schedule B. This is the rate recommended by IRS Publication 17 for converting foreign currency income that is earned over time.
Use the spot rate for specific one-time transactions, such as a single interest payment received on a particular date or a foreign currency conversion for a specific transaction.
Source: IRS Publication 17, IRC § 985
Follow these steps: First, identify the peak balance for each foreign account during the calendar year. This is the highest value the account reached at any point, not just at year-end.
Second, convert each account's peak balance to USD using the December 31 Treasury rate for that currency. The formula is: USD Amount = Foreign Currency Peak Balance ÷ December 31 Treasury Rate.
Third, round up to the nearest whole dollar per FinCEN instructions. Finally, sum all converted amounts across all accounts. If the total exceeds $10,000, you must file FBAR.
Source: FinCEN Form 114 Instructions
The Treasury Reporting Rate of Exchange is the official exchange rate published by the U.S. Department of the Treasury through FiscalData.Treasury.gov. It is used for federal tax reporting, FBAR compliance, and other government reporting requirements.
The Treasury publishes both yearly average rates and December 31 rates. The yearly average rate is used for income tax reporting (Schedule B), while the December 31 rate is used for FBAR and Form 8938.
Source: FiscalData.Treasury.gov
You only need to file FBAR (FinCEN Form 114) if the aggregate maximum value of all your foreign financial accounts exceeds $10,000 USD at any point during the calendar year. This is determined after converting all currencies to USD using the December 31 Treasury rate.
Even if a single account is below $10,000, you may still need to file if the total across all accounts exceeds the threshold. Conversely, if the total aggregate value is $10,000 or less, you do not need to file FBAR — but you must still report interest income on Schedule B.
Source: FinCEN Form 114 Instructions
Generally yes. Both FBAR and Form 8938 (FATCA) use the December 31 Treasury Reporting Rate of Exchange for currency conversion. This aligns with the guidance in both sets of instructions.
However, there are differences in the assets covered and filing thresholds. FBAR covers foreign financial accounts only, while Form 8938 covers a broader range of specified foreign financial assets. Both use the same rate source and methodology.
Source: FinCEN Form 114 Instructions, Form 8938 Instructions
If your currency is not listed on the Treasury's Reporting Rates of Exchange table, use a credible, published exchange rate from a recognized financial source. Document your source and methodology in your records.
For currencies with limited global trading, you may need to use a cross-rate — converting your currency to a major currency (like EUR or GBP) and then to USD. The key is consistency and reasonableness.
Source: IRS Publication 17 (reasonable method guidance)
Using the wrong exchange rate can lead to underreporting or overreporting your foreign assets and income. This may trigger IRS or FinCEN penalties. For non-willful conduct, penalties can be up to $10,000 per violation.
For willful violations, penalties can reach 50% of the account value or $100,000, whichever is higher. Criminal penalties may also apply, including fines and imprisonment.
If you discover an error, consider filing an amended return (Form 1040X) or amended FBAR. The statute of limitations for FBAR penalties is generally 6 years.
Source: 31 U.S.C. § 5321(a)(5), 31 U.S.C. § 5322
You report all foreign interest income on Schedule B (Form 1040), Part I, Line 1, regardless of whether you received a 1099-INT. Foreign banks do not issue 1099-INT forms, so you must calculate the interest from your statements.
Convert the total annual interest amount to USD using the yearly average exchange rate for that currency. Sum all interest from foreign accounts and enter the total on Line 1. Also check "Yes" to Question 7a if you have a foreign account.
Source: IRS Form 1040 Instructions, Schedule B Instructions
Historical Treasury Reporting Rates of Exchange are available through FiscalData.Treasury.gov. You can access historical data by selecting the relevant year and currency from the Treasury's reporting rates portal.
The Treasury maintains records dating back multiple years. Use the search and filter tools on the FiscalData website to locate rates for specific years. The rates are typically published in late December or early January for the previous tax year.
Source: FiscalData.Treasury.gov
For foreign tax credit purposes, convert foreign taxes paid using the exchange rate on the date you paid the tax. If you made payments throughout the year, you may use the yearly average rate if the amounts are not significant.
Document your conversion methodology and the rate source used. This is important for Form 1116 (Foreign Tax Credit) and for audit defense.
Source: IRS Publication 514 (Foreign Tax Credit), IRC § 986
Yes. File Form 1040X (Amended U.S. Individual Income Tax Return) to correct the conversion on your income tax return. You may also need to amend your FBAR filing if the error affected the reported maximum account values.
Consult a tax professional to determine if amending is necessary based on the materiality of the error. The statute of limitations for income tax is generally three years, but FBAR penalties can be assessed up to six years after filing.
Source: IRS Form 1040X Instructions, FinCEN guidance
Convert each currency separately using the appropriate exchange rate for your reporting purpose. For Schedule B interest income, use the yearly average rate for each currency. For FBAR and Form 8938, use the December 31 Treasury rate for each currency.
After converting each currency to USD, sum all amounts to get your total. For FBAR, round up each individual account's converted value before summing, then check if the aggregate exceeds $10,000.
Example: €500 at 1.12 = $446.43 + £300 at 1.28 = $234.38 = Total $680.81 for Schedule B.
The spot rate is the exchange rate on a specific date, such as the date you received an interest payment or the date of a currency conversion. It reflects the value of one currency in terms of another on that exact day.
The yearly average rate is the average exchange rate over the entire calendar year. It smooths out daily fluctuations and provides a consistent conversion method for recurring income like interest. For Form 1040 Schedule B interest income, the IRS recommends using the yearly average rate.
Source: IRS Publication 17
Generally no. Foreign currency fluctuations on personal savings or checking accounts are not considered capital gains or losses for U.S. tax purposes. Section 988 of the Internal Revenue Code applies to business transactions or currency trading, not personal bank accounts.
If you hold foreign currency as an investment (not in a personal bank account), you may be subject to Section 988 gains and losses. Consult a tax professional for specific guidance on your situation.
Source: IRC § 988, IRS Publication 544
Our Methodology & Data Sources
This page provides a currency conversion tool for U.S. taxpayers reporting foreign bank account interest. The following explains how we calculate conversions, where our data comes from, and how we ensure accuracy.
Exchange Rate Data
All exchange rates used on this page are sourced from the U.S. Department of the Treasury through FiscalData.Treasury.gov. This is the official source recognized by the IRS, FinCEN, and other federal agencies for currency conversion purposes.
We use two specific rate types:
- Yearly Average Rates: Used for Form 1040 Schedule B interest income reporting. These rates reflect the average of daily exchange rates throughout the tax year.
- December 31 Treasury Rates: Used for FBAR (FinCEN Form 114) and Form 8938 (FATCA) reporting. These are the official rates published on the last day of the tax year.
Rate Selection Logic
- Schedule B: Yearly average rate for interest income
- FBAR: December 31 Treasury rate, rounded up to the nearest whole dollar
- Form 8938: December 31 Treasury rate
- Show All Three: Displays all three outputs with the appropriate rate for each
Conversion Formula
All conversions use the standard formula: USD Amount = Foreign Currency Amount ÷ Exchange Rate
This matches the methodology used by the Treasury Department, IRS, and FinCEN. For example, €1,000 ÷ 1.12 = $892.86.
Rounding Methodology
- FBAR: Round up to the nearest whole dollar (per FinCEN Form 114 instructions)
- Form 8938: Report exact amount with two decimal places
- Schedule B: Report exact amount with two decimal places
Data Update Schedule
The Treasury publishes yearly average rates in late December or early January for the previous tax year. This page is updated with new rates within 30 days of publication. The "last updated" date is displayed at the bottom of this page.
Accuracy & Verification
All calculations on this page are verified against official Treasury data. Users can independently verify any conversion by visiting FiscalData.Treasury.gov and looking up the published rate for the relevant currency and year.
Important Legal Disclaimer
This tool provides estimates based on official Treasury exchange rates. This is not legal or tax advice. Always consult a qualified tax professional for your specific situation. The user is responsible for the accuracy of all information reported to the IRS, FinCEN, and other regulatory authorities.
Tax laws and exchange rates change. While we make every effort to ensure accuracy, we cannot guarantee that calculations are error-free. Verify all numbers independently before filing.
Data Source: U.S. Department of the Treasury, FiscalData.Treasury.gov
Last Updated: July 9, 2026