2026-02-21
How to Track Investments in Multiple Currencies
If you hold investments in more than one currency, you already know the problem: no single app, broker, or spreadsheet gives you a clear picture of what you actually own. Your US brokerage shows USD values. Your European ETF platform shows EUR. Your crypto wallet shows BTC and ETH. And your savings account in Thailand shows THB.
The result is a fragmented view of your finances that makes it nearly impossible to answer the most basic question in personal finance: what is my net worth, right now, in the currency I actually think in?
This guide covers the practical mechanics of multi-currency investment tracking — what breaks, why it breaks, and how to set up a system that gives you accurate, consolidated numbers.
Why Multi-Currency Tracking Is Harder Than It Looks¶
Single-currency investors have it easy. If you earn in USD, invest in USD-denominated stocks, and spend in USD, your brokerage statement is your portfolio tracker. The numbers are the numbers.
Once you introduce a second currency, everything changes. Your portfolio’s value now depends on two independent variables: the performance of the underlying asset and the exchange rate between the asset’s currency and your home currency. A stock can go up 8% and still lose you money if the currency it trades in fell 10% against yours.
This is not a theoretical concern. Between 2021 and 2023, the euro fell roughly 15% against the US dollar. A European investor holding S&P 500 index funds saw amplified gains. An American holding European equities saw a chunk of their returns erased — even when those stocks performed well in local terms.
Multi-currency tracking requires you to handle several things simultaneously:
- Live exchange rates between every currency pair in your portfolio
- Consistent conversion of all assets to a single home currency
- Historical FX tracking to understand how exchange rates affected past returns
- Correct cost basis in both the asset’s local currency and your home currency
Most tools do none of this well.
Why Spreadsheets Fail at Multi-Currency Tracking¶
Spreadsheets are the first tool most international investors reach for, and they work for about three months before becoming unmanageable.
The core problem is that exchange rates are not static. A spreadsheet snapshot from last Tuesday is already wrong by Wednesday. You can use GOOGLEFINANCE or similar functions to pull live FX rates, but these introduce their own issues:
Rate limits and reliability. GOOGLEFINANCE is not a financial data API. It is a convenience function that breaks regularly, returns stale data, and has no SLA. Google explicitly states it should not be used for trading or financial decisions.
No historical rate tracking. When you want to know what your portfolio was worth three months ago, you need the FX rates from three months ago — not today’s rates applied retroactively. Spreadsheets cannot do this without manual data entry.
Formula complexity compounds. With 3 currencies, you need 3 conversion formulas. With 8 currencies, you need 8. Each new holding requires updating formulas across multiple sheets. One misplaced cell reference silently corrupts your data, and you will not notice for weeks.
No time-series consistency. To track performance over time, you need daily or weekly snapshots of both asset prices and FX rates. In a spreadsheet, this means either manual data entry (unsustainable) or increasingly fragile automation (IMPORTDATA, Apps Script) that breaks when the source changes format.
If you have investments in more than three currencies or more than ten positions, a spreadsheet will cost you more time than it saves within a few months.
Step 1: Choose a Home Currency¶
Every multi-currency portfolio needs a single base currency — the lens through which you view everything. This is not about which currency is “best.” It is about consistency.
Your home currency should be:
- The currency you spend the most in your daily life. If you are living in Thailand and paying rent in baht, THB might be your home currency — even if you earn in USD.
- The currency you file taxes in. If you are a US citizen abroad, the IRS requires reporting in USD regardless of where you live. The IRS provides annual average exchange rates for conversion at irs.gov/individuals/international-taxpayers/yearly-average-currency-exchange-rates.
- The currency you think in. This sounds vague, but it matters. If you mentally convert everything to GBP before making a financial decision, GBP is your home currency.
For most expats and digital nomads, the home currency is the one tied to their tax residency or their longest-term financial obligations (mortgage, retirement accounts, etc.).
Once you choose a home currency, every asset in your portfolio gets converted to that currency for reporting purposes. The underlying asset stays denominated in its original currency — you are not selling or converting anything. You are simply viewing the consolidated value through a single lens.
Step 2: Inventory Every Account and Asset¶
Before you can track anything, you need to know what you have. This sounds obvious, but international investors frequently forget accounts.
Go through each of these categories:
Brokerage accounts. US-based (Schwab, Fidelity, Interactive Brokers), European (Degiro, Saxo, Trading 212), Asian (Tiger Brokers, moomoo), or wherever else you hold securities.
Retirement accounts. 401(k), IRA, SIPP, Superannuation, CPF, or equivalent. These are often forgotten in tracking because they feel “locked away,” but they are real assets. If you have US retirement accounts and live in the United Kingdom, both the IRS and HMRC may want to know about them.
Crypto wallets and exchanges. On-chain wallets, exchange balances, staking positions.
Cash accounts. Every bank account in every country. If you are a nomad with bank accounts in three countries — common for people who have lived in Portugal, Germany, or Singapore — list them all.
Real property. If you own real estate, its estimated value belongs in your net worth calculation, denominated in the local currency of the property.
Debt. Mortgages, student loans, personal loans, credit card balances. These are negative line items, and they matter especially when denominated in a different currency than your income.
Write everything down with the currency each account is denominated in. This becomes your tracking inventory.
Step 3: Set Up Consolidated Reporting¶
With your inventory complete, you need a system that does three things:
- Pulls current prices for each asset (stocks, ETFs, crypto)
- Pulls current FX rates for each currency pair
- Converts everything to your home currency and displays the total
The conversion math is straightforward. If you hold 100 shares of a stock trading at EUR 45, and the EUR/USD rate is 1.08, the value in USD is:
100 shares x EUR 45 x 1.08 = USD 4,860
The challenge is doing this for every position, with live data, every day, without manual effort.
FlashFi does this automatically. You set your home currency once, add your holdings in whatever currency they trade in, and the multi-currency engine handles conversion using live exchange rates. Your dashboard shows your total portfolio value, net worth, and allocation — all in your home currency.
Step 4: Understand FX Impact on Every Position¶
Once you have consolidated reporting, the next step is understanding how much of each position’s return comes from the asset itself versus the currency movement.
Consider a concrete example. You bought a UK ETF at GBP 100 when GBP/USD was 1.27. Three months later, the ETF is at GBP 108 (up 8%), but GBP/USD has dropped to 1.22.
- Local return: +8% (GBP 100 to GBP 108)
- Value at purchase in USD: GBP 100 x 1.27 = USD 127
- Value now in USD: GBP 108 x 1.22 = USD 131.76
- Home currency return: +3.7%
Nearly half of your local gain was eaten by the currency movement. Without tracking both the asset price and the exchange rate, you would think you made 8%. You actually made 3.7% in the currency you spend.
This is the kind of insight that single-currency tools completely miss. For a deeper explanation of these mechanics, see How Currency Exchange Rates Affect Your Investment Returns.
Step 5: Track Cost Basis Correctly¶
Cost basis in a multi-currency portfolio has an extra layer of complexity. You need to track:
- The price you paid in the asset’s local currency (for calculating local returns)
- The exchange rate on the date of purchase (for calculating home currency cost basis)
- The exchange rate today (for calculating current home currency value)
This matters for tax purposes. In the US, the IRS expects capital gains to be reported in USD, meaning your cost basis must be the USD-equivalent value on the date of purchase — not the local currency amount converted at today’s rate. See IRS Publication 550 for the rules on reporting foreign investment income.
If you bought shares in a Japanese stock for JPY 500,000 when USD/JPY was 110, your cost basis is USD 4,545. If you sell those shares for JPY 550,000 when USD/JPY is 150, your proceeds are USD 3,667. You made money in yen but lost money in dollars — and the IRS sees a capital loss.
A proper multi-currency tracker records the FX rate at the time of each transaction, not just the current rate. This gives you accurate cost basis in your home currency without manual calculation.
Step 6: Automate Snapshots for Historical Tracking¶
Point-in-time tracking is necessary but not sufficient. You also need to see how your portfolio has changed over time.
This requires regular snapshots — a record of your total portfolio value (in your home currency) at consistent intervals. Daily snapshots are ideal, weekly is acceptable.
Snapshots let you answer questions like:
- How has my net worth changed over the past 6 months?
- How much of my portfolio’s movement was driven by FX versus asset performance?
- Am I actually making progress toward my financial goals, or am I treading water?
Without historical snapshots, you are flying blind. You know where you are today, but you cannot see the trajectory.
FlashFi takes automatic snapshots of your net worth at regular intervals, giving you a time-series chart of your consolidated portfolio value in your home currency.
Common Mistakes in Multi-Currency Tracking¶
Mixing up rate directions. EUR/USD = 1.08 means 1 euro costs 1.08 dollars. USD/EUR = 0.926 means 1 dollar costs 0.926 euros. Confusing these will silently double or halve your values. Pick one convention and stick with it.
Ignoring transaction fees and spreads. When you actually convert currency (not just tracking paper values), the real exchange rate you get is worse than the mid-market rate. Your bank or broker takes a spread. Track the actual rate you received, not the Google rate.
Forgetting about currency in retirement accounts. Your 401(k) is denominated in USD even if you live in Colombia. It still needs to be converted to your home currency for a complete picture.
Tracking in “whatever currency the broker shows.” Each broker shows values in its default currency. If you simply add these numbers together without converting, your net worth is meaningless — you are adding dollars to euros to pounds.
What a Proper Setup Looks Like¶
A well-configured multi-currency tracking system gives you:
- One number for your total net worth, in your home currency, updated with live FX rates
- Per-position returns that show both local performance and home-currency performance
- Historical charts that reflect actual consolidated value over time, not reconstructed estimates
- Cost basis tracked at the FX rate on the date of each transaction
- Currency allocation showing how much of your portfolio is exposed to each currency
If your current setup does not provide all five, you are making decisions with incomplete information.
Start Tracking Properly¶
FlashFi was built specifically for investors who hold assets in multiple currencies. Set your home currency, add your holdings, and get a consolidated view of your entire portfolio — stocks, ETFs, crypto, cash, and debt — all converted to your home currency with live exchange rates.
Start tracking your multi-currency portfolio and see your real net worth for the first time.
By David Brougham