2026-02-21

How to Track Real Estate Investments Across Countries

Real estate is the largest single asset most people own, and for international investors it is also the most poorly tracked. If you own property in one country and live in another, your net worth calculation is incomplete without it. But including real estate in a multi-currency portfolio raises questions that stocks and ETFs do not: How do you value a property when there is no live market price? Which currency do you denominate it in? How do you account for the mortgage? And what happens to your net worth when the exchange rate between your property’s currency and your home currency shifts by 10%?

This guide covers the practical mechanics of tracking real estate investments across countries — valuation methods, currency handling, mortgage and equity tracking, rental income, and the tax implications you need to know about.

Why Real Estate Belongs in Your Net Worth

Some investors exclude property from their portfolio tracking because it feels different from liquid investments. You cannot sell a fraction of your apartment the way you sell shares of an ETF. Valuations are estimates, not market prices. Transactions take months, not seconds.

But excluding real estate means your net worth is wrong. For many international investors, property represents 30% to 60% of their total wealth. Ignoring it gives you a distorted picture of your financial position, your asset allocation, and your currency exposure.

If you own a EUR 400,000 apartment in Portugal and a USD 200,000 stock portfolio, your actual asset allocation is roughly 65/35 real estate to equities (depending on the EUR/USD rate). If you only track the stocks, you think you have a $200,000 portfolio. In reality, you have a $650,000+ net worth with heavy concentration in a single illiquid asset denominated in a foreign currency. Those are materially different financial pictures that lead to different decisions.

Valuation Methods for International Property

Unlike publicly traded securities, real estate does not have a live market price. You need to choose a valuation method and apply it consistently. There are four common approaches, each with trade-offs.

Purchase Price

The simplest method. You record the property at the price you paid and leave it there until you sell or get a new appraisal. This is conservative and defensible — you know this number is real because you actually paid it.

When it works: For properties held short-term (under 3 years) or in stable markets where prices have not moved significantly.

When it fails: Over longer holding periods, purchase price diverges from reality. If you bought a flat in Germany in 2015 for EUR 180,000 and it is now worth EUR 320,000, carrying it at purchase price understates your net worth by EUR 140,000.

Government Assessed Value

Most countries assess property values for tax purposes. In the United States, county assessors publish assessed values that are typically available online. In the United Kingdom, the Valuation Office Agency (VOA) assigns council tax bands based on property values, though these are famously outdated (last revalued in 1991 in England). In Spain, the valor catastral (cadastral value) is used for property tax calculations and is publicly accessible.

When it works: As a conservative baseline. Assessed values tend to lag market values, so they rarely overstate what a property is worth.

When it fails: Assessed values can be wildly disconnected from market reality. A property assessed at EUR 150,000 for tax purposes might sell for EUR 250,000. In countries where reassessments are infrequent, the gap widens over time.

Market Estimate from Online Platforms

Platforms like Zillow (US), Zoopla and Rightmove (UK), Idealista (Spain, Portugal, Italy), and Immobilienscout24 (Germany) provide automated valuation models (AVMs) that estimate property values based on comparable sales, location, and property characteristics.

When it works: For residential property in markets with high transaction volumes and good data coverage. Zillow’s Zestimate, for example, has a median error rate of about 2.4% for on-market homes and 7.5% for off-market homes, according to Zillow’s published accuracy data.

When it fails: In markets with low transaction volumes, unique properties, or incomplete data. A villa in rural Croatia or a condo in Medellin may not have enough comparable sales for an AVM to produce a meaningful estimate.

Professional Appraisal

A licensed appraiser inspects the property and provides a formal valuation. This is the most accurate method and the only one that lenders, courts, and tax authorities typically accept as definitive.

When it works: Always, if you are willing to pay for it. Appraisals cost USD 300 to 600 in the US, GBP 250 to 500 in the UK, and vary widely elsewhere.

When it fails: The cost and effort make annual appraisals impractical for most people. Getting an appraisal every 2 to 3 years and using market estimates in between is a reasonable compromise.

The Practical Approach

For ongoing portfolio tracking, use market estimates from online platforms and update them quarterly. If no platform covers your market, use purchase price adjusted by a regional price index. The OECD publishes quarterly residential property price indices for 46 countries at oecd.org/housing/data, which you can use to apply a rough annual adjustment. Get a professional appraisal if you are refinancing, selling, or making major financial decisions based on the property’s value.

Whatever method you choose, be consistent. Switching between methods makes your net worth time series meaningless because you cannot tell whether changes reflect actual value movement or just a different measurement approach.

Handling Property in Different Currencies

The currency dimension is what makes cross-border real estate tracking genuinely difficult. Your property has a value in its local currency, but your net worth is calculated in your home currency. These two numbers move independently.

Suppose you own a property worth THB 8,000,000 in Thailand and your home currency is USD. At USD/THB = 33, that property is worth USD 242,424. If the baht weakens to USD/THB = 36, the same property — unchanged in local value — is now worth USD 222,222. Your net worth just dropped by $20,000 without anything happening to the property itself.

This is the same FX exposure that affects international stock holdings, but with real estate the amounts are typically much larger and the asset is illiquid. You cannot hedge a property the way you might hedge a foreign stock position.

For a deeper look at how currency movements affect investment values, see How Currency Exchange Rates Affect Your Investment Returns.

The correct way to track international property in your portfolio:

  1. Record the value in the property’s local currency. A flat in Portugal is denominated in EUR. A condo in Mexico is denominated in MXN. Do not convert at purchase and then freeze the number.
  2. Convert to your home currency using the current exchange rate. This should happen automatically in your tracking system, just as it does for foreign-denominated stocks.
  3. Update the local currency value periodically. Quarterly updates using market estimates or annual updates using price indices are sufficient for most people.
  4. Track the FX impact separately. When your property’s home-currency value changes, know how much came from the property’s local value changing versus the exchange rate changing. This tells you whether you have a real estate problem or a currency problem.

Mortgage and Equity Tracking

If you financed the property with a mortgage, you do not own the full value — you own the equity. Equity is the difference between the property’s current value and the outstanding mortgage balance. Both figures must be tracked and converted to your home currency.

Consider an example. You own a property worth GBP 350,000 in the United Kingdom with a GBP 220,000 mortgage. Your equity is GBP 130,000. If your home currency is USD and GBP/USD is 1.26, your equity in home currency terms is USD 163,800.

Both the asset (property value) and the liability (mortgage) should appear separately in your net worth calculation:

As you make mortgage payments, the liability decreases and your equity increases — even if the property value stays flat. Track the outstanding mortgage balance and update it whenever you get a statement from your lender, typically monthly.

There is a subtle currency dynamic here for cross-border mortgages. If your property is in the Eurozone with a EUR mortgage but you earn in USD, a strengthening dollar means your mortgage (in dollar terms) gets cheaper to service. Conversely, a weakening dollar makes those monthly payments more expensive in real terms. This is a real risk that has caught many expats off guard, particularly British expats with EUR mortgages during the post-Brexit pound decline.

Tracking Rental Income in Foreign Currencies

If you rent out a property abroad, the rental income adds another currency flow to track. Rental income arrives in the property’s local currency and needs to be:

  1. Recorded in the local currency — the actual amount received
  2. Converted to your home currency — for consolidated income reporting
  3. Net of expenses — property management fees, maintenance, insurance, HOA/community fees, and local property taxes

For a property in Mexico generating MXN 25,000 per month in rent with MXN 8,000 in monthly expenses, your net rental income is MXN 17,000. At USD/MXN = 17.5, that is roughly USD 971 per month. If the peso weakens to USD/MXN = 20, the same MXN 17,000 is now worth USD 850. Your rental yield in home currency terms just dropped by 12% without any change in the local rental market.

Track rental income monthly and convert it at the exchange rate on the date received, not at an average rate. This gives you an accurate picture of the cash flow your international property is actually generating in the currency you spend.

Tax Implications of Cross-Border Property Ownership

Owning property abroad creates tax obligations in multiple jurisdictions. The specifics vary by country, but there are common patterns you need to be aware of.

Where You Owe Property Tax

You almost always owe property tax in the country where the property is located. This is a local obligation that exists regardless of your tax residency.

Where You Report Rental Income

Rental income is typically taxable in both the country where the property is located and your country of tax residency.

US taxpayers: If you are a US citizen or resident, you must report worldwide income including foreign rental income on your US tax return, regardless of where you live. You report foreign rental income on Schedule E and can claim a Foreign Tax Credit (Form 1116) for taxes paid to the foreign country to avoid double taxation. See IRS Publication 527 for the rules on residential rental property and IRS Publication 514 for Foreign Tax Credits.

UK taxpayers: HMRC requires you to report foreign rental income as part of your Self Assessment tax return. You can claim relief for foreign taxes paid under the terms of the relevant double taxation agreement. See HMRC’s guidance on foreign income.

For a detailed look at avoiding double taxation, see How to Avoid Double Taxation on International Investments.

Capital Gains When You Sell

Selling property abroad triggers capital gains tax considerations in multiple countries. The country where the property is located will almost always tax the gain. Your country of tax residency may also tax it, with relief available under a tax treaty.

US taxpayers: Foreign real estate gains are reported on Form 8949 and Schedule D. The gain must be calculated in USD using the exchange rate on the date of purchase (for cost basis) and the date of sale (for proceeds). This means that even if the property’s value was flat in local currency terms, you could have a taxable gain or loss due to exchange rate movement. See IRS Publication 544.

FBAR and FATCA Reporting

If you hold the proceeds from a foreign property sale in a foreign bank account, or if you receive rental income into a foreign account, those accounts may trigger US reporting requirements.

FBAR (FinCEN Form 114): Required if the aggregate value of your foreign financial accounts exceeds $10,000 at any point during the year. The property itself is not reportable, but the bank accounts holding rental income or sale proceeds are. See FinCEN’s FBAR filing page and our guide on How to File an FBAR as an Expat.

FATCA (Form 8938): Required for specified foreign financial assets exceeding $50,000 (higher thresholds for expats). Again, the property itself is excluded, but foreign accounts holding property-related funds are included.

Building Your Property Tracking System

A complete real estate tracking setup for international investors includes:

This does not need to be complicated, but it does need to be consistent. The biggest mistake in real estate tracking is doing it once and forgetting about it for two years. Quarterly updates take ten minutes and keep your net worth accurate.

Bringing It All Together

Real estate is an essential part of your net worth, and if you own property abroad, it needs to be tracked with the same rigor as your liquid investments. That means local currency valuation, home currency conversion, mortgage netting, and regular updates.

FlashFi lets you track property as part of your consolidated net worth alongside stocks, ETFs, crypto, cash, and debt — all converted to your home currency with live exchange rates. Add your property’s estimated value and mortgage balance, and see how it fits into your total financial picture.

Start tracking your complete net worth — including the real estate your other tools ignore.

By David Brougham