How to Calculate Tax on Income From Multiple Countries

A client in one country. A platform based in another. Tax withheld by a third before the money reached you. And one tax return at home that is supposed to account for all of it.

This is ordinary now for freelancers, creators and online sellers, and calculating tax on income from multiple countries is less mysterious than it looks. The rates differ from country to country and change from year to year. The method does not. This page sets out the method, in six steps, with a worked example using made-up countries and rates, so none of it depends on figures that will be out of date by next year.

For your own return, the rates come from your country's tax authority, and a qualified adviser should check the result. What follows is the structure they will use.

Step 1: Work out where you are tax resident

Everything starts here. Residency, not citizenship and not where the platform is based, decides which country taxes you on your total income.

Most countries that tax residents do so on their worldwide income: everything you earn, wherever it comes from, whether or not it ever reaches a bank account at home. A smaller number tax mainly what is earned inside their borders. Which kind your country is decides how much of the rest of this page applies to you.

If two countries could both treat you as resident, a tax treaty between them usually settles it. The OECD Model Tax Convention, which most treaties follow, sets out tie-breaker tests in Article 4: where you have a permanent home, where your personal and economic ties are strongest, where you habitually live, and your nationality. Platform tax basics covers residency in more depth.

Step 2: List every income stream at its gross amount

For each stream, record what the client, customer or platform paid you before any fee or tax came off. Not what reached your account.

That matters twice over here. Fees are a cost you can usually deduct, and tax withheld abroad is a payment you can usually claim back through a credit. Record only the deposit and you lose both.

Step 3: Note where each stream came from, and what was withheld

Some countries take tax at source before paying a foreign earner. A client's country may withhold tax from an invoice. A platform may withhold tax on earnings from viewers or customers in its home country: YouTube, for example, can withhold US tax from non-US creators on earnings from US viewers, and reports it on a US tax form (Form 1042-S).

Online sellers usually see less withholding on sales, but the same record applies to any marketplace or payment processor that deducts tax before paying you.

For each stream, record the country it came from, the tax withheld, and the document that proves it: a withholding certificate, a tax form from the platform, or a payment statement showing the deduction. Without that document, the credit in Step 5 is hard to claim.

Step 4: Convert everything into your home currency, on one basis

Your return is in one currency. Your income is not. Convert every payment, and every amount of tax withheld, into your home currency.

The income is fixed on the day it landed, or in some countries the day it was earned, not the day you converted it. So value each payment at a reputable published rate for that date, from the same source every time, and keep the evidence. Converting the money later, or never converting it, does not change the income. It creates a separate exchange gain or loss, which several countries tax in its own right, so record the conversion too: when, at what rate, and what you received.

A few countries set the date or rate themselves. Canada, for example, counts self-employed income on the date it was earned, and India converts business income held abroad at the rate on 31 March. Your adviser will know your country's rule; the record above works for all of them. Getting paid in several currencies covers what conversion costs along the way.

Step 5: Work out your home tax on the total

Add up the gross income from every stream, take off your deductible costs, and apply your home country's rates to the result. This is the tax you would owe if all of it had been earned at home.

Step 6: Take off the tax already paid abroad

This is the step that stops the same income being taxed twice, known as double taxation relief. A foreign tax credit is a reduction in your home tax for tax you have already paid to another country on the same income. Treaties generally give relief in one of two ways, set out in Articles 23A and 23B of the OECD Model Tax Convention:

• Credit: you include the foreign income at home, then subtract the tax already paid abroad. The credit is usually capped at your home tax on that same income.
• Exemption: the income taxed abroad is left out of your home tax. Some countries still count it when deciding which rate applies to the rest of your income.

Which method applies depends on your home country and the treaty in question. Where there is no treaty, some countries still give a credit under their own rules, and others do not.

Worked example: tax on income from three countries

The countries and rates below are invented, to show the method. Everything is already converted into your home currency at the rates you recorded, and your home country is assumed to tax income at a flat 25% to keep the arithmetic simple. Real systems use bands.

Home tax on the total: 25% of 40,000 = 10,000.

Foreign tax credit: your home tax on the Country A income would be 2,500, and Country A took 1,000, so the full 1,000 is credited. On the Country B income your home tax would be 1,500, and Country B took 900, so the full 900 is credited. For simplicity, the costs here all relate to your work at home.

Left to pay at home: 10,000 − 1,900 = 8,100.

In total you pay 10,000: 8,100 at home and 1,900 abroad. That is the same as if all of it had been earned at home. When the foreign rates are lower than your home rate, the credit makes the total come out even.

The two mistakes that make people pay twice

Declaring what landed instead of the gross. Suppose, in the example above, you declared only what reached you from Countries A and B: 9,000 and 5,100. Your taxable profit becomes 38,100 and your home tax 9,525, but you have claimed no credit, because on paper there was no foreign tax. Add the 1,900 already taken abroad and you have paid 11,425 in total: 1,425 more than you owed, on a return that also understates your income.

Assuming every foreign tax is creditable in full. Suppose Country C withholds 30% on 4,000 of income: 1,200. Your home tax on that income would be 1,000, so the credit is capped at 1,000. The other 200 is not credited at home. If a treaty sets a lower withholding rate than Country C applied, that 200 is normally recovered from Country C, usually by giving the payer the right form before you are paid, or by claiming a refund from Country C afterwards. Your home country will not refund it.

Three things this method does not cover

• Social security contributions. These are usually separate from income tax, and income tax treaties generally do not cover them. Some countries have separate social security agreements.
• Tax years that do not line up. Not every country's tax year runs from January to December, so a payment can fall in one tax year abroad and a different one at home. Record the payment date, and the credit can be matched to the right year.
• Sales taxes on what you sell abroad. VAT, GST and sales tax on digital products or goods sold to customers in other countries are a separate system from income tax, with their own registration rules. The six steps above cover income tax only.
• Local filing obligations abroad. Having tax withheld does not always end your obligations in that country. Some expect a return, particularly if you work there in person.

What to keep

For every foreign payment: the gross amount, the currency, the date it landed, the published rate for that date and its source, the tax withheld, and the document that proves the withholding. When you convert the money, add the date, the rate you got and what you received. That is what an accountant needs to claim a credit, and what you need if the figures are ever questioned. The record-keeping system that works sets out how to keep it without it taking over your week.

If your income arrives from several platforms and several countries, the hard part is rarely the calculation. It is having every gross figure, every currency and every withholding in one place when the calculation is due. That is what the income tracker is built for: gross, fees and net held as separate figures for every platform and currency, in one total. For what applies where you live, including whether PlatformTaxHub estimates tax for your country, check the countries page. If the same income has already been taxed twice, the double taxation trap sets out how that happens and how it is usually put right.