Tax treaty — meaning in cross-border tax

Rarely. A treaty allocates taxing rights rather than switching one country off. For many kinds of income it gives one country the primary right and leaves the other with a limited right, often a capped deduction at source, and then requires the residence country to relieve what the other took. So both countries can be involved, and the treaty's job is to stop the same income bearing full tax twice. A small number of income types are allocated exclusively, and those genuinely are taxable in one place only. Which category your income falls into depends on the article that covers it.

Both tax authorities publish the treaties they are party to, and that is the place to look rather than a secondary summary. Two cautions. A treaty may be signed without being in force, and the dates from which it applies can differ by type of tax, so read the entry-into-force and effective-date provisions rather than the signature date. And treaties are amended, sometimes by later agreements that change many treaties at once, so the copy you download is not necessarily the text that governed your year. Where money turns on it, the governing text for that specific year is what has to be read.

You have to characterise the income first, because the articles are organised by type and each sets its own rule. The same payment can look like more than one thing: a payment for the use of software, for instance, or a distribution that one country treats as a dividend and the other as something else. Characterisation follows the substance of the arrangement and the definitions in the treaty itself, which do not always match the label in the contract or in domestic law. Where two articles genuinely compete, most treaties have an ordering rule, and the position needs writing down before filing rather than arguing afterwards.

You claim them. A reduced rate at source generally depends on the payer holding documentation from you before it pays, and if it does not, the payer deducts at its domestic rate and is right to do so. Relief is then a matter of reclaiming, or of claiming on your return, which is slower and needs more evidence. Some benefits also depend on satisfying a test, of eligibility or of the purpose of the arrangement, so entitlement is not established simply by pointing at the article. Getting documentation to the payer before payment is the cheapest version of every treaty claim.

Treaties resolve this with a sequence of tests applied in order, not with a balance of factors. Each test is reached only if the one before it fails to settle the question, so the analysis stops at the first test that gives an answer, and arguments about later tests are irrelevant once it has. The tests turn on facts about your personal and economic life, which makes the work evidential: where your home is, where your life is centred, and what the records show. Both authorities can be expected to look at the same facts, so the file has to read the same way to each of them.

It can happen, and it is why the treaty text alone does not always settle a position. Domestic legislation can displace a treaty provision, and how far it can do so depends on that country's own constitutional arrangements, which differ. There is also a softer version of the same problem: a domestic rule that does not contradict the treaty but changes the outcome the treaty made available, for instance by re-characterising a payment before the treaty is applied. Either way, reading the treaty is half the exercise. The other half is what the domestic law of both countries did to it in your filing year.

It is the provision that lets each country keep taxing its own residents and citizens as though the treaty did not exist. Because the United States taxes on citizenship, the saving clause is what stops an American in Canada or India using the treaty to remove US tax on ordinary income. A short list of articles is carved out of it — certain pensions, social security, government service, students — and those exceptions are where a treaty position for a US citizen usually lives. See our treaty work.

For a resident, yes — worldwide gains are taxable, and the gain is computed in your own currency, so the exchange rate at purchase and at sale changes the number even when the local-currency price did not move. The country where the property sits usually taxes it too, often with a withholding or clearance step before closing, and that tax becomes a credit. A principal residence relief may apply to a home abroad on the same terms as one at home. See principal residence and foreign property.