Who actually needs to apply for Form 8802?
US persons and entities who have to prove US residency to someone outside the United States. The trigger is almost never on the US side: it is a foreign payer who will not apply a treaty rate without evidence, or a foreign tax authority that will not release a refund of tax already withheld. If nobody abroad is asking, there is nothing to apply for. If somebody is asking, the certification is the document they want, and the application is made before the payment or the refund claim rather than after it.
Do companies file Form 8802 or only individuals?
Both. Entities apply as well as individuals, and the point to get right is whose residency is being certified. The certification has to name the person the foreign payer is actually withholding from, which is not always the name on the contract or the invoice. Where income is routed through a structure, that question is answered before the application is drafted, because a certificate in the wrong name is refused abroad even though it was issued correctly. Working out who the foreign side sees as the recipient is the real first step.
Which year do I request the certification for?
The year the foreign income arises, and it must match. Asking for the current year when the payment fell in the previous one is the commonest reason a foreign authority rejects an otherwise good claim, and the rejection usually comes months later, by which time the treaty rate has gone and the money has been withheld. So the income year is pinned down first — from the payer's records if necessary — and the request is made for that year. If the arrangement runs over more than one year, more than one year is requested.
How far ahead of a foreign payment should I apply?
Earlier than most people expect. This is a lead-time problem rather than a technical one: the certification exists to be handed over before the foreign payer decides what rate to withhold, so the useful sequence is application, certificate, then payment. Once the payment has been made at the domestic rate, you have moved from applying a treaty rate to claiming a refund abroad, which is slower and depends on the foreign authority's own rules. Where there is a contract in place, the application is timed against the first invoice, not against the US filing season.
The foreign tax office wants its own form too — do I still need this?
Yes, and expect both. The two documents do different jobs. The certification is the US evidence that you are resident here for tax purposes; the foreign form is the claim you make under the treaty in that country, on that country's paperwork, in its language and to its timetable. Filers who supply only the certification are often told the claim was never made, and filers who supply only the local form are told the residency is unproven. Running the two together is what actually produces the reduced rate.
Do I need it if the payer already gave me the treaty rate?
Sometimes, and it is worth thinking ahead. A payer who applied the reduced rate without asking for evidence has taken a position that it may later be asked to support, and when that happens the request comes to you, often for a year that has long closed. Obtaining the certification while the year is current is much easier than reconstructing it afterwards. If the payer has asked for evidence, the answer is simpler: no certificate, no reduced rate.
Do I have to declare my dual citizenship?
A tax return does not generally ask you to declare which passports you hold; it asks about residence, and in the US case it applies to citizens by definition. What does ask is your bank. Account-opening self-certification under FATCA and the Common Reporting Standard asks which countries you are a tax resident or citizen of, and the answer is reported onward to the tax authority. So the practical answer is that the information arrives either way. See FATCA reporting.
What happens if two countries both say I am resident?
The treaty tie-breaker resolves it to one residence, applied in order: where your permanent home is, then your centre of vital interests, then your habitual abode, then nationality, with a competent-authority referral if all of those fail. It is an evidence exercise rather than an election — you document the home and the life around it. Getting a single residence settled is what makes every other position in both returns consistent. See the residency tie-breaker.
