What is an advance ruling in tax?
An advance ruling is a determination of how a tax authority will treat a transaction you have not yet carried out. You set out the proposed steps, the facts behind them and the treatment you say follows, and the authority rules on that treatment. The ruling binds the authority to the position it states, provided the transaction is completed as described. That is the whole value of it: certainty obtained before the money moves, rather than an argument after an assessment arrives. It is not advice and it is not a negotiation. The authority rules on the facts you present, so the application is largely an exercise in describing a transaction precisely.
Can I apply for a ruling after signing the contract?
A ruling is for a proposed transaction, so timing decides whether the route is open at all. Once the steps have been carried out there is nothing left to rule on, and the question becomes an assessment or an objection instead. A signed agreement is not automatically fatal: what matters is whether the transaction it provides for has actually happened. An agreement made conditional on the ruling itself is common and is usually the right way to sequence a deal. Where the transaction has already completed, ask instead whether a disclosure or a technical interpretation is the appropriate route, and expect no binding comfort from either.
Is an advance ruling binding on the tax authority?
Yes, within limits worth understanding before you rely on one. The ruling binds the authority to the treatment it states, for the transaction it describes, in the hands of the taxpayer who applied. It does not bind the authority for a different taxpayer, for a period outside its stated scope, or for a transaction that differs from the one described. It also does not bind the tax authority of the other country, which is the trap in a cross-border file: a ruling secures one side of the position and leaves the other side to be argued on that country's own rules.
What if the transaction changes after the ruling is issued?
Then the ruling may not cover what you did. A ruling attaches to the facts in the application, and a step inserted, dropped or reordered can put the completed transaction outside its terms. The authority is entitled to say so, and you are back to arguing the treatment on its merits holding a document that looks like comfort but is not. The practical discipline is to compare the executed steps against the application before the return is filed, and to decide deliberately whether to seek a further ruling, amend the application while the transaction is still proposed, or disclose the difference.
Do I have to disclose all the facts in the application?
Yes, and the completeness of the disclosure is what makes the ruling worth having. A ruling given on incomplete or inaccurate facts can be treated as not applying, so a fact withheld to improve the answer destroys the only thing you were buying. That includes the commercial purpose, related arrangements in the other country, and anything you would rather the authority did not weigh. Where a fact is genuinely unhelpful, the honest options are to change the transaction, accept the treatment, or not apply. Describing a transaction that is not the one you intend to carry out is not among them.
Is an advance ruling published or kept confidential?
Rulings are commonly published in edited form, with the applicant's identifying details removed. The published version is useful reading, because it shows how the authority reasons on a fact pattern, but it is not comfort you can rely on: it is somebody else's transaction and the facts that mattered may not be the facts reported. Treat published rulings as an indication of the authority's thinking when deciding whether to apply, and treat your own ruling as the only one that binds anything. If confidentiality is a live concern for a transaction, raise it in the application rather than after issue.
How would a foreign tax authority know I am resident there?
Mostly from information you or your bank already provided. Account-opening forms ask you to self-certify tax residence, and that certification is reported between authorities under the Common Reporting Standard or, for US accounts, under the FATCA framework. Beyond that: employer and payroll filings, property registries, immigration records and the tax filings of anyone who paid you. The realistic planning assumption is that the data arrives. See FATCA and information reporting.
How does the treaty tie-breaker work when both countries say I am resident?
As a sequence, stopping at the first test that gives an answer: where you have a permanent home available; if in both or neither, where your centre of vital interests is; then habitual abode; then nationality; and if all of those tie, the two tax authorities decide by agreement. It is evidential rather than elective — you do not choose your treaty residence, you demonstrate it, which makes the record of homes, family and time the substance of the claim. See tie-breaking dual residency.
