I forgot to report a foreign bank account — do I amend or disclose?
Not automatically an amendment. Form 1040-X corrects a filed position; it does not, by itself, carry the protection a disclosure procedure carries. Where the original return left out foreign income or foreign accounts, the route is chosen before anything is typed, because a quiet correction can forfeit relief that was otherwise on the table and cannot be undone afterwards. We look at what was omitted, over which years, and how it came to be omitted, and the answer to that last question is usually what decides the route. What a quiet amendment costs sets out what is given up.
Do I file Form 1040-X if the IRS already corrected my return?
Usually not. Where the IRS adjusts arithmetic or a clerical entry itself, it writes and tells you what it changed, and the year stands as adjusted; the response there is to check the adjustment against your own figures. Form 1040-X is for a change to the position you filed — income left out, a residency status that was wrong, an election, a credit or an exclusion that was missed. If the notice and your own correction point in different directions, reconcile them before either goes in, or you end up arguing two versions of one year. See responding to an IRS notice.
Can I amend a 1040-NR the same way as a 1040?
Yes, the same form amends both, and it has to say which return is being amended. The complication is not the mechanics but the status underneath them. A year split between non-residence and residence is filed in a particular shape, and an amendment that changes the income without changing the status leaves the return internally inconsistent. So the first question is whether the original status was right. If it was, the amendment is arithmetic and evidence. If it was not, it is a residency case with a return attached, and the income figures follow from the answer rather than the other way round. More on the non-resident return.
Can I claim a foreign tax credit I missed on a filed return?
Yes, by amending, and the sooner it is done the better: a refund claim carries a limitation period of its own, and an amendment filed after it closes does not recover the overpayment however plainly right it is. The credit is also computed for each category of income separately, so an unclaimed credit does not simply come off the bill — it has to be worked through in the category it belongs to, and what cannot be used there carries rather than disappearing. That carry is why correcting one year almost always changes the years after it. See the foreign tax credit.
Does amending one year mean amending the other years as well?
Often, and in two directions. Forward: a figure you change — a carried credit, a loss, a cost base — is an input to the years that follow, so leaving those alone publishes two inconsistent versions of the same history. Sideways: where another country gave relief computed from the numbers being changed here, that relief now rests on figures that no longer exist, and the filing there has to move with it. The scope is settled before anything goes in, because filing one year and finding the rest afterwards is how a small correction becomes a long project. See amending across countries.
I missed an information form but no income — do I still amend?
It depends where the form belongs. A statement that attaches to the return, such as Form 8938, was part of what you filed, so putting it right means amending the return it should have travelled with. An account report filed separately with the Treasury's financial-crimes bureau, such as the FBAR, is not part of the return at all; it is corrected on its own track, and amending the tax return does not reach it. Most cross-border filers who missed one turn out to have missed both, which is why the two are scoped together rather than in sequence. See filing both.
Do I have to file in both countries?
Frequently yes, and the two filings do different jobs. The country where the income arises taxes it at source; the country where you are resident taxes your worldwide income and then gives credit for the tax already paid. Filing only one side is what leaves relief unclaimed — the credit has to be asked for on a return. We prepare both sides so the numbers agree. See dual filing.
Is double taxation illegal?
It is legal. Two countries can each have a valid claim on the same income — one because the income arose there, the other because you live there — and nothing prohibits both from exercising it. What exists instead is relief: tax treaties allocate the claim, and domestic law gives a credit for foreign tax paid. The relief is not automatic, though. It is claimed on a return, and unclaimed relief is simply lost. See how double taxation is relieved.
