Section 1202 is an exclusion from US federal income tax. It can only help you if you owe US federal income tax on the gain in the first place, and if you’re not a US taxpayer, you usually don’t. For most non-US angels investing in American startups, QSBS is a rule that applies to their co-investors and not to them. The QSBS calculator has an option for exactly this case, and it mostly reports that there’s nothing to exclude.
Non-resident aliens generally owe no US tax on the gain
A non-resident alien, meaning someone who is neither a US citizen nor a US tax resident, generally isn’t subject to US tax on the gain from selling stock in a US company. Two exceptions: gain that’s effectively connected with a US trade or business you conduct, and the rule that taxes capital gains of a non-resident who was physically present in the US for 183 days or more in the year of sale. Outside those, there’s no US tax for Section 1202 to remove.
That means your home country’s rules govern, along with any tax treaty it has with the US. Most treaties give the taxing right on share sales to the country of residence. The UK, Canada, Germany, Australia, and most other countries tax their residents on worldwide capital gains, and none of them recognizes Section 1202. Some have their own incentives with a family resemblance: the UK’s EIS and SEIS reliefs, or Canada’s lifetime exemption for “qualified small business corporation” shares, which despite the near-identical name is a different rule with different tests that a US startup won’t meet.
US citizens and green card holders abroad
You’re still a US taxpayer wherever you live, and Section 1202 applies to you normally. You’ll typically owe tax where you live as well, and whether that country gives you a credit for US tax on the gain (or the US gives you one for theirs) is a treaty question. Note that an exclusion produces no US tax to credit, so a fully excluded federal gain can still be fully taxed abroad, much as it is in California.
If you become a US taxpayer while holding
Nothing in Section 1202 requires you to have been a US taxpayer when the stock was issued. Whether the stock is QSBS depends on the company and the issuance: a US C corporation, under the gross-assets ceiling at issuance, shares acquired by you at original issuance. If those held when you invested, the holding period counts from the original acquisition date, not from the day you moved. Someone who invested from London in 2023 and became a California resident in 2026 may well hold QSBS, with a clock that’s already three years along.
The company has to be American
The rule that trips up non-US angels most often runs the other direction. Section 1202 requires a domestic C corporation. A Delaware C-corp founded by non-US founders qualifies; a UK Ltd, an Estonian OÜ, or a Singapore Pte. Ltd. does not, no matter where the investor lives. If you’re a US taxpayer investing internationally, none of those positions are QSBS. If a foreign startup later flips into a Delaware parent, the stock you receive in the flip may or may not qualify, and the answer depends on the details of the exchange. This is general information, not tax advice.