Do I need to file a tax return as a student?
"In the U.S., Form 1040 is known as the tax return.  This is the form that is filed annually to calculate your tax due for the year, and you either claim a refund if you have overpaid your taxes or send in a payment if you have underpaid.  The form is generally due on April 15 each year, but this year the due date is April 18, 2016. When it comes to filing your taxes, there are two questions you need to ask yourself: ""Am I required to file?"" and ""Should I file?"" Am I required to file? The 1040 instructions has a section called ""Do I have to file?"" with several charts that determine if you are legally required to file.  It depends on your status and your gross income.  If you are single, under 65, and not a dependent on someone else's return, you are not required to file if your 2015 income was less than $10,300.  If you will be claimed as a dependent on someone else's return, however, you must file if your earned income (from work) was over $6300, or your unearned income (from investments) was over $1050, or your gross (total) income was more than the larger of either $1050 or your earned income + $350.  See the instructions for more details. Should I file? Even if you find that you are not required to file, it may be beneficial to you to file anyway.  There are two main reasons you might do this: If you have had income where tax has been taken out, you may have overpaid the tax.  Filing the tax return will allow you to get a refund of the amount that you overpaid. As a student, you may be eligible for student tax credits that can get you a refund even if you did not pay any tax during the year. How to file For low income tax payers, the IRS has a program called Free File that provides free filing software options." Should I go see a CPA? Not unless you are filing paperwork for a corporation.  A CPA (Certified Public Accountant) is a certification required to file certain paperwork for a corporation.  In any other situation, you don't need a CPA and can just use a regular accountant.   You could conceivably go to a tax accountant, but unless you are doing something complicated (like your own business) or are rich enough that everything is complicated, you should not need to do so.
Any large stockbroker will offer trading in US securities. As a foreign national you will be required to register with the US tax authorities (IRS) by completing and filing a W-8BEN form and pay US withholding taxes on any dividend income you receive.  US dividends are paid net of withholding taxes, so you do not need to file a US tax return.  Capital gains are not subject to US taxes.  Also, each year you are holding US securities, you will receive a form from the IRS which you are required to complete and return. You will also be required to complete and file forms for each of the exchanges you wish to received market price data from. Trading will be restricted to US trading hours, which I believe is 6 hours ahead of Denmark for the New York markets.  You will simply submit an order to the desired market using your broker's online trading software or your broker's telephone dealing service. You can expect to pay significantly higher commissions for trading US securities when compared to domestic securities. You will also face potentially large foreign exchange fees when exchaning your funds from EUR to USD. All in all, you will probably be better off using your local market to trade US index or sector ETFs. "1099's and other official tax forms are often reported to the IRS by the issuer, whether or not you include a copy in your return. You should not neglect to include this income in your 2016 return in an attempt to balance out the two tax years. It's up to you whether or not you feel like filing an amended 2015 return to recover over-payment of taxes from that tax year. You have up to three years to amend tax returns using form 1040X. Since you couldn't have furnished a 1099 for this when you filed your 2015 return (otherwise you wouldn't be in receipt of it for tax year 2016), I'm assuming you reported it simply as ""Other Income"" and therefore would have been [over] taxed your marginal rate on it. From irs.gov: When to amend a return.  You should file an amended return if you need to correct your filing status, number of dependents, total income, tax deductions or tax credits. The instructions for Form 1040X, Amended U.S. Individual Income Tax Return, list additional reasons to amend a return." There are penalties for failure to file and penalties for failure to pay tax.  The penalties for both are based on the amount of tax due.  So you would owe % penalties of zero, otherwise meaning no penalties at all. The IRS on late 1040 penalties: Here are eight important points about penalties for filing or paying late. A failure-to-file penalty may apply if you did not file by the tax filing deadline. A failure-to-pay penalty may apply if you did not pay all of the taxes you owe by the tax filing deadline. The failure-to-file penalty is generally more than the failure-to-pay penalty. You should file your tax return on time each year, even if you’re not able to pay all the taxes you owe by the due date. You can reduce additional interest and penalties by paying as much as you can with your tax return. You should  explore other payment options such as getting a loan or making an installment agreement to make payments. The IRS will work with you. The penalty for filing late is normally 5 percent of the unpaid taxes for each month or part of a month that a tax return is late. That penalty starts accruing the day after the tax filing due date and will not exceed 25 percent of your unpaid taxes. If you do not pay your taxes by the tax deadline, you normally will face a failure-to-pay penalty of ½ of 1 percent of your unpaid taxes. That penalty applies for each month or part of a month after the due date and starts accruing the day after the tax-filing due date. If you timely requested an extension of time to file your individual income tax return and paid at least 90 percent of the taxes you owe with your request, you may not face a failure-to-pay penalty. However, you must pay any remaining balance by the extended due date. If both the 5 percent failure-to-file penalty and the ½ percent failure-to-pay penalties apply in any month, the maximum penalty that you’ll pay for both is 5 percent. If you file your return more than 60 days after the due date or extended due date, the minimum penalty is the smaller of $135 or 100 percent of the unpaid tax. You will not have to pay a late-filing or late-payment penalty if you can show reasonable cause for not filing or paying on time. If the IRS owes you a refund, April 15 isn't much of a deadline. I suppose the real deadline is April 15, three years later - that's when the IRS keeps your refund and it becomes property of the Treasury.  Of course, there's little reason to wait that long.  Don't let the Treasury get all your interest. The obligation is contractual, so you need to read the contract to answer your question. However, since you paid for the service provided, I see no way they can force you buy any other service from them. They cannot file your tax returns without your explicit consent (on a form dedicated to that, dated and having the numbers matching the return filed - not something you can sign before the actual return is ready). Worst case they can claim you owe them more money, but since you paid for the services provided, I can't see how they can have that stand in court as well. Bottom line - even if the contract has such an obligation, I cannot see how it can be enforced. As to the mistake they noted... I wouldn't rely on H&R Block advice in any matter. Very likely, the person you were talking to was not even licensed to provide tax advice. You're lucky if the person has passed CRTP exams (in California they're legally required), but I seriously doubt their clerks are EAs or CPAs (the only designations other than a lawyer legally allowed to provide tax advice). Tax preparers (CRTPs included) are only allowed to provide advice pertaining to the preparation of the tax return they're currently engaged to prepare. Claiming income is sourced or not sourced in NY is borderline, IMHO. If they got it wrong (and to me it sounds as they did) you can sue them for damages. If your situation is tricky and it is too late to get an appointment with a proper adviser - file an extension (form 4868) and deal with it after the April busy season. It is unlikely that UK tax will be due on the money -- see here: Foreign students usually don’t pay UK tax on foreign income or gains, as long as they’re used for course fees or living costs But if the UK doesn't tax you on the money then double-taxation agreements probably won't apply, and so any Italian tax due will be payable. First - get a professional tax consultation with a NY-licensed CPA or EA. At what point do I need to worry about collecting sales taxes for the city and state of New York? Generally, from the beginning. See here for more information on NYS sales tax.  At what point do I need to worry about record-keeping to report the income on my own taxes? From the beginning. Even before that, since you need the records to calculate the costs of production and expenses. I suggest starting recording everything, as soon as possible. What sort of business structures should I research if I want to   formalize this as less of a hobby and more of a business? You don't have to have a business structure, you can do it as a sole proprietor. If you're doing it for-profit - I suggest treating it as a business, and reporting it on your taxes as a business (Schedule C), so that you could deduct the initial losses. But the tax authorities don't like business that keep losing money, so if you're not expecting any profit in the next 3-4 years - keep it reported as a hobby (Misc income). Talk to a licensed tax professional about the differences in tax treatment and reporting. You will still be taxed on your income, and will still be liable for sales tax, whether you treat it as a hobby or as a business. Official business (for-profit activity) will require additional licenses and fees, hobby (not-for-profit activity) might not. Check with the local authorities (city/county/State). From the IRS web site: So if your income was reported to the IRS (by the payer, not you) using one of the forms above, the IRS would have a record of it, regardless of whether you filed a tax return or not. Since you were a nonresident alien student on F-1 visa then you will be considered engaged in a trade or business in the USA. You must file Form 1040NR.  Here is the detailed instruction by IRS - http://www.irs.gov/Individuals/International-Taxpayers/Taxation-of-Nonresident-Aliens