Federal taxes for nonresident alien whose only income in 2016 was a 2015 state tax return
"I believe you have to file a tax return, because state tax refund is considered income effectively connected with US trade or business, and the 1040NR instructions section ""Who Must File"" includes people who were engaged in trade or business in the US and had a gross income. You won't end up having to pay any taxes as the income is less than your personal exemption of $4050."
Having a large state return also means that there is a potential income tax liability created at the federal level for the following year, as the situation resulted from the deduction of more on one's federal return than should have been deducted. The state refund is treated as federal income in the year it is refunded. http://blog.turbotax.intuit.com/tax-tips/is-my-state-tax-refund-taxable-and-why-90/ You can't change the W2, the employer issues it and sends it to the IRS. You cannot affect it in any way. The employer reported correctly. You did contribute $4137 in 2015. You then withdrew the excess in 2016, and did it timely, so it is not taxable in 2016. However, the excess contribution should be added back to your wages on your tax return. The way to do it is to add it to the taxable wages amount (reported on W2 box 1), and attach a statement explaining that the amount added is the excess contribution. You then put the corrected amount in the right place on your tax return (line 7 on the form 1040). Adding the difference to misc income (line 21) is OK too, it's the same effect. You will then need to check with your payroll that they're aware that the excess was deposited back on the account of the next year and adjust their reports accordingly. Otherwise you'll end up with excess contribution again. You're interpreting this correctly. Furthermore, if your total tax liability is less than $1000, you can not pay estimates at all, just pay at the tax day. See this safe harbor rule in the IRS publication 17: General rule.    In most cases, you must pay estimated tax for 2016 if   both of the following apply. You expect to owe at least $1,000 in tax for 2016, after subtracting your withholding and refundable credits. You expect your withholding plus your refundable credits to be less than the smaller of: 90% of the tax to be shown on your 2016 tax return, or 100% of the tax shown on your 2015 tax return (but see Special rules for farmers, fishermen, and higher income taxpayers , later).   Your 2015 tax return must cover all 12 months. "So, if I understand the investment program here: You have $100 of tax withheld from your salary at the end of Jan, Feb, Mar... until December.  This withholding is in excess of the expected tax for the year. You use the appropriate H&R Block product to file your taxes, and H&R Block gets your refund of $1200 on March 1st.  H&R Block adds 10& and give you e-cards for $1320 On the face of it, this represents a return of 15.19% per year, compounded monthly. However, there are a few wrinkles that might make the scheme less inviting: You'll get a receipt for miscellaneous income from H&R Block, and pay tax on the ""earnings"". The quoted return is only realized if you can use the e-cards immediately.  If they sit around for a while, then they aren't earning any interest.  If you sell them for cash at a discount (if you even can!)  then this reduces the return.  If you don't cash them at all, they're a total loss. This offer was announced on Jan 15, 2015.  So you can't go back and put it in place for 2014.  And if you set it up for withholding in 2015, is there any guarantee that it the same offer will be in place when filing in 2016?" They are four quarterly estimated tax payments.   The IRS requires that you pay your taxes throughout the year (withholding in a W-2 job).  You'll need to estimate how much taxes you think you might be owing and then pay roughly 1/4 at each of the 4 deadlines. From the IRS: How To Figure Estimated Tax To figure your estimated tax, you must   figure your expected AGI, taxable   income, taxes, deductions, and credits   for the year. When figuring your 2011 estimated tax,   it may be helpful to use your income,   deductions, and credits for 2010 as a   starting point. Use your 2010 federal   tax return as a guide. You can use   Form 1040-ES to figure your estimated   tax. Nonresident aliens use Form   1040-ES (NR) to figure estimated tax. You must make adjustments both for   changes in your own situation and for   recent changes in the tax law. For   2011, there are several changes in the   law. Some of these changes are   discussed under What's New for 2011   beginning on page 2. For information   about these and other changes in the   law, visit the IRS website at IRS.gov. The instructions for Form 1040-ES   include a worksheet to help you figure   your estimated tax. Keep the worksheet   for your records. You may find some value from hiring a CPA to help you setup your estimated tax payments and amounts. "I have an indirect answer for you. It is not a numeric answer but it is a procedure. The challenge with paying taxes for an employee besides their share of Social security and Medicare is that you have no idea what their state and Federal taxes are.  Are they married, single, head of household? Is this their entire families income, or is it  extra money to make ends meet? What about state taxes?  It looks like you will need a W-4 from them.  As you know the IRS Tax topic 756 has all the info you need. Federal Income Tax Withholding You are not required to withhold federal income tax from wages you pay   to a household employee. However, if your employee asks you to   withhold federal income tax and you agree, you will need a completed   Form W-4 (PDF), Employee's Withholding Allowance Certificate from your   employee. See Publication 15, (Circular E), Employer's Tax Guide,   which has tax withholding tables that are updated each year.  Form W-2, Wage and Tax Statement If you must withhold and pay Social Security and Medicare taxes, or if   you withhold federal income tax, you will need to complete Form W-2   (PDF), Wage and Tax Statement, for each employee. You will also need a   Form W-3 (PDF), Transmittal of Wage and Tax Statement. See ""What Forms   Must You File?"" in Publication 926 (PDF) for information on when and   where to furnish and file these forms. To complete Form W-2 you will   need an employer identification number (EIN) and your employees'   Social Security numbers. If you do not already have an EIN, you can   apply for one using the online EIN application available on IRS.gov.   This service is available Monday through Friday, 7 a.m. to 10 p.m.   Eastern time. You can also apply for an EIN by mailing or faxing a   completed Form SS-4 (PDF), Application for Employer Identification   Number. International applicants may apply by calling 267-941-1099   (not a toll-free number) Monday through Friday, 6 a.m. to 11 p.m.   Eastern time to obtain their EIN. Refer to Topics 752 and 755 for   further information. Don't forget Federal Unemployment Tax. Pub 15 will have tables so you can determine how much you should have been withholding if you had gone that route. It will be easiest to use a spreadsheet to do the calculations so that what you gave them in their checks is their net pay not their gross. The tables are constructed under the assumption you know their gross pay." IANAL, I am married to someone in your situation. As a US citizen age 26 who has not had any contact with the IRS, you should most definitely be worried... As a US citizen, you are (and always have been) required to file a US tax return and pay any tax on all income, no matter where earned, and no matter where you reside.  There are often (but not always) agreements between governments to reduce double taxation.  The US rule as to whether a particular type of income is taxable will prevail. As a US citizen with financial accounts (chequing, saving, investment, etc.) above a minimum balance, abroad, you are required to report information, including the amounts in the account, to the US government annually (Look up FBAR).  Failure to file these forms carries harsh penalties. A recent law (FATCA) requires foreign financial institutions to report information on their US citizen clients to the US, irrespective of any local banking privacy laws.  It's possible that your application triggered these reporting requirements. You will not be allowed to renounce your US citizenship until you have paid all past US taxes and penalties. Good new:  you are eligible in ten years or so to run for President. Don't believe any of this, or that nothing has been missed; you must consult with a local tax expert specializing in US/UK tax laws. Unfortunately, you are required, but most states do have agreements with neighboring states that let the states share the collected taxes without the person having to pay double taxes. So being as this is your first tax return in your current situation, you might be wise to have a professional fill it out for you this year and then next year you can use it as a template. Additionally, I really would like to see someone challenge this across state lines taxation in court. It sure seems to me that it is a inter-state tariff/duty, which the state's are expressly forbidden from doing in the constitution.