W-4 and withholding taxes for self-employed spouse
"Littleadv is incorrect because receiving a 1099 means she will be taxed self-employment tax on top of federal income taxes. Your employer will automatically withhold 7.65% of payroll taxes as they pay you each paycheck and then they'll automatically pay the other half of your payroll tax (an additional 7.65%) to bring it to a total of 15.3%. In other words, because your wife is technically self employed, she will owe both sides of payroll tax which is 15.3% of $38k = $5,800 on TOP of your federal income tax (which is the only thing the W-4 is instructing them about what amount to withhold). The huge advantage to a 1099, however, is that she's essentially self-employed which means ALL of the things she needs to run her business are deductible expenses. This includes her car, computer, home office, supplies, sometimes phone, gas, maintenance, travel expenses, sometimes entertainment, etc - which can easily bring her ""income"" down from $38k to lets say $23k, reducing both her federal income tax AND self-employment tax to apply to $15k less (saving lets say 50% of $15k = $7.5k with federal and self employment because your income is so high). She is actually supposed to pay quarterly taxes to make up for all of this. The easy way to do this is each quarter plug YOUR total salary + bonus and the tax YOU have paid so far (check your paystubs) into TurboTax along with her income so far and all of her expenses. This will give you how much tax you can expect to have left to owe so far--this would be your first quarter. When you calculate your other quarters, do it the exact same way and just subtract what you've already paid so far that year from your total tax liability." With your income so high, your marginal tax rate should be pretty easy to determine.  You are very likely in the 33% tax bracket (married filing jointly income range of $231,450 to $413,350), so your wife's additional income will effectively be taxed at 33% plus 15% for self-employment taxes. Rounding to 50% means you need to withhold $19,000 over the year (or slightly less depending on what business expenses you can deduct). You could use a similar calculation for CA state taxes. You can either just add this gross additional amount to your withholdings, or make an estimated tax payment every quarter.  Any difference will be made up when you file your 2017 taxes. So long as you withhold 100% of your total tax liability from last year, you should not have any underpayment penalties. When you enter your expected gross income into the worksheet - just enter $360000 and leave everything else as is. That should give you the right numbers. Same for State (form DE-4).
"Look at how much tax you paid last year, including withholding and any additional amount that might have been due with the tax return. Look at the instructions for the W-4 form, which sets how much tax you want your employer to withhold. Adjust the numbers on that form until the total withheld during the year is close to what you expect this year's total to be -- remember, though, that there's no penalty for over-withholding but could be for under-withholding. Submit the W-4 form to your employer.  Remember that we're a few weeks into the year, so even if you adjust withholding now there will have been several paychecks at the prior setting; you can try to build that into your guesstimate of how to reset the withholding, or just not worry about it. Do the same with your state's withholding adjustments form. Repeat on a yearly basis, to account for raises, changes in other income, changes in filing status, etc. until it's close enough that you're satisfied with it. Then reconsider if/when your financial situation changes. Personally I find that exercise more effort than it's worth, and have simply set my withholding at ""close enough"". I usually get some money back from the feds and owe some to the state, but either is handled happily by my normal bank account balance." Should I have a W-2 re-issued? A W-2 can be corrected and a new copy will be filed with the IRS if your employer incorrectly reported your income and withholding on a W-2 that they issued. In this case, though the employer didn't withhold those taxes, they should not reissue the W-2 unless they plan to pay your portion of the payroll taxes that were not withheld. (If they paid your share of the taxes, that would increase your gross income.) Who pays for the FICA I should have paid last year? Both you and your employer owe 7.65% each for FICA taxes. By law your employer is required to pay their half and you are required to pay your half. Both you and your employer owe additional taxes because of this mistake. Your other questions assume that your employer will pay your portion of the taxes withheld. You employer could decide to do that, but this also assumes that it was your employer's fault that the mistakes were made. If you transitioned to resident alien but did not inform your employer, how is that your employer's fault? For 2014/15 it looks something like this:  To make it a bit clearer, let's also plot the difference in net income for self-employment and a single person company compared to employment:  Self-employment is slightly worse between £5885 and about £10,500 because Class 2 NI kicks in before the employed person starts paying any tax. After that, self-employment is better because you pay 9% Class 4 NI rather than 12% Class 1 NI. Once higher rate tax kicks in, the saving stops growing. The single-person company is most tax-efficient at all points, ignoring any accountancy costs it incurs. Strange things happen between £100k and about £135k because the withdrawal of the personal allowance kicks in at a different point when receiving dividends. We can also plot the percentage of income paid as tax for each case:  The strange kink for self-employment below £10k is caused by Class 2 NI again. Employment and self-employment both gradually tend towards paying 47%, reaching 46.5% for £2m gross income. The company tends towards 44.44%, reaching 43.6% for £2m gross income. As @littleadv's comment on your question said, it is unlikely that you and your husband paid a total of $5K in income tax on $185K of wages in 2013. More likely, your 2013 tax return (assumed to be a Married Filing Jointly tax return) showed that you had not arranged to have  enough tax withheld from your salaries and thus you still owed $5K  to the IRS for 2013 taxes. Most likely, that $5K sum included not just the unpaid amount of tax but also  penalties for not paying enough income tax during 2013 and interest on the amounts not paid on time.  Just to be clear, note that the income tax you paid for 2013 during 2013 is the total of all income tax withheld from your wages by your employers (plus any estimated tax payments that you might have made for 2013). If your 2014 tax return (that you will be filing by April 15, 2015)  will likely show a similar amount due for 2014 taxes, you can avoid  the penalties and interest by increasing  your income tax withholding by a substantial amount for the remainder of 2014. If you are paid monthly and have two paychecks still to be received, then having $2500 extra withheld from each paycheck will cover the $5K shortfall that you expect to have for 2014 taxes. I assume that this is what your husband intended you to do, and to do  this, you need to fill out a new W-4 Form (asking that an addiitonal  $2500 be withheld from each paycheck) and give this form to your employer soon (i.e. well before Payroll processes your next paycheck which usually happens a few days before you get the paycheck).  If you do so, your take-home pay will be reduced by $2500 on each of the next two monthly paychecks because your employer will withhold this extra amount from your pay and include it in the amount sent to the IRS as income tax withheld from your paycheck. After your last paycheck for 2014 has been received, you should submit a new W-4 Form to your asking for only $417 in extra income tax to be withheld from each paycheck starting January 1, 2015, so that  the expected $5K shortfall for 2015 is paid in 12 equal monthly installments. If you neglect to do this, your employer will continue to withhold $2500 extra as income tax, and you will get $2500 less in take-home pay month after month in 2015. This money will not disappear forever; come 2016 when you file your income tax return for 2015, you will receive a substantial refund because you overpaid income tax by a lot during 2015. You will not, however, receive any interest on the amount that the IRS is returning to you unless the IRS delays in sending you the refund for some reason.  Alternatively, you can file a new W-4 asking for no additional tax to be withheld from 2015 paychecks, and a year from now, go through the same exercise as above: have $2500 extra withheld from the last two paychecks for 2015, right when the holidays are coming and people are shopping for gifts. Can I work on 1099 from my own company instead of on W2? The reason is   on W2 I can't deduct my commute, Health Insurance and some other   expenses while on 1099 I think I can able do that. Since I am going to   client place to work not at my own office, I am not sure whether I   should able to do that or not. If you have LLC, unless you elected to tax it as a corporation, you need neither 1099 nor W2. For tax purposes the LLC is disregarded. So it is, from tax perspective, a sole proprietorship (or partnership, if multiple members). Being a W2 employee of your own LLC is a bad idea. For all these above expenses, which can I use company's debit/credit   card or I need to use only my personal debit/credit card? It would be better to always use a business account for business purposes. Doesn't matter much for tax per se, but will make your life easier in case of an audit or a legal dispute (limited liability protection may depend on it). If I work on 1099, I guess I need to file some reasonable taxes on   quarterly basis instead of filing at year end. If so, how do I pay my   tax on quarterly basis to IRS? I mean which forms should I file and   how to pay tax? Unless you're a W2 employee, you need to do quarterly estimate payments using form 1040-ES. If you are a W2 employee (even for a different job, and even if it is not you, but your spouse with whom you're filing jointly) - you can adjust your/spouse's withholding using form W4 to cover the additional tax liability. This is, IMHO, a better way than paying estimates. There are numerous questions on this, search the site or ask another one for details. "Your question does not say this explicitly, but I assume that you were once a W-2 employee.  Each paycheck a certain amount was withheld from your check to pay income, social security, and medicare taxes.  Just because you did not receive that amount of money earned does not mean it was immediately sent to the IRS.  While I am not all that savvy on payroll procedures, I recall an article that indicated some companies only send in withheld taxes every quarter, much like you are doing now.  They get a short term interest free loan.  For example taxes withheld by a w-2 employee in the later months of the year may not be provided to the IRS until 15 January of the next year.   You are correct in assuming that if you make 100K as a W-2 you will probably pay less in taxes than someone who is 100K self employed with 5K in expenses.  However there are many factors.  Provided you properly fill out a 1040ES, and pay the correct amount of quarterly payments, you will almost never owe taxes.  In fact my experience has been the forms will probably allow you to receive a refund.  Tax laws can change and one thing the form did not include last year was the .9% Medicare surcharge for high income earners catching some by surprise.    As far as what you pay into is indicative of the games the politicians play.  It all just goes into a big old bucket of money, and more is spent by congress than what is in the bucket.  The notion of a ""social security lockbox"" is pure politics/fantasy as well as the notion of medicare and social security taxes.  The latter were created to make the actual income tax rate more palatable.     I'd recommend getting your taxes done as early as possible come 1 January 2017.  While you may not have all the needed info, you could firm up an estimate by 15 Jan and modify the amount for your last estimated payment.  Complete the taxes when all stuff comes in and even if you owe an amount you have time to save for anything additional.  Keep in mind, between 1 Jan 17 and 15 Apr 17 you will earn and presumably save money to use towards taxes.  You can always ""rob"" from that money to pay any owed tax for 2016 and make it up later. All that is to say you will be golden because you are showing concern and planning.  When you hear horror stories of IRS dealings it is most often that people spent the money that should have been sent to the IRS." No there is no way to have untaxed earnings.  Single Member LLC are taxed on your personal taxes.  Partnership LLC is taxed on your and your partners personal taxes.  An C-Corp LLC has its own tax bracket.  An S-Corp is taxed on your personal taxes (but does not get taxed as self-employment taxes).   At $500,000, YOU SHOULD BE AN S-CORP or C-CORP to save on self-employment taxes. According to this section in Publication 15:  Collecting underwithheld taxes from employees.   If you withheld no   income, social security, or Medicare taxes or less than the correct   amount from an employee's wages, you can make it up from later pay to   that employee. But you’re the one who owes the underpayment.   Reimbursement is a matter for settlement between you and the employee.   [...] it seems that if the employer withheld less than the correct amount of FICA taxes from you, it is still the employer who owes your FICA taxes to the government, not you. I do not believe there is a way for you, an employee (not self-employed), to directly pay FICA taxes to the government without going through the employer. The employer can deduct the underwithheld amount from you future paychecks (assuming you still work for them), or settle it with you in some other way. In other words, you owe the employer, and the employer owes the government, but you do not directly owe the government. If they do deduct it from your future pay, then they can issue a corrected W-2, to reflect the amount deducted from you. But they cannot issue a corrected W-2 that says FICA were deducted from you if it wasn't.