Tax whilst starting a business in full time employment
With a limited company, you'll have to pay yourself a salary through PAYE. With income from your other job taking you over the higher-rate threshold, you should inform HMRC of this and get a tax code of DO for the second job, meaning 40% tax (and also both employer's and employee's National Insurance) will be deducted from the whole amount of the salary. See here.  Dividends should be like any other dividend -- you won't pay extra tax when you receive them, but will have to declare them on your tax return and pay the tax later. See the official information here. You'll get a £5,000 tax allowance for dividends, but they'll still count as income for purposes of hitting the higher-rate threshold. I think in practice this means the first £5,000 will be tax-free, and the rest will be taxed at 32.5%. But note that you have to pay yourself at least the minimum wage as salary, not as dividend.  I can't see IR35 being an issue.  However, I'm not a professional, and this situation is complicated enough to need professional advice. Talk to an accountant or a tax advisor.
"I don't see why you would need an ""international tax specialist"". You need a tax specialist to give you a consultation and training on your situation, but it doesn't seem too complicated to me. You invoice your client and get paid - you're a 1099 contractor. They should issue you a 1099 at the end of the year on everything they paid you. Once you become full-time employee - you become a W2 employee and will get a W2 at the end of the year on the amounts paid as such. From your perspective there's nothing international here, regular business. You have to pay your own taxes on the 1099 income (including SE taxes), they have to withhold taxes from your W2 income (including FICA). Since they're foreign employers, they might not do that latter part, and you'll have to deal with that on your tax return, any decent EA/CPA will be able to accommodate you with that. For the employer there's an issue of international taxation. They might have to register as a foreign business in your state, they might be liable for some payroll taxes and State taxes, etc etc. They might not be aware of all that. They might also be liable (or exempt) for Federal taxes, depending on the treaty provisions. But that's their problem. Your only concern is whether they're going to issue you a proper W2 and do all the withholdings or not when the time comes." "One way to do these sorts of calculations is to use the spreadsheet version of IRS form 1040 available here.  This is provided by a private individual and is not an official IRS tool, but in practice it is usually accurate enough for these purposes.  You may have to spend some time figuring out where to enter the info.  However, if you enter your self-employment income on Schedule C, this spreadsheet will calculate the self-employment tax as well as the income tax.  An advantage is that it is the full 1040, so you can also select the standard deduction and the number of exemptions you are entitled to, enter ordinary W-2 income, even capital gains, etc. Of course you can also make use of other tax software to do this, but in my experience the ""Excel 1040"" is more convenient, as most websites and tax-prep software tend to be structured in a linear fashion and are more cumbersome to update in an ad-hoc way for purposes like tax estimation.  You can do whatever works for you, but I would recommend taking a look at the Excel 1040.  It is a surprisingly useful tool." "If this is truly hobby income (you do not intend to operate as a business and don't have a profit motive) then report the income on Line 21 (""other income"") of form 1040.  If this is a business, then the income and expenses belong on a Schedule C to form 1040. The distinction is in the treatment of profits and losses - your net profits on a business are subject to self-employment tax, while hobby income is not. Net losses on a business are deductible against other income; net losses on a hobby are miscellaneous itemized deductions in the ""2%"" box on Schedule A.  From a tax point of view, selling apps and accepting donations are different. Arguably, donations are gifts; gifts are not taxable income.  The hobby/business and income/gift distinctions are tricky. If the dollar amounts are small, nobody (including the IRS) really cares. If you start making or losing a lot of money, you'll want to get a good tax person lined up who can help you decide how to characterize these items of income and expens, how to put them on your return, and how to defend the return on audit if necessary." "This is not an end-all answer but it'll get you started I have been through accounting courses in college as well as worked as a contractor (files as sole proprietor) for a few years but IANAA (I am not an accountant). Following @MasonWheeler's answer, if you're making that much money you should hire a bean counter to at least overlook your bookkeeping. What type of business? First, if you're the sole owner of the business you will most likely file as a sole proprietorship. If you don't have an official business entity, you should get it registered officially asap, and file under that name. The problem with sole proprietorships is liability. If you get sued, not only are your business' assets vulnerable but they can go after your personal assets too (including house/cars/etc). Legally, you and your business are considered one and the same. To avoid liability issues, you could setup a S corporation. Basically, the business is considered it's own entity and legal matters can only take as much as the business owns. You gain more protection but if you don't explicitly keep your business finances separate from your personal finances, you can get into a lot of trouble. Also, corporations generally pay out more in taxes. Technically, since the business is it's own entity you'll need to pay yourself a 'reasonable salary'. If you skip the salary and pay yourself the profits directly (ie evade being taxed on income/salary) the IRS will shut you down (that's one of the leading causes of corporations being shut down). You can also pay distribute bonuses on top of that but it would be wise to burn the words 'within reason' into your memory first. The tax man gets mad if you short him on payroll taxes.  S corporations are complicated, if you go that route definitely seek help from an accountant. Bookkeeping If you're not willing to pay a full time accountant you'll need to do a lot of studying about how this works. Generally, even if you have a sole proprietorship it's best to have a separate bank account for all of your business transactions. Every source/drain of money will fall into one of 3 categories... Assets - What your business owns: Assets can be categorized by liquidity. Meaning how fast you can transform them directly into cash. Just because a company is worth a lot doesn't necessarily mean it has a lot of cash. Some assets depreciate (lose value over time) whereas some are very hard to transform back into cash based on the value and/or market fluctuations (like property). Liabilities - What you owe others and what others owe you: Everything you owe and everything that is owed to you gets tracked. Just like credit cards, it's completely possible to owe more than you own as long as you can pay the interest to maintain the loans. Equity - the net worth of the company: The approach they commonly teach in schools is called double-entry bookkeeping where they use the equation: In practice I prefer the following because it makes more sense: Basically, if you account for everything correctly both sides of the equation should match up. If you choose to go the sole proprietorship route, it's smart to track everything I've mentioned above but you can choose to keep things simple by just looking at your Equity. Equity, the heart of your business... Basically, every transaction you make having to do with your business can be simplified down to debits (money/value) increasing and credits (money/value) decreasing. For a very simple company you can assess this by looking at net profits. Which can be calculated with: Revenues, are made up of money earned by services performed and goods sold. Expenses are made up of operating costs, materials, payroll, consumables, interest on liabilities, etc. Basically, if you brought in 250K but it cost you 100K to make that happen, you've made 150K for the year in profit. So, for your taxes you can count up all the money you've made (Revenues), subtract all of the money you've paid out (Expenses) and you'll know how much profit you've made. The profit is what you pay taxes on. The kicker is, there are gray areas when it comes to deducting expenses. For instance, you can deduct the expense of using your car for business but you need to keep a log and can only expense the miles you traveled explicitly for business. Same goes for deducting dedicated workspaces in your house. Basically, do the research if you're not 100% sure about a deduction. If you don't keep detailed books and try to expense stuff without proof, you can get in trouble if the IRS comes knocking. There are always mythical stories about 'that one guy' who wrote off his boat on his taxes but in reality, you can go to jail for tax fraud if you do that. It comes down to this. At the end of the year, if your business took in a ton of money you'll owe a lot in taxes. The better you can justify your expenses, the more you can reduce that debt. One last thing. You'll also have to pay your personal federal/state taxes (including self-employment tax). That means medicare/social security, etc. If this is your first foray into self-employment you're probably not familiar with the fact that 1099 employers pick up 1/2 of the 15% medicare/social security bill. Typically, if you have an idea of what you make annually, you should be paying this out throughout the year. My pay as a contractor was always erratic so I usually paid it out once/twice a year. It's better to pay too much than too little because the gov't will give you back the money you overpaid. At the end of the day, paying taxed sucks more if you're self-employed but it balances out because you can make a lot more money. If as you said, you've broken six figures, hire a damn accountant/adviser to help you out and start reading. When people say, ""a business degree will help you advance in any field,"" it's subjects like accounting are core requirements to become a business undergrad. If you don't have time for more school and don't want to pay somebody else to take care of it, there's plenty of written material to learn it on your own. It's not rocket surgery, just basic arithmetic and a lot of business jargon (ie almost as much as technology)." Assuming this to be in the UK, and I suspect  the rules are similar elsewhere, this indeed may be true. There is a threshold beneath which a business does not have to register for VAT - currently a turnover of £81,000. A non VAT registered business does not charge VAT but also cannot reclaim the VAT on their business expenses. For some businesses below the threshold it is worthwhile registering because the amount they can reclaim is significant. However, there are also many small businesses that do a lot of cash only jobs so as to not put the money through the books and therefore avoid any tax liability. There are also many who will get the the customer to buy materials direct to avoid including these in their turnover.  Like every type of tax rule there is a grey area between people trying to avoid paying more tax than is needed and dodgy deals to avoid paying their fair share of tax. The short Answer is NO, HMRC do not like disguised employment which is what this is as you fall under IR35 you can bill them via an umbrella company and you should be charging the contractor rate not a permie rate.  http://www.contractoruk.com/ "If a country had a genuine completely flat income tax system, then it wouldn't matter who paid the tax since it doesn't depend on the employee's other income. Since not many countries run this, it doesn't really make sense for the employee to ""take the burden"" of the tax, as opposed to merely doing the administration and paying the (probable) amount of tax at payroll, leaving the employee to use their personal tax calculation to correct the payment if necessary. Your prospective employer is probably saying that your tax calculation in Singapore is so simple they can do it for you. They may or may not need to know a lot of information about you in order to do this calculation, depending what the Singapore tax authorities say. If you're not a Singapore national, they may or may not be relying on bilateral tax agreements with your country to assert that you won't have to pay any further tax on the income in your own country. It's possible they're merely asserting that you won't owe anything else in Singapore, and in fact you will have taxes to report (even if it's just reporting to your home tax authority that you've already paid the tax). Still, for a foreign worker a guarantee you won't have to deal with the local tax authority is a good thing to have even if that's all it is. Since there doesn't appear to be any specific allowance for ""tax free money"" in the Singapore tax system, it looks like what you have here is ""just"" the employer agreeing to do something that will normally result in the correct tax being paid in your behalf. This isn't uncommon, but it's also not exactly what you asked for. And in particular if you have two jobs in Singapore then they can't both be doing this, since tax is not flat. The example calculation includes varying tax rates for the first X amount of income that (I assume without checking) are per person, not per employment. Joe's answer has the link. In practice in the UK (for example), there are plenty of UK nationals working in the UK who don't need to do a full tax return and whose tax is collected entirely at source (between PAYE and deductions on bank interest and suchlike). In this sense the employer is required by law to take the responsibility for doing the admin and making the tax payments to HMRC. Note that a UK employer doesn't need to know your circumstances in detail to make the correct payroll deductions: all they need is a so-called ""tax code"", which is calculated by HMRC and communicated to the employer, and which basically encodes how much they can pay you at zero rate before the various tax rate tiers kick in. That's all the employer needs to know here for the typical employee: they don't need to know precisely what credits and liabilities resulted in the figure. However, these employers still don't offer empoyees a net salary (that is, they don't take on the tax burden), because different employees will have different tax codes, which the employer would in effect be cancelling out by offering to pay two people the same net salary regardless of their individual circumstances. The indications seem to be that the same applies in Singapore: this offer is really a net salary subject to certain assumptions (the main one being that you have no other tax liabilities in Singapore). If you're a Singapore millionaire taking that job for fun, you might find that the employer doesn't/can't take on your non-standard tax liability on this marginal income." Normally, incorporation is for liability reasons.  Just file your taxes as a business.  This just means adding a T2125 to your personal return.  There's no registering, that's for GST if over a certain threshold. There's even a section in the instructions for internet businesses. http://www.cra-arc.gc.ca/E/pub/tg/t4002/t4002-e.html#internet_business_activities This is the form you have to fill out.  Take note that there is a place to include costs from using your own home as well.  Those specific expenses can't be used to create or increase a loss from your business, but a regular business loss can be deducted from your employment income. http://www.cra-arc.gc.ca/E/pbg/tf/t2125/t2125-15e.pdf