Working out if I should be registered as self-employed in the UK
As 'anonymous' already mentioned, I think the correct answer is to go see an accountant. That said, if you are already have to fill in a tax return anyway (ie, you're already a high rate taxpayer) then I don't see why it should be an issue if you just told HMRC of your additional profit via your tax return. I never was in the situation of being employed with a side business in the UK, only either/or, but my understanding is that registering as self employed is probably more suitable for someone who doesn't PAYE already. I might be wrong on this as I haven't lived in the UK for a couple of years but an accountant would know the answer. Of course in either case, make sure that you keep each an every scrap of paper to do with your side business. "Being self employed just means you fill out some more forms in your annual self assessment for your ""profit"" from being self employed.  Profit = all the money you receive, minus any tax deductible cost that you spent for making that money (and all the cost must be documented, which means you have a folder with all the receipts and keep it safe). You pay normal income tax on all the profit, which means it is just added to your taxable income. What you do with the profit is up to you; you don't pay yourself a salary, just take the money (make sure you leave enough to pay your taxes)."
"There are a couple of things that are missing from your estimate. In addition to your standard deduction, you also have a personal exemption of $4050.  So ""D"" in your calculation should be $6300 + $4050 = $10,350. As a self-employed individual, you need to pay both the employee and employer side of the Social Security and Medicare taxes.  Instead of 6.2% + 1.45%, you need to pay (6.2% + 1.45%) * 2 = 15.3% self-employment tax. In addition, there are some problems with your calculation. Q1i (Quarter 1 estimated income) should be your adjusted annual income divided by 4, not 3 (A/4). Likewise, you should estimate your quarterly tax by estimating your income for the whole year, then dividing by 4.  So Aft (Annual estimated federal tax) should be: Quarterly estimated federal tax would be: Qft = Aft / 4 Annual estimated self-employment tax is: Ase = 15.3% * A with the quarterly self-employment tax being one-fourth of that: Qse = Ase / 4 Self employment tax gets added on to your federal income tax.  So when you send in your quarterly payment using Form 1040-ES, you should send in Qft + Qse. The Form 1040-ES instructions (PDF) comes with the ""2016 Estimated Tax Worksheet"" that walks you through these calculations." "Can she claim deductions for her driving to and from work? Considering most people use their cars mostly to commute to/from work, there must be limits to what you can consider ""claimable"" and what you can't, otherwise everyone would claim back 80% of their mileage. No, she can't. But if she's driving from one work site to another, that's deductible whether or not either of the work sites is her home office. Can she claim deductions for her home office? There's a specific set of IRS tests you have to meet. If she meets them, she can. If you're self-employed, reasonably need an office, and have a place in your house dedicated to that purpose, you will likely meet all the tests. Can I claim deductions for my home office, even though I have an official work place that is not in my home? It's very hard to do so. The use of your home office has to benefit your employer, not just you. Can we claim deductions for our home internet service? If the business or home office uses them, they should be a deductible home office expense in some percentage. Usually for generic utilities that benefit the whole house, you deduct at the same percentage as the home office is of the entire house. But you can use other fractions if more appropriate. For example, if you have lots of computers in the home office, you can deduct more of the electricity if you can justify the ratio you use. Run through the rules at the IRS web page." If I remember correctly, once you're about to exceed the threshold you really don't have a choice and have to register for VAT. As DumbCoder mentions, the quarterly VAT returns isn't that much of a hassle, plus if you fall under a certain threshold, you can sign up for the annual accounting scheme for VAT, which means you'll have to only put in a single return, but HMRC takes more payments out over the course of the year. This is what I did when I ran my own limited company in the UK. "Yea. Almost every form I fill out wants to know ""Employer Name"". They don't even bother checking ""Are you Self Employed"". Of course, I end up writing ""Self Employed"" in employer name field anyway.   In the United States, it is even harder because EVERY state has their own labor and employment laws. You are a freelancer but what if you need to travel to a client site in a different state. Bam, you gotta file taxes for that state as well even if you made like a few hundred bucks.   Too much red tape and it is really hard to change." Is this for the US? Or does it apply here in the UK in a general sense?  Obviously I think we are using different terms, but this is just a general run down of the different business types really right?  I'm wondering if the use of a name thing matters here in the UK or not. I'm happy to trade under my actual name, but would prefer a name for the business that is separate to my own name. (1) Should I register for VAT?  – If it is below the threshold amount it is purely voluntary. If you register for VAT, you would have to charge VAT and then do returns every quarter. If you can take up this bit of hassle, it doesn't make much of a difference. One thing you need to consider: you get 1% discount during your first year of registering for VAT. If you want to save this discount for when you really need to pay VAT, it could be helpful. (2) What benefits would registering for VAT include?  – Except for reclaiming VAT, where you pay VAT for business expenses, not much. (3) Would I not just hold onto the monies for HMRC ?  – You wouldn't hold any money for HMRC. They will send you notifications if you do not file your returns and pay your VAT quarterly. And get everything cleared from your accountant. If your accountant doesn't answer properly, make it clear you need proper answers. Else change your accountant. If you do something wrong and HMRC gets after you, you would be held liable – your accountant can take the slip if you signed on all business documents provided by your accountant. Assuming you buy the services and products beforehand and then provide them to your clients. Should the cost of these products and services be deducted from my declared income or do I include them and then claim them as allowable expenses? You arrive at your final income after accounting for your incomings and outgoings ?  regularly buys products and services on behalf of clients These are your expenses. invoice them for these costs after These are your earnings. These are not exactly allowable expenses, but more as the cost of doing your business, so it will be deducted from your earnings. There will be other business expenses which you need to deduct from your earnings and then you arrive at your income/profit. So before you arrive at your income all allowable expenses have been deducted. include on my invoices to clients  VAT if you charge VAT. Any charges you require them to pay i.e. credit card charges etc. You don't need to inform clients about any costs you incur for doing your business unless required by law. If you are unsure about something browse the gov.uk website or obtain the services of an accountant. Accounting issues might be costly on your pocket if mistakes are committed. "If you have income - it should appear on your tax return. If you are a non-resident, that would be 1040NR, with the eBay income appearing on line 21. Since this is unrelated to your studies, this income will not be covered by the tax treaties for most countries, and you'll pay full taxes on it. Keep in mind that the IRS may decide that you're actually having a business, in which case you'll be required to attach Schedule C to your tax return and maybe pay additional taxes (mainly self-employment). Also, the USCIS may decide that you're actually having a business, regardless of how the IRS sees it, in which case you may have issues with your green card. For low income from occasional sales, you shouldn't have any issues. But if it is something systematic that you spend significant time on and earn significant amounts of money - you may get into trouble. What's ""systematic"" and how much is ""significant"" is up to a lawyer to tell you."