How does per-annum depreciation for taxes work after the first year of depreciation?
The first method is the correct one. You bought an asset worth of $1000 and you put it on your depreciation schedule. What it means is that you get to write off the $1000 over a certain period of time (and not at once, as you do with expenses). But the value you're writing off is the $1000 regardless of how much you've written off already. Assume you depreciate in straight line over 5 years (that's how you depreciate computers for Federal tax purposes, most states follow). For the simplicity of the calculation, assume you depreciate each year as a whole year (no mid-year/mid-quarter conventions). The calculation is like this: If you sell the computer - the proceeds above the adjusted basis amount are taxed as depreciation recapture up to the accumulated depreciation amount, and as capital gains above that. So in your case - book value is the adjusted basis at the end of the year (EOY), depreciation this year is the amount you depreciate in the year in question out of the total of the original cost, and the accumulated depreciation is the total depreciation including the current year. In Maryland they do not allow depreciating to $0, but rather down to 25% of the original cost, so if you bought a $1000 computer - you depreciate until your adjusted basis is $250. Depreciation rates are described here (page 5). For computers (except for large mainframes) you get 30% depreciation, with the last year probably a bit less due to the $250 adjusted basis limitation.
I would use neither method.  Taking a short example first, with just three compounding periods, with interest rate 10%.  The start value y0 is 1. So after three years the value is 1.331, the same as y0 (1 + 0.1)^3. Depreciating (like inflation) by 10% (to demonstrate) gets us back to y0 = 1 Appreciating and depreciating by 10% cancels out: Appreciating by 10% interest and depreciating by 3% inflation: This is the same as y0 (1 + 0.1)^3 (1 + 0.03)^-3 = 1.21805 So for 50 years the result is y0 (1 + 0.1)^50 (1 + 0.03)^-50 = 26.7777 Note You can of course use subtraction but the not using the inflation figure directly.  E.g. (edit: This appears to be the Fisher equation.) 2nd Note Further to comments, here is a chart to illustrate how much the relative performance improves when inflation is accounted for.  The first fund's return is 6% and the second fund's return varies from 3% to 6%.  Inflation is 3%. "That's a very clear explanation, thanks! So a few additional things if anyone will humor my curiosity...  1. By ""one-time"" tax, does that mean a company that has, say, $5B overseas could bring that back into the US and just be taxed $500M, then keep the remaining $4.5B?  2. Could a company choose a percentage of their overseas money to transfer into the US? Like, only bring in 8% of that $5B ($400M) and be taxed $40M, while keeping all the rest outside the US? Or would it be mandatory to bring it all over?  3. Would most companies just start that same practice of routing to tax havens again after this tax is implented?" Interesting.  How would they account for it? Monthly? And if so do they modify the cost basis for each lot for the month and then restate?   It's hard to imagine they do that.   I have a million questions regarding this topic do you know where in the regs it is covered? You pay taxes on capital gains when you realize your gains by selling the investment property.  Also, in the US, taxes on capital gains are computed at special rates depending on your current income level, and so when you realize your gains two years from now, you will pay taxes on the gains at the special rate then applicable to your income level for the year of sale. Remember also that the US Congress  can change the tax laws at any time between now and the time you sell your stocks, and so the rates you are looking at now may have changed too. Does this make sense? I'm concerned that by buying shares with post tax income, I'll have ended up being taxed twice or have increased my taxable income. ... The company will then re-reimburse me for the difference in stock price between the vesting and the purchase share price. Sure.  Assuming you received a 100-share RSU for shares worth $10, and your marginal tax rate is 30% (all made up numbers), either: or So you're in the same spot either way.  You paid $300 to get $1,000 worth of stock. Taxes are the same as well.  The full value of the RSU will count as income either way, and you'll either pay tax on the gains of the 100 shares in your RSU our you'll pay tax on gains on the 70 shares in your RSU and the 30 shares you bought.  Since they're reimbursing you for any difference the cost basis will be the same (although you might get taxed on the reimbursement, but that should be a relatively small amount). This first year I wanted to keep all of the shares, due to tax reasons and because believe the share price will go up. I don't see how this would make a difference from a tax standpoint. You're going to pay tax on the RSU either way - either in shares or in cash.  how does the value of the shares going up make a difference in tax? Additionally I'm concerned that by doing this I'm going to be hit by my bank for GBP->USD exchange fees, foreign money transfer charges, broker purchase fees etc.  That might be true - if that's the case then you need to decide whether to keep fighting or decide if it's worth the transaction costs. "Your corporation would file a corporate income tax return on an annual basis. One single month of no revenue doesn't mean much in that annual scheme of things. Total annual revenue and total annual expenses are what impact the results. In other words, yes, your corporation can book revenues in (say) 11 of 12 months of the year but still incur expenses in all months. Many seasonal businesses operate this way and it is perfectly normal. You could even just have, say, one super-awesome month and spend money the rest of the year. Heck, you could even have zero revenue but still incur expenses—startups often work like that at first. (You'd need investment funding, personal credit, a loan, or retained earnings from earlier profitable periods to do that, of course.) As long as your corporation has a reasonable expectation of a profit and the expenses your corporation incurs are valid business expenses, then yes, you ought to be able to deduct those expenses from your revenue when figuring taxes owed, regardless of whether the expenses were incurred at the same approximate time as revenue was booked—as long as the expense wasn't the acquisition of a depreciable asset. Some things your company would buy—such as the computer in your example—would not be fully deductible in the year the expense is incurred. Depreciable property expenses are deducted over time according to a schedule for the kind of property. The amount of depreciation expense you can claim for such property each year is known as Capital Cost Allowance. A qualified professional accountant can help you understand this. One last thing: You wrote ""write off"". That is not the same as ""deduct"". However, you are forgiven, because many people say ""write off"" when they actually mean ""deduct"" (for tax purposes). ""Write off"", rather, is a different accounting term, meaning where you mark down the value of an asset (e.g. a bad loan that will never be repaid) to zero; in effect, you are recognizing it is now a worthless asset. There can be a tax benefit to a write-off, but what you are asking about are clearly expense deductions and not write-offs. They are not the same thing, and the next time you hear somebody using ""write off"" when they mean ""deduction"", please correct them." "No, not really. This depends on the situation and the taxing jurisdiction. Different countries have different laws, and some countries have different laws for different situations. For example, in the US, some investments will be taxed as you described, others will be taxed as ""mark to market"", i.e.: based on the FMV difference between the end of the year and the beginning of the year, and without you actually making any transactions. Depends on the situation." Both US GAAP and IFRS are accrual basis frameworks. 99.9% of businesses report under those frameworks (or their local gaaps, but still accrual based). Usually it's public sector entities which are cash-basis in my experience.   Anyway, accrual basis has more to do with revenue recognition, not taxation, so that's not really relevant here. The value date of an invoice (ie in which moment it becomes taxable) depends on tax legislation (which sets the rules to determine the so called date of taxable event), not so much on accounting principles.   In many cases taxable rules are intertwined with cash collection/payment, however, to prevent creative accounting for tax evasion purposes. For example, provisions for various uncertain future events might be required by accounting rules, but the corresponding expenses are generally not deductible for tax purposes (so you won't be able to deduct them until the event actually occurs and you pay). Either way, (lease or buy), it's likely going to be an expense, not a depreciation. You would expense the entire lease amount - whatever that is in the year it was paid. A $2k-$3k computer probably isn't worth the trouble of recording it as a Fixed Asset and depreciating it yearly. I work for a company that buys thousands of PCs a year for its employees and we have a hard rule: If it's under $3k, it's an expense not an asset. If you were buying $20k-$50k servers, this would be a different conversation both because of the price and the life of the item. Because it's such a small amount (unless you really are buying $20k PCs), it doesn't really matter whether it's your biggest expense or not, it's likely just an expense. Though, no one is preventing you from depreciating it over 5 years if you wanted to. See: https://www.irs.gov/help-resources/tools-faqs/faqs-for-individuals/frequently-asked-tax-questions-answers/sale-or-trade-of-business-depreciation-rentals/depreciation-recapture/depreciation-recapture In summary: I would say your question is more of a business sense question than a tax question. Is it worth it to you to lease instead of buying because you are getting a new PC so often? Btw: every 2 years is not that often. It's average. Whatever your decision, I think the answer for taxes is the same: Expense it all in the year it was incurred unless you really want to spread it out and depreciate. I think this question is best answered by simply spending 40-60 minutes looking over the tax documents from last year and tracing thru the calculations.   As much as we might like to do so, we can't treat taxes like a black box. Tax law is much more complicated than it should be, but its much easier to understand taxes after you've filed them than before or during... at least you have solid numbers to look at. Your administrator will pull from last year's funds first, before automatically moving on to the new year.  The procedures are under guidelines from the IRS so it should be pretty standard. You likely only have to submit the claim once, but your administrator may have a special grace period form to fill out. The preparation for starting up of the company has lasted already more than 2 years. Let's say the company starts officially in January next year. So, in January 2014... 8 million USD is invested to purchase the equipments and the company will start selling their prdocuts right away. Imagine the company will be selling the same amount of products each year at the same price for 5 years. After 5 years it will sell the equipments for 6 million USD and cease to exist. The depreciation of  equipments is divided into those 5 years. So, each year the depreciation of equipments is 400.000 USD. In despite of this, the company will make 500.000 USD per year as a profit before tax.  So, the equipments are bought in Januardy 2014 (first month of the existence of the company) and sold in December 2018 (last month of the existence of the company). This is the NPV that I calculated. Is it correct? If you want to predict the, the easiest solution is to get hold of a copy of last year's tax forms and fill them in with estimated numbers.  Odds are that none of the more complicated deductions will apply to you this first time around, so I'd suggest just using the federal 1040EZ, and your state's equivalent, for this purpose. If it turns out that you can claim anything more than the standard deduction, that would reduce your taxes, so this is leaning toward the safe side. "Cars depreciate the most their first year after introduction. So you could buy a ""new"" car in year 2 for the optimal price, and at year 4 (when you finish paying yours off) you could buy the next car in year 2 (this is surprisingly similar to rolling options in a buy-write strategy, an arguably more constructive use of your money)" Profit = Sale price - Basis Basis = Purchase price - any depreciation taken, including expensing it.