Further Understanding of Wash Sale Rules
Disallowed losses due to the wash sale rule are added to the basis of the repurchased shares.  In your example, on day two you paid $0.70 per share. Then the disallowed $0.30 loss from the previous day gets added to the basis, making your total basis $1.00 per share. When you sell at the end of the day for $1.00 per share, your net gain/loss is zero. Furthermore, you can recapture disallowed losses by selling the last lot of ABC, completely divesting yourself of all holdings in ABC for at least 31 days. Even if that last lot was a loss, when taking into account the increased basis from previously disallowed wash sale losses, you can claim the loss fully on this last, non-wash sale. Once you own no shares for 31 days, it's game over. Even though the accounting has wash sales to consider, in the end, gains and losses all cancel to one net position of break even, gain or loss.  It's when there are shares remaining at the end of a period of time that the wash sale rules really impact the numbers.
Yes. On December 10, you have a wash sale. As long as you don't buy the stock back for 30 days after that, the wash is of no consequence. In other words, you don't have a wash issue if you don't own the stock for 30 days. "Yes- you do not realize gains or losses until you actually sell the stock.  After you sell the initial stocks/bonds you have realized the gain.  When you buy the new, different stocks you haven't realized anything until you then sell those. There is one exception to this, called the ""Wash-Sale Rule"".  From Investopedia.com: With the wash-sale rule, the IRS disallows a loss deduction from the   sale of a security if a ‘substantially identical security' was purchased within 30 days before or after the sale.  The   wash-sale period is actually 61 days, consisting of the 30 days before   and the 30 days after the date of the sale. For example, if you bought   100 shares of IBM on December 1 and then sold 100 shares of IBM on   December 15 at a loss, the loss deduction would not be allowed.   Similarly, selling IBM on December 15 and then buying it back on   January 10 of the following year does not permit a deduction. The   wash-sale rule is designed to prevent investors from making trades for   the sole purpose of avoiding taxes." Your question is missing too much to be answered directly. Instead - here are some points to consider. Short term gains taxed at your marginal rates, whereas long term gains have preferable capital gains rates (up to 20% tax rate, instead of your marginal rate). So if you're selling at gain, you might want to consider to sell FIFO and pay lower capital gains tax rate instead of the short term marginal rate. If you're selling at loss and have other short term gains, you would probably be better selling LIFO, so that the loss could offset other short term gains that you might have.  If you're selling at loss and don't have short term gains to offset, you can still offset your long term gains with short term losses, but the tax benefit will be lower. In this case - FIFO might be a better choice again. If you're selling at loss, beware of the wash sale rules, as you might not be able to deduct the loss if you buy/sell within too short a window. "There some specific circumstances when you would have a long-term gain. Option 1:  If you meet all of these conditions: Then you've got a long-term gain on the stock.  The premium on the option gets rolled into the capital gain on the stock and is not taxed separately.  From the IRS: If a call you write is exercised and you sell the underlying stock, increase your amount realized on the sale of the stock by the amount you received for the call when figuring your gain or loss. The gain or loss is long term or short term depending on your holding period of the stock. https://www.irs.gov/publications/p550/ch04.html#en_US_2015_publink100010630 Option 2: If you didn't hold the underlying and the exercise of the call that you wrote resulted in a short position, you might also be able to get to a long-term gain by buying the underlying while keeping your short position open and then ""crossing"" them to close both positions after one year. (In other words, don't ""buy to cover"" just ""buy"" so that your account shows both a long and a short position in the same security.  Your broker probably allows this, but if not you, could buy in a different account than the one with the short position.)  That would get you to this rule: As a general rule, you determine whether you have short-term or long-term capital gain or loss on a short sale by the amount of time you actually hold the property eventually delivered to the lender to close the short sale. https://www.irs.gov/publications/p550/ch04.html#en_US_2015_publink100010586 Option 1 is probably reasonably common.  Option 2, I would guess, is uncommon and likely not worthwhile. I do not think that the wash sale rules can help string along options from expiration to expiration though.  Option 1 has some elements of what you wrote in italics (I find that paragraph a bit confusing), but the wash sale does not help you out." I was not able to find any authority for the opinion you suggest. Wash sale rules should, IMHO, apply. According to the regulations, you attribute the newly purchased shares to the oldest sold shares for the purposes of the calculation of the disallowed loss and cost basis. (c) Where the amount of stock or securities acquired within the 61-day period is less than the amount of stock or securities sold or   otherwise disposed of, then the particular shares of stock or   securities the loss from the sale or other disposition of which is not   deductible shall be those with which the stock or securities acquired   are matched in accordance with the following rule: The stock or   securities acquired will be matched in accordance with the order of   their acquisition (beginning with the earliest acquisition) with an   equal number of the shares of stock or securities sold or otherwise   disposed of. You can resort to the claim that you have not, in fact, entered into the contract within 30 days, but when you gave the instructions to reinvest dividends. I don't know if such a claim will hold, but to me it sounds reasonable. This is similar to the rules re short sales (in (g) there). In this case, wash sale rules will not apply (unless you instructed to reinvest dividends within the 30 days prior to the sale). But I'd ask a tax professional if such a claim would hold, talk to a EA/CPA licensed in your state. "The IRS has been particularly vague about the ""substantially identical"" investment part of the wash rule.  Many brokers, Schwab for instance, say that only identical CUSIPs (exactly the same ETF) matter for the wash rule in their internal calculations, but warn that the IRS might consider two ETFs over the same index to be substantially identical.  In your case, the broker has chosen to call these a wash despite even having different underlying indices.  Talking to the broker is the first step as they will report it to the IRS.  Though technically you have the final say in your taxes about the cost basis,  discussing this with the IRS could be rather painful. First though it is probably worth checking with your broker about exactly what happened.  There are other wash sale triggers that frequently trip people up that may have been in play here." Reading IRS Regulations section 15a.453-1(c) more closely, I see that this was a contingent payment sale with a stated maximum selling price. Therefore, at the time of filing prior years, there was no way of knowing the final contingent payment would not be reached and thus the prior years were filed correctly and should not be amended. Those regulations go on to give an example of a sale with a stated maximum selling price where the maximum was not reached due to contingency and states that in such cases: When the maximum [payment] amount is subsequently reduced, the gross profit ratio will be recomputed with respect to payments received in or after the taxable year in which an event requiring reduction occurs. However, in this case, that would result in a negative gross profit ratio on line 19 of form 6252 which Turbo Tax reports should be a non-negative number.  Looking further in the regulations, I found an example which relates to bankruptcy and a resulting loss in a subsequent year: For 1992 A will report a loss of $5 million attributable to the sale, taken at the time determined to be appropriate under the rules generally applicable to worthless debts. Therefore, I used a gross profit ratio of zero on line 19 and entered a separate stock sale not reported on a 1099-B as a worthless stock on Form 8949 as a capital loss based upon the remaining basis in the stock sold in an installment sale.  I also included an explanatory statement with my return to the IRS stating: In 2008, I entered into an installment sale of stock. The sale was a contingent payment sale with a stated maximum selling price. The sales price did not reach the agreed upon maximum sales price due to some contingencies not being met. According to the IRS   Regulations section 15a.453-1(c) my basis in the stock remains at $500 in 2012 after the final payment. Rather than using a negative gross profit ratio on line 19 of form 6252, I'm using a zero ratio and treating the remaining basis as a schedule-D loss similar to worthless stock since the sale is now complete and my remaining basis is no longer recoverable. "Repurchase agreements are a way of financing a security position. You have a collateralized loan where you give your security in exchange for cash. Let's say you have a 10 year Treasury note paying 3.5% while the 1-week repurchase rate is 0.5%. You loan the security to someone with a promise to repurchase it from them some time in the future. You  collect the 3.5% coupon and you pay the 0.5% interest. Clearly it makes no sense for someone to collect interest on money and also collect coupon payments. And for the counter-party it makes no sense to be not getting coupon payments and also to be paying interest. This how one website explains the process: During the transaction, any coupon payments that come due belong to   the legal owner, the ""borrower."" However, when this happens, a cash   amount equal to the coupon is paid to the original owner, this is   called ""manufactured payment."" In order to avoid the tax payment on   the coupon, some institutions will repo the security to a tax exempt   entity and receive the manufactured payment and avoid the tax (""coupon   washing"") I find this unequivocal description to be the clearest During the life of the transaction the market risk and the credit risk   of the collateral remain with the seller. (Because he has agreed to   repurchase the asset for an agreed sum of money at maturity). Provided   the trade is correctly documented if the collateral has a coupon   payment during the life of the repo the buyer is obliged to pay this   to the seller."