Does FIFO cost basis applies across multiple accounts?
You decide on a cost bases attribution yourself, per transaction (except for averaging for mutual funds, which if I remember correctly applies to all the positions). It is not a decision your broker makes. Broker only needs to know what you've decided to report it to the IRS on 1099, but if the broker reported wrong basis (because you didn't update your account settings properly, or for whatever else reason) you can always correct it on form 8949 (columns f/g). To sum up: My question came from misunderstanding what cost basis applies to. Now I get it that it applies to stocks as physical entities. Consider a chain of buys of 40 stock A with prices $1-$4-$10-$15 (qty 10 each time) then IRS wants to know exactly which stock I am selling. And when I transfer stocks to different account, that cost basis transfers with them. Cost basis is included in transfers, so that removes ambiguity which stock is being sold on the original account. In the example above, cost basis of 20 stocks moved to a new account would probably be $1 x 10 and $4 x 10, i.e. FIFO also applies to transfers.
The question is valid, you just need to work backwards. After how much money-time will the lower expense offset the one time fee?  Lower expenses will win given the right sum of money and right duration for the investment. Not to my knowledge. Often the specific location is diversified out of the fund because each major building company or real estate company attempts to diversify  risk by spreading it over multiple geographical locations. Also, buyers of these smaller portfolios will again diversify by creating a larger fund to sell to the general public. That being said, you can sometimes drill down to the specific assets held by a real estate fund. That takes a lot of work: You can also look for the issuer of the bond that the construction or real estate company issued to find out if it is region specific. Hope that helps. No. If you didn't specify LIFO on account or sell by specifying the shares you wish sold, then the brokers method applies.  From Publication 551 Identifying stock or bonds sold.   If you can adequately identify the   shares of stock or the bonds you sold, their basis is the cost or   other basis of the particular shares of stock or bonds. If you buy and   sell securities at various times in varying quantities and you cannot   adequately identify the shares you sell, the basis of the securities   you sell is the basis of the securities you acquired first. For more   information about identifying securities you sell, see Stocks and   Bonds under Basis of Investment Property in chapter 4 of Pub. 550. The trick is to identify the stock lot prior to sale. The technical feature exists to (1)block all ACH activity, (2)block all ACH credits, or (3)block all ACH debits attempting to post to the deposit account.  The large financial institutions will not deviate from their company policies and won't offer something like this for a personal account.  The smaller institutions and credit unions are much more willing to discuss options.  Especially if you maintain a large deposit balance or have many products with the institution, you might convince them this feature is very important and insist they block all ACH activity on your account. This feature is used frequently on controlled asset accounts where the balance must be frozen for a variety of reasons. Generally speaking, granting rights to one bank account (e.g. making a joint account) does not extend rights to other accounts or otherwise let one joint owner create new obligations on the other owner (e.g. opening a line of credit that the other owner must pay for), except to the extent of the joint account.  I assume there are no UK rules that would change this feature. The other party can of course withdraw all the money without need for your approval.  This also means that the joint account could be exposed to all the creditors of either party.  If your account joint tenant has huge debts, the creditors could theoretically look to the joint account for satisfaction.  At least, that would be an issue under US law. Frankly, it may be simpler to get a separate account for the other person (if possible) and make transfers with online banking.  It could also make sense to get a rechargeable banking card, if those are in the UK, which works like a debit card and can be reloaded through various means (sometimes a call, sometimes online deposits, sometimes in physical stores).  There may be fees to getting such a card or a second account, of course.  The benefit is that the cardholder has no access to your account and you control recharging.  Such cards are widely available in the US to people who otherwise would not qualify for traditional bank accounts. Note also the FATCA complication with adding a US person to your account.  My understanding is that a number of non-US banks will simply close the accounts of Americans, rather than deal with FFI hassles under FATCA. The key point is from the penultimate sentence in your second paragraph: for which you have already paid taxes When you receive a dividend or realise a capital gain, you get taxed on that then, and you shouldn't have to pay taxes on it again in future. So the cost basis gets adjusted to reflect that. "Nobody knows for sure what ""substantially identical"" means because the IRS hasn't officially defined it. Until they do so, it would come down to the decision of an auditor or a tax court. The rule of thumb that I have always heard is if the funds track the same index, they are probably substantially identical. I think most people wouldn't consider any pair of AGG, CMF, and NYF to be substantially identical, so you should be safe with your tax-loss harvesting strategy." This is great! I'm not a CPA, but work in finance. As such, my course/professional work is focused more on the economic and profitability aspects of transfer pricing. As you might imagine, it tended to analyze corporate strategy decisions under various cost allocation models, which you thoroughly discuss.  I would agree with the statement that it is based on the matching principle but would like to add that transfer pricing is interesting as it falls under several fields: accounting, finance, and economics. Fundamentally it is based on the matching principal, but it's real world applications are based on all three (it's often used to determine divisional and even individual sales peoples profitability; as is the case with bank related funds transfer pricing on stuff like time deposits). In this case, the correct accounting principal allows you to, when done properly, better understand the economics, strategy, and operations of an organization.   In effect, when done correctly, it provides transparency for strategic decision making to executives. As I said, since my coursework tended to focus more on that aspect, I definitely have a natural tendency towards it.  This is an amazing explanation (esp. about interest on M&amp;A bridge loans, I get that) of the more detailed stuff! Truthfully, I'm not as familiar with it and was just trying to show more of the conceptual than nitty-gritty.   Thanks for the reply! Check out personal finance. But, my guess is no. Given you are married and you were prepared to contribute $x out of the entire family pot, why don't they just contribute $x from their portion of the entire family pot? Net effect should be similar or identical. (I'm not an accountant nor married, so enjoy the grain of salt). In the US you specify explicitly what stocks you're selling. Brokers now are required to keep track of cost basis and report it to the IRS on the 1099-B, so you have to tell the broker which position it is that you're closing. Usually, the default is FIFO (i.e.: when you sell, you're assumed to be closing the oldest position), but you can change it if you want. In the US you cannot average costs basis of stocks (you can for mutual funds), so you either do FIFO, LIFO (last position closed first), or specify the specific positions when you submit the sale order. If you go through the web pages of some online brokers, you will find out that some of them allow you to manage friends/relatives accounts from your account as a trusteer. That should really solve your underlying problem, you will need only one login, etc. (Example: https://www.interactivebrokers.com/ff/en/main.php) If I understand it right it will even allow you to make one trade splitting the cost and returns among the other accounts, but you would have to verify that. Anyways, that will save you a lot of trouble and your broker can probably help you with the legal necessities. Each goes to a different agency. Yes, it is normal that the lender queries more than one agency. "JoeTaxpayer's answer mentions using a third ""house"" account. In my comment on his answer, I mentioned that you could simply use a bookkeeping account to track this instead of the overhead of an extra real bank account. Here's the detail of what I think will work for you. If you use a tool like gnucash (probably also possible in quicken, or if you use paper tracking, etc), create an account called ""Shared Expenses"". Create two sub accounts under that called ""his"" and ""hers"". (I'm assuming you'll have your other accounts tracked in the software as well.) I haven't fully tested this approach, so you may have to tweak it a little bit to get exactly what you want. When she pays the rent, record two transactions: When you pay the electric bill, record two transactions: Then you can see at a glance whether the balances on ""his"" and ""hers"" match." The $47.67 per share figure is the trading price, or fair market value, of the OLD Johnson Controls, and should not be used to figure your gain nor to figure your basis in the new Johnson Controls International. Your new basis is the total of the gross proceeds received; that is, the cash  plus the fair market value of the new shares, which was $45.69 per share. (I am not referring to cash-in-lieu for fractional shares, but the $5.7293 per share received upon the merger.) A person holding 100 shares of the old Johnson Controls would have received $572.93, plus 83.57 shares of the new company.  Ignoring the fractional share, for simplicity's sake, gross proceeds would equal 83 x $45.69 = $3792.72  in fair market value of shares, plus the cash of $572.93, for a total of $4365.20. This is your basis in the 83 new shares. Regarding the fractional share, since new basis is at fair market value, there should be no gain or loss recognized upon its sale. "I don't know if this is ""valid"" from a bookkeeping/accounting standpoint, but I'm just trying to keep records for myself so this works for me unless someone has another suggestion. I created two Expense accounts for the HSA (Roth, etc would work the same way): (""CY"" meaning current year.) When I make a $50 contribution, I enter the following splits: When you look at this in the Accounts tab, it shows the parent account with a zero balance (because the subaccount balance is positive and the parent account is negative). The subaccount has the balance accumulated so far; this lets me see the YTD contributions to my HSAs. At the end of the year I will make a closing transaction in the opposite direction (for whatever the total balance of the CY account is): This will zero-balance these two accounts. The only complication I see remaining is the issue of making contributions for the prior year during the January-April time frame. I don't generally make current-year contributions followed by prior-year contributions, so I can just wait to enter the closing transaction until I know I'm done with prior-year contributions."