How is Massachusetts state tax on unrealized capital gains calculated?
"Massachusets does no such thing. The 5.25% tax is only on realized gains. ""Unearned"" means ""doesn't tie to your trade/business"", i.e.: is not gained through your personal performance."
Both states will want to tax you. Your tax home is where you maintain a domicile, are registered to vote, etc. and you will probably want to keep this as MA since you state that MA is your permanent residence and you are staying in a rented place in PA. But be careful about voter registration; that is one of the items that can be used to determine your state of residence.  OK, so if you and your spouse are MA residents,  you should file jointly as residents in MA and as nonresidents in PA. Do the calculations on the nonresident return first, and then the calculations on the resident  return. Typically, on a nonresident tax return, the calculations are effectively the following: Report all your income (usually AGI from the Federal return).  Call this $X. Compute the PA state tax due on $X.  Note that you follow the rules for nonresidents in doing this, not the calculations used by PA residents. Call the amount of tax you computed as $Y. What part of the total income $X is attributable to PA sources? If this amount is $Z, then you owe PA $Y times (Z/X). On the resident return in MA, you will likely get some credit for the taxes paid to PA, and this will reduce your MA tax burden. Usually the maximum credit is limited to the lesser of actual tax paid to PA and what you would have had to pay MA for the same income. As far as withholding is concerned, your employer in PA will withhold PA taxes as if you are a PA resident, but you can adjust the amount via the PA equivalent of IRS Form W4 so as to account for any additional  tax that might be due because you will be filing as a nonresident.  Else you can pay estimated taxes via the PA equivalent of IRS Form 1040ES. Similarly, your wife can adjust her withholding to account for the MA taxes that you will owe on the joint income, or you can pay estimated taxes to MA too. Note that it is unlikely that your employer in Pennsylvania will withhold  Massachusetts taxes (and send them to Massachusetts) for you, e.g. if it is a ma-and-pa store, but there may be special deals available if  your employer does business in both states, i.e. is a MA-and-PA store. When you invest (say $1000) in (say 100 shares) of a mutual fund at $10 per share, and the price of the shares changes,  you do not have a capital gain or loss, and you do not have to declare anything to the IRS or make any entry on any line on Form 1040 or tell anyone else about it either. You can brag about it at parties if the share price has gone up, or weep bitter tears into your cocktail if the price has gone down, but the IRS not only does not care, but it will not let you deduct the paper loss or pay taxes on the paper gain.  What you put down on Form 1040 Schedules B   and D is precisely what the mutual fund will tell you on   Form 1099-DIV (and Form 1099-B), no more, no less. If you did not report any of these amounts on your previous   tax returns, you need to file amended tax returns, both   Federal as well as State, A stock mutual fund invests in stocks and the fund manager may buy and sell some stocks during the course of the year. If he makes a profit, that money will be distributed to the share holders of the mutual fund. That money can be re-invested in more shares of the same mutual fund or taken as cash  (and possibly invested in some other fund). This  capital gain distribution is reported to you on Form 1099-DIV and you have to report sit on your tax return even if you re-invested in more share of the same mutual fund, and the amount of the distribution is taxable income to you. Similarly, if the stocks owned by the mutual fund pay dividends, those will be passed on to you as a dividend distribution and all the above still applies. You can choose to reinvest, etc, the amount will be reported to you on Form 1099-DIV, and you need to report it to the IRS and include it in your taxable income. If the mutual fund manager loses money in the buying and selling he will not tell you that he lost money but it will be visible as a reduction in the price of the shares. The loss will not be reported to you on Form 1099-DIV and you cannot do anything about it.  Especially important, you cannot declare to the IRS that you have a loss and you cannot deduct the loss on your income tax returns that year. When you finally sell your shares in the mutual fund, you will have a gain or loss that you can pay taxes on or deduct. Say the mutual fund paid a dividend of $33 one year and you re-invested the money into the mutual fund, buying 3 shares at the then cost of $11 per share. You declare the $33 on your tax return that year and pay taxes on it. Two years later, you sell all 103 shares that you own for $10.50 per share.  Your total investment was $1000 + $33 = $1033. You get $1081.50 from the fund, and you will owe taxes on $1081.50 - $1033 = $48.50. You have a profit of $50 on the 100 shares originally bought and a loss of $1.50 on the 3 shares bought for $11: the net result is a gain of $48.50. You do not pay taxes on $81.50 as the profit from your original $1000 investment; you pay taxes only on $48.50 (remember that you already paid taxes on the $33). The mutual fund will report on Form 1099-B that you sold 103 shares for $1081.50 and that you bought the 103 shares for  an average price of $1033/103 = $10.029 per share. The difference is taxable income to you. If you sell the 103 shares for $9 per share (say),   then you get $927 out of an investment of $1033 for   a capital loss of $106. This will be reported to you   on Form 1099-B and you will enter the amounts on   Schedule D of Form 1040 as a capital loss. What you actually pay taxes on is the net capital gain, if any, after combining all your capital gains and losses for the year. If the net is a loss, you can deduct up to $3000 in a year, and carry the rest  forward to later years to offset capital gains in later years. But, your unrealized capital gains or losses (those that occur because the mutual fund share price goes up and down like a yoyo while you grin or grit your teeth and hang on to your shares) are not reported or deducted or taxed anywhere. It is more complicated when you don't sell all the shares you own in the mutual fund or if you sell shares within one year of buying them, but let's stick to simple cases. Stock awards by employers are treated and taxed as salary. I.e.: you pay ordinary rate income tax, FICA taxes, State taxes etc. The fact that you got your salary in shares and not cash is irrelevant for tax purposes. Once you got the shares and paid your taxes on them, the treatment is the same as if you got the salary and immediately bought the shares. Holding period for capital gains tax purposes starts at the time you paid your taxes on the award, which is the time at which you get full ownership (i.e.: vesting time, for the restricted stocks). When you sell these stocks - you treat the sale as any other stock sale: you check the holding period for capital gains tax rates, and you do not pay (or get refund) any FICA taxes on the sales transaction. So bottom line: You got $10K salary and you bought $10K worth of company stock, and you sold it at $8K half a year later. You have $10K wages income and $2K short term capital loss. Milliondollarjourney.com has a couple of articles on this topic. How Investing Taxes Work part 1 and part 2. The following is a summary of that article. Capital gains and dividends are taxed at a preferred rate, while interest tax is taxed at your regular rate. Interest is taxed at your marginal rate, but capital gains are taxed at only 50% of your marginal rate. That means that it makes sense to place the interest bearing account inside the RRSP but keep stocks outside. Additionally, you can claim your losses on your capital appreciating stocks against your gains if they are outside of your RRSP. Hopefully, your stocks will never go down but that's not very realistic. Dividends from Canadian companies are eligible for a dividend tax credit, but not dividends from foreign companies. [I actually understood that dividends from U.S. companies are treated as a special case] It's not clear to me from reading the article how much of this applies to mutual funds. The summary is as follows: If you have two other assets whose payoffs tomorrow are known and whose prices today are known, you can value it.  Let's say you can observe a risk-free bond and a stock. Using those, you can calculate the state prices/risk-neutral probabilities. NOTE: You do not need to know the true probabilities.   The value of your asset is then the state-price weighted sum of future payoffs. I use a spreadsheet for that.   I provide house value, land value, closing/fix-up costs, mortgage rate and years, tax bracket, city tax rate, insurance cost, and rental income.  Sections of the spreadsheet compute (in obvious ways) the values used for the following tables:  First I look at monthly cash flow (earnings/costs) and here are the columns:   Next section looks at changes in taxable reported income caused by the house,  And this too is monthly, even though it'll be x12 when you write your 1040.   The third table is shows the monthly cash flow, forgetting about maintenance and assuming you adjust your quarterlies or paycheck exemptions to come out even: Maintenance is so much of a wildcard that I don't attempt to include it.  My last table looks at paper (non-cash) equity gains:  I was asked how I compute some of those intermediate values.  My user inputs (adjusted for each property) are:  My intermediate values are: You should total the items first, to get $3.00, then add the tax, then round up/down accordingly.  Your two examples above don't offer this option, even though your second example arrives at the same result.  In your first example, a number of items taxed one at a time might result in many .006 results which would round to .01. A long enough list of items would result in an error of many cents depending how many items there are. Totaling first then applying tax results in your saving .004 or losing .005 cents maximum due to rounding.  See A Guide to Sales and Use Tax which is a document put out by the Massachusetts Dept of Revenue. In the chart for tax, it shows that $1.09 is taxed at five cents, but at 5%, it would be 5.45. So, at least for this state, I believe I correctly stated the rounding process. If you just want to know total return, either as dollars or a percentage, just add up the total amount spent on buys and compare this to current value plus money received on sales. In this case, you spent (310 x $3.15 + $19.95) + (277 x $3.54 + $19.95). So your total investment is ... calculator please ... $1996.98. You received 200 x $4.75 on the sale minus the $19.95 = $930.05. The present value of your remaining shares is 387 x $6.06 = $2345.22. So you have realized plus unrealized value of $2345.22 + $930.05 = $3275.27. Assuming I didn't mix up numbers or make an arithmetic mistake, your dollar gain is $3275.27 - $1996.98 = $1278.29, which comes to 1278.29 / 1996.98 = 64%. If you want to know percentage gain as an annual rate, we'd have to know buy and sell dates, and with multiple buys and sells the calculation gets messier.