Cost Basis - once you make your first sale, can you change it for subsequent sales, or are you locked into…
Well, the broker doesn't really care - - they're trying to help you to do your taxes because the IRS does care. So, there are irs rules on changing accounting methods but you need to stick with one method.
More on reddit.comExplaining average costing to Auditors!
I need to withdraw funds from Vanguard. They need to report the withdrawal on a cost basis on my 1099-B. They asked if I want to use average cost or a different method. How do I know which method is best for me?
Spec id can be better in a taxable account because you can choose to sell specific lots that may have a loss instead of a gain.
More on reddit.comMy understanding of cost basis methods
If you buy the asset at different times (eg: reinvested dividends) then your basis in each share is different.
Let's say I buy a $100 share of stock. Then a few months later, I buy another share for $120. A few months later I go to sell and the price is $140. I can sell the last share I bought and realize a $20 capital gain or the first share I bought an realize a $40 capital gain. If I had waited until 1 year since I bought the first share, selling the first share would be a long term capital gain while the 2nd share would be a short term capital gain.
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