This from Scottrade:
How will Scottrade calculate my gains and losses?
There are seven different tax strategies by which Scottrade can calculate your gains and losses on equities, and you may select which one we use on a trade-by-trade basis or choose a single method to be applied to all transactions. The available tax strategies for equities are FIFO (first in, first out), LIFO (last in, first out), HIFO (highest in, first out), Minimum Tax, Maximum Gain and Versus Purchase. For mutual funds, Average Cost is an additional method that can be selected. Each one has advantages and disadvantages depending on your personal tax strategy, and you can learn more about them in the Tax Strategies section of the Knowledge Center. Unless you instruct otherwise, Scottrade will use FIFO to calculate your gains and losses.
What do I need to do to choose a tax strategy?
To specify your tax strategy, also known as your 'tax lot relief' method, on a particular transaction, you will need to go into the Gain/Loss and Tax Center under the My Account tab in your account to make your selection. You will be able to make any changes you'd like from the day following execution up to and including the trade settlement date. For equities, the settlement date is three market days following the date the order executes.
After the settlement date of your trade, you will not be able to make any further adjustments to your tax strategy (covered positions only). That's why it is in your best interests to understand the tax implications of your decision at the time of a transaction.
What if I don't do anything?
Many investors will do nothing at all. If you do not make any changes to your tax strategy, Scottrade will use FIFO (first in, first out).
