To calculate capital gains and losses you must know the cost basis of the stock.
When selling stock that was acquired at different times, the IRS allows the word "Various" to be entered in the field for Date Acquired.*
If some of the shares sold end up being short-term (owned one year or less) and some of them are long-term, then you would need to split this sale into two separate transactions in the program.
You will need to determine the cost of each share you sold. Normally, when you sell stock that was acquired at different times and you sell some but not all of the shares, the basis is the basis of the shares of stock you acquired first. The shares you first acquired would be considered sold first. You cannot use an average cost basis; this is only allowed when buying mutual funds.
Our software does not keep track of your stock basis (purchase price). This should be maintained in your records. The plan administrator at your place of employment or your brokerage company could provide you with the history of your account in order to determine the purchase prices.
We do not provide a portfolio tracking tool to keep track of all of your purchases. We only support the entry for transactions that were sold during the year, since that is what is reportable on your return. The entry for "purchase price or other basis" is to be the total cost to you. We do not ask for number of shares and share price, which is normally totaled for you on your confirmation receipt from the broker when you bought the stock.
For more information, see
IRS Publication 550 Investment Income and Expenses, Chapter 4
Basis of Investment Property, and
IRS Publication 551 Basis of Assets. This gives some guidance in computing basis in stocks and bonds.
*
TaxACT supports an entry of "Various" as the date acquired on Form 1099-B. You would enter the data on Form 1099-B in the Investment Income section of TaxACT. Enter "Various" for date acquired, then enter the cost basis, date sold, and sales proceeds. The holding period will be determined based upon the reporting category you select (A-C for short-term; D-F for long-term), if one has already been selected. However, if a reporting category has not already been selected, the program will default to reporting category A, indicating a short-term transaction.