Turbotax does not track stock basis. an accounting program like Quicken, Quickbooks and others do.
pre 2008? in 2008 laws required brokers to track tax basis for securities acquired after 2007. Most if not all did this beforehand because they had to file tax reports with the IRS and taxpayers. It may be unanswerable if your brokerage changes hands or you change brokers. for example transferring stock A from Broker B to Broker R. if Broker R does not get the info from Broker b., then likely it will use market value on the date of transfer. However, it is you who is responsible for properly reporting when sold.
