etrade sp help, page-2

From the portfolio screen

To update your cost basis of a stock in your portfolio, select 'Detailed View' in the "View Type" drop-down menu above. Click the 'TOOLS +' button next to the stock you wish to edit, and then select 'Edit'. Learn more »

You can change the “Cost Basis” at which you purchased shares in both your portfolio as well as your watchlist. This is particularly valuable in your portfolio where you transfer holdings across from another broker to us. When this is done, we will not be aware of the price you purchased your holdings or the date you acquired them – this is where you can update it.


To change your cost basis and date acquired in your portfolio:

On the "My Portfolio" tab, choose the relevant portfolio you would like to update in the "Portfolio/Watchlist" drop down box.
Choose "Detailed View" in the "View Type" drop down box and click "Go".
Once the portfolio loads, scroll over the “TOOLS +” icon beside the stock entry you wish to adjust and choose the "Edit" link.
On the next page you will be able to update the cost basis and the date acquired using the format "DD/MM/YYYY".
Once entered, click "Update".