This calculator works out the profits and tax basis periods for unincorporated businesses in various situations.
The Basis Period Tool works out the profits and tax basis periods for unincorporated businesses where special rules apply; the first and second tax years in which a business trades, when there is a change of accounting date and when a business ceases to trade.
Enter the required data in the blue cells. You can read further information about the data you need to enter by clicking the “Information” button.