The What If? Planner lets you forecast next year's tax bill. To access the planner, follow these steps:

1. Open your individual tax return (SA100).
2. Click on Check & Finish.
3. ​Click on What If (if available). 

If the What If option isn't available, check the following:

• Close and reopen TaxCalc to update your licence.
• Go to Help > Check for Updates.