Entering Your Estimated Tax Payments

Estimated tax payments are prepayments of income tax, usually quarterly, that you make to your federal, state or local taxing agency.

Enter all estimated tax payments, including state or local tax payments, on the federal side of the interview. TurboTax will then transfer the state/local tax payments you entered to your state return.

1. In TurboTax, click the Federal Taxes tab (Personal in the Home & Business version) and then click Deductions & Credits below it.
2. When you get to the How Do You Want To Go Through Deductions and Credits? screen, click the Explore on My Own link.
3. On the Your 2012 Deductions & Credits screen, scroll down to the Estimates and Other Taxes Paid section. 
4. Click Start or Update to the right of Estimates and follow the on-screen directions.

 The IRS provides Form 2210, which can be used to determine if you underpaid and, if you have, to resolve the issue.