https://proconnect.intuit.com/community/help-articles/help/how-to-enter-federal-and-state-interest-r... is for all products

For Lacerte:

To enter/edit the federal and state interest rates in the global options:

1. Click on Settings.
2. Click on Options.
3. Select the Interest Rates tab.
4. Click on the Get Interest Rates button to download the interest rates or manually enter the IRS interest rates for each period (format is X.XX).
5. Scroll down to the State Interest Rates section.
6. Enter the state rates manually for each period (format is X.XX).

1. Go to the Penalties & Interest screen:
   • Screen 8, Penalties & Interest (2210) (Individual)
   • Screen 11, Penalties & Interest (2220) (Corporate)
   • Screen 11, Penalties & Interest (2220) (S Corporate)
   • Screen 13, Penalties & Interest (2210) (Fiduciary)
   • Screen 14, Penalties & Interest (Exempt Organization)
2. Scroll down to the State Interest Rates section.
3. Enter the applicable interest rates under the Overrides Entries in Options (10 for 10%) subsection.
   For multi-state returns (except Exempt Organization):
   1. Hold down Ctrl+E for the applicable quarter.
   2. Enter the Amount.
   3. Select the applicable State from the drop down menu.
   4. Click OK once complete.
   5. Repeat steps i-iii for each applicable quarter and each state.
   6.