The State Pre-Tax Deduction Override Table identifies deduction's pre-tax rules per State Code. For those deductions that require a state pre-tax deduction override, these can be defined on the State Pre-Tax Deduction Overrides Table.
Choose the "Deduction State PreTax" screen from Validation Table Maintenance. A "Pre-Tax State" button on the Deduction Codes Table provides a shortcut to the table and filters by the selected deduction.
The State Pretax Deduction Override is primarily used for the State of Pennsylvania. PA isn't state-tax exempt for 401k deferrals.