SUTA effective dates determine when a new state unemployment tax rate should begin applying to payroll calculations. In Greenshades, payroll administrators can enter a new SUTA rate with a specific effective start date on the Unemployment Taxes page. The system stores historical rate records, automatically populates wage bases when available, and applies the correct unemployment tax rate based on the effective date. This helps payroll and compliance teams manage state unemployment tax updates accurately without relying on manual tracking or spreadsheets.