What's the Difference Between Regular and Supplemental Runs

This table describes how regular and supplemental payroll runs calculate federal taxes, based on the default settings.

For this payment type	And this process and pay option	Taxes regular runs this way	Taxes supplemental runs this way
Standard	Process and pay with other earnings	Annualized	N/A
Standard	Process and pay with other earnings	Annualized, Aggregation	N/A
Standard	Process separately but pay with other earnings	Annualized (Standard Earnings) + Tiered Flat Rate (Supplemental Earnings)	N/A
Standard	Process separately and pay separately	Annualized (Standard Earnings) + Tiered Flat Rate (Supplemental Earnings) for two separate pays	N/A
Supplemental	Process and pay with other earnings	Annualized, Aggregation	Tiered Flat Rate
Supplemental	Process separately but pay with other earnings	Annualized (Standard Earnings) + Tiered Flat Rate (Supplemental Earnings)	Tiered Flat Rate
Supplemental	Process separately and pay separately	Tiered Flat Rate	Tiered Flat Rate
Supplemental	Process separately and pay separately	Annualized (Standard Earnings) + Tiered Flat Rate (Supplemental Earnings) for two separate pays	Tiered Flat Rate

For further info, see How Supplemental Earnings Are Calculated in a Regular Run in the US in the Help Center.