This module focuses on building taxable income from pre-tax book income through common book-to-tax adjustments. You will work with M-1 style items such as federal income tax expense, travel and entertainment disallowance, depreciation differences, and other timing differences, while practicing the sign logic that determines whether each adjustment is added back or subtracted. You will also learn how to transfer a completed taxable income result into ONESOURCE and confirm field accuracy, sign consistency, and agreement to return output.

This module covers the basic federal corporate tax liability calculation and the estimated tax safe harbor framework used in routine compliance work. You will compute tax before credits using the 21% federal corporate rate, account for credits and estimated payments to determine balance due, and compare prior-year and current-year methods for quarterly estimated tax planning. The emphasis is on showing the sequence clearly so each result is traceable and easy to explain.

This module introduces the core logic of state apportionment for multistate businesses and highlights common calculation risks. You will calculate sales, payroll, and property factors, compare the traditional equally weighted three-factor formula with a single-sales-factor approach, and apply the correct apportionment percentage to taxable income. You will also review common error areas, including using the wrong state formula, inconsistent rounding, weighted formulas, and throwback considerations.