Multistate corporations apportion income on a water's edge basis using the standard apportionment formula of property, payroll and sales. Oil and gas corporations use a modified apportionment formula applied to worldwide income.
Tax payment is due two and one half months from the close of the tax year.
The payment due date cannot be extended. Tax returns are due three and one-half months after the close of the tax year. More information on corporate net income tax is in the division's FY 2000 annual report.