1.    Except as permitted under subsections 2 through 4, all business income must be apportioned to this state by multiplying the income by a fraction, the numerator of which is the property factor plus the payroll factor plus the sales factor, and the denominator of which is three.

2.    For the first two taxable years beginning after December 31, 2015, a taxpayer that is not a passthrough entity may elect to apportion business income to this state by multiplying the income by a fraction, the numerator of which is the property factor plus the payroll factor plus two times the sales factor, and the denominator of which is four. a.    The election must be made on the return as originally and timely filed in the form and manner prescribed by the tax commissioner.

b.    The election is applicable for all companies in a unitary group and for all companies filing a consolidated North Dakota return.

c.    The election is binding for five consecutive taxable years after making the election, at which time the election lapses. The election under this subsection     also includes the election to use the sales factor under subsections 3 and 4 for the taxable years those subsections apply.

d.    Unless a taxpayer makes another election under subsection 4 in the taxable year immediately following the final year of the binding effect of the election under this subsection, the taxpayer must file under subsection 1 for a period of three taxable years before it may make a new election under subsection 4.

3.    For the first taxable year beginning after December 31, 2017, a taxpayer that is not a passthrough entity may elect to apportion business income to this state by multiplying the income by a fraction, the numerator of which is the property factor plus the payroll factor plus six times the sales factor, and the denominator of which is eight.

a.    The election must be made on the return as originally and timely filed in the form and manner prescribed by the tax commissioner.

b.    The election is applicable for all companies in a unitary group and for all companies filing a consolidated North Dakota return.

c.    The election is binding for five consecutive taxable years after making the election, at which time the election lapses. The election under this subsection also includes the election to use the sales factor under subsection 4 for the taxable years that subsection applies.

d.    Unless a taxpayer makes another election under subsection 4 in the taxable year immediately following the final year of the binding effect of the election under this subsection, the taxpayer must file under subsection 1 for a period of three taxable years before it may make a new election under subsection 4.

4.    For taxable years beginning after December 31, 2018, a taxpayer that is not a passthrough entity may elect to apportion business income to this state by multiplying the income by the sales factor. A taxpayer electing to file using a single sales factor must comply with the following:

a.    The election must be made on the return as originally and timely filed in the form and manner prescribed by the tax commissioner.

b.    The election is applicable for all companies in a unitary group and for all companies filing a consolidated North Dakota return.

c.    The election is binding for five consecutive taxable years after making the election, at which time the election lapses.

d.    Unless a taxpayer makes another election under this subsection in the taxable year immediately following the final year of a prior single sales factor election, the taxpayer must file under subsection 1 for a period of three taxable years before it may make a new single sales factor election.