OAR 150-317-1320: Estimated Tax: Unitary Groups and Apportioned Returns

(1) If two or more entities file a single Corporate Activity Tax (CAT) return as a unitary group, as described in ORS 317A.100(20), each shall be jointly and severally liable for the filing and payment of the estimated tax liability. Estimated tax payments shall be made on a combined basis. (2) See OAR 150-317-1310 for an explanation of how to compute an underpayment of estimated tax for entities filing a single CAT return as a unitary group. (3) Persons that are required to apportion the amount of the cost input or labor cost subtraction under ORS 317A.119 between Oregon and other states, are required to use either the current period’s actual or the prior full-year’s apportionment factor, as calculated under OAR 150-317-1200, to meet the annualization exception to underpayment of estimated taxes. The prior year’s apportionment factor may only be used if the prior year’s return covered a full 12 months.