Idaho Code § 63-3504
Upon receipt of the notification of the allotment and apportionment of such taxes by the state tax commission by the county treasurer, said county treasurer shall, not later than June 15 of each year, notify each cooperative electrical association, natural gas cooperative, and producer of electricity by means of wind energy, by means of solar energy or by means of geothermal energy, of the amount of taxes owed, and the apportionment thereof to the county and to the several taxing districts in the county and such tax shall be due and payable not later than July 1, following and, upon the payment thereof, the county treasurer shall pay over to each taxing district its apportionment as herein determined. Any such taxes not paid by July 1, as aforesaid, shall become delinquent and a penalty of five percent (5%) thereof shall be imposed, together with interest at the rate of one percent (1%) per month from July 1 until paid.
Idaho Code § 63-3504