Idaho Code § 43-708
On or before the second Monday of January of each year succeeding the year in which the assessments are levied the treasurer shall carry out and enter all delinquent assessments, with the penalties thereon, on the assessment roll, which entry shall be considered to be dated as of the first day of January in such succeeding year, and shall have the force and effect of a sale to the treasurer of the district as grantee in trust for the district for all lands entered upon the assessment roll upon which one-half (1/2) or more of the original amount of such assessments have not been paid before delinquency.
On or before the second Monday of July of such succeeding year the treasurer shall make delinquency entries as hereinbefore described for all lands entered on the assessment roll on which the remaining one-half (1/2) of the original amount of such assessment has not been paid before delinquency, which entries shall also be considered to be dated as of January first of such year.
The penalties required to be added on delinquent assessments shall be two per cent (2%) of the amount remaining unpaid and the treasurer shall collect such delinquent assessments with such penalty added, together with interest on the amount of such delinquent assessments at the rate of one per cent (1%) per month from said first day of January until redemption, provided that where such penalties and interest do not aggregate the sum of one dollar ($1.00) on any one assessment number, the treasurer shall not be required to collect such penalty and interest.
Provided, that if the first half (1/2) of such taxes be not paid prior to the said twentieth day of December, the amount of such one-half (1/2), plus a penalty of two per cent (2%) thereof with interest on the total at the rate of one per cent (1%) per month from the date of delinquency may be paid at any time between the third Monday of January in the year succeeding the year in which such taxes are levied and the twentieth day of June next thereafter, and, in the event of such payment, the second one-half (1/2) of such taxes may be paid thereafter, without penalty, at any time between the two (2) dates last above-mentioned.
Idaho Code § 43-708