Idaho Code § 50-1815
On or before the second Monday of July of each year in which the assessments are levied, the treasurer of the city shall enter all delinquent assessments and penalties on the assessment roll, which entry shall be considered to be dated as of the first day of July of each year, and shall have the force and effect of a sale to the city treasurer of the city as grantee in trust for said city of all the lands, parcels, pieces or tracts of real estate entered upon such assessment roll upon which such assessments have not been paid before delinquency. The penalty required to be added on delinquent assessments shall be two per cent (2%) of the amount unpaid and the treasurer of such city shall collect such assessments which are delinquent with such penalty added, together with interest on the amount of such delinquent assessment at the rate of eight per cent (8%) per annum from the date of sale until redemption.
Idaho Code § 50-1815