If property taxes are not paid for any reason within thirty days after the date they are due, interest on the unpaid taxes shall accrue from the thirtieth day after they are due until the date they are paid. Interest shall accrue at the rate of one percent a month or any fraction of a month. Interest shall accrue whether or not protests have been resolved. However, in the case of a timely protest, interest payable shall be computed on a principal amount equal to the unpaid taxes finally determined to be due upon resolution of the protest. Interest shall not be imposed on interest or on any penalty.
NMS § 7-38-49