Okla. Stat. tit. 11, § 11-37-222

Assessments in conformity with the appraisement and

apportionment, as corrected and confirmed by the governing body,

shall be payable in ten equal annual installments, and shall bear

interest not to exceed the rate of thirteen percent (13%) per annum

until paid, payable in each year at such time as the several

installments are made payable. The governing body, by ordinance and

by referring to the assessment roll as confirmed, shall levy

assessments in accordance with the assessment roll and

apportionment, as confirmed, against the several lots and tracts of

land liable therefor. The ordinance shall provide that the owners

of the property so assessed shall have the privilege of paying the

amounts of their respective assessments without interest within

thirty (30) days after the date of the publication of the assessing

ordinance. The special assessments, and each installment thereof

and the interest and penalties thereon, are hereby declared to be a

lien against the lots and tracts of land as assessed from the date

of the publication of the ordinance levying the same, coequal with

the lien of other taxes and prior and superior to all other liens

against such lots or tracts of land. The liens shall continue as to

unpaid installments, interest and penalties until the assessments,

interest and penalties thereon shall be fully paid, but unmatured

installments shall not be deemed to be within the terms of any

general convenant or warranty.