Okla. Stat. tit. 68, § 68-2385.13: Amount of estimate - Penalty for underestimating

A. In the case of any underpayment of the estimated tax payment

required in Section 2385.9 of this title, there shall be added to

the amount of the underpayment interest thereon at an annual rate of

twenty percent (20%) for the period of the underpayment.

B. As used in subsection A of this section, the amount of the

underpayment shall be the excess of the required installment over

the amount paid on or before the due date of the installment. The

period of underpayment shall run from the due date of the required

installment to the earlier of the fifteenth day of the fourth month,

or for corporations, thirty (30) days after the due date for returns

established under the Internal Revenue Code, following the close of

the taxable year or the date on which the required installment is

paid.

C. No addition to tax shall be imposed under subsection A of

this section if the tax shown on the return for the taxable year is

less than One Thousand Dollars ($1,000.00) or if the taxpayer was an

Oklahoma resident throughout the preceding taxable year of twelve

(12) months and did not have any liability for tax for the preceding

taxable year.