Okla. Stat. tit. 46 § 44
In case of breach or default as determined by the terms of the mortgage, before the same may be used as a basis to foreclose the mortgage by power of sale, the mortgagee must give the mortgagor a written notice of intention to foreclose by power of sale by certified mail addressed to the mortgagor at the last-known address of the mortgagor. The notice shall state the name and address of the mortgagee, the nature of the breach(es) or default(s) claimed with reasonable specificity, that the mortgagor has a right for thirty-five (35) days from the date the notice is sent to cure a breach or default and thus to that extent reinstate the mortgage, the amount of money or action necessary to effect cure, that if the breach or default is not cured the mortgagee may accelerate the debt and give the notice provided for in Section 45 of this title or otherwise foreclose the mortgage, and that the notice contains important information concerning legal rights under the mortgage and Oklahoma law and that if the mortgagor has any questions an attorney should be promptly consulted. If a nonhomestead mortgagor is in default more than three (3) times in a twenty-four-month period and has been notified as provided for above, no right to an additional notice of intent to foreclose will be required prior to acceleration under Section 45 of this title. If a homestead mortgagor is in default more than four (4) times in a twenty-four-month period and has been notified as provided for above, no right to an additional notice of intent to foreclose will be required prior to acceleration under Section 45 of this title. If a mortgagee complies with a contractual provision for notice before acceleration in a Federal National Mortgage Association or Federal Home Loan Mortgage Corporation uniform instrument taken by the mortgagee which is substantially in compliance with or more stringent than the provisions of the notice of intention to foreclose by power of sale, such action by the mortgagee constitutes compliance with this section, but in any event, the requirements of this section shall run concurrently with any contractual provision for notice before acceleration in the mortgage. The notice of sale pursuant to Section 45 of this title may not be given or recorded until the provisions of this section are met.
Okla. Stat. tit. 46, § 44