In the state of Oklahoma, there is a $5 certification fee charged to file the Mortgage Affidavit.
In LodeStar's Calculator, within Section E, this fee is listed as "County - Mortgage Tax". We bundle this fee into the mortgage tax section rather than a recording fee because it is directly related to the mortgage tax calculation / exemption amounts:
For more information, please consult:
https://www2.tulsacounty.org/treasurer/payments/mortgage-tax-calculator/