Okla. Stat. tit. 6, § 6-1016: Service charges not part of interest on loans

The charges or service fees made by the trust department of any

bank having trust powers and of any trust company organized and

existing under the laws of this state, for any services performed or

under any powers granted to such company, under the laws of this

state, shall not be considered any part of the interest charged on

any loan and shall not be subject to the interest laws of the state.