Okla. Stat. tit. 11, § 11-17-215

Limitations on encumbrances or expenditures.

A. The chief executive officer, or designee, as authorized by

the governing body, may transfer any unexpended and unencumbered

appropriation or any portion thereof from one department to another

within the same fund; except that no appropriation for debt service

or other appropriation required by law or ordinance may be reduced

below the minimums required.

B. Any fund balance in an enterprise fund of the municipality

may be transferred to another fund of the municipality as authorized

by the governing body. Other interfund transfers may be made only

as adopted or amended according to Section 17-206 or 17-216 of this

title.

C. Whenever the necessity for maintaining any fund of a

municipality has ceased to exist and a balance remains in the fund,

the governing body may authorize the transfer of the balance to the

general fund or any other designated fund, unless otherwise provided

by law.

D. No encumbrance or expenditure may be authorized or made by

any officer or employee which exceeds the available appropriation

for each department within a fund.

Oklahoma Statutes - Title 11. Cities and Towns Page 127