Ariz. Rev. Stat. § 35-151 – Encumbrance documents; issuance and disposition; exception

A. An encumbrance document shall be processed in this state's accounting system before a budget unit issues a purchase order or encumbrance document against appropriations to cover an obligation, actual or anticipated, except that encumbrance documents are not required for:
1. 1. Reimbursements to employees for travel or other expenses incurred.
2. 2. Gross payrolls and related employee expenses of a budget unit.
3. 3. Eligibility payments.
4. 4. Required payments that are not discretionary.
5. 5. Under procedures prescribed in the state accounting manual of the department of administration, expenditures not exceeding $5,000.
B. Copies of the encumbrance documents shall be submitted immediately to or entered into the state accounting system of the department of administration. The budget unit shall certify that the proposed expenditure is authorized by appropriation and allotment and that the amount involved does not exceed the unencumbered and unexpended balance of the appropriation as recorded in the state's accounting system. If any proposed certified expenditure is found to exceed the unencumbered and unexpended balance or to be contrary to this chapter or any other law, the head of the budget unit or the head's designee shall disallow the proposed expenditure. If the encumbrance is found to be in order, it shall be immediately submitted or electronically transmitted to the department of administration central accounting system, which shall not accept an encumbrance in excess of the appropriation. The amount of the encumbrance shall be set aside to be used exclusively to pay the claim when presented. If an adequate appropriation balance is not available, the accounting system shall reject the transaction.
C. The department of administration may require encumbrances for all funds of this state, except for the investment of public monies or permanent endowment funds, which are not appropriated but are held in custody by the state treasurer.
D. An encumbrance document may not be approved by or for any budget unit that will involve an expenditure of any amount in excess of the unencumbered and unexpended balance of the appropriation or fund source to which the resulting expenditure will be chargeable.
E. Except for an expenditure that is exempt under subsection A of this section, an expenditure under section 35-191 shall be encumbered regardless of the dollar amount of the expenditure.