Since the annual budget is formulated well in advance of its execution, the Board of County Commissioners recognizes that it may be necessary to amend the budget. If unexpected or unfunded expenditures must be made, Officials and Directors are expected to manage their available resources, economize, and reevaluate priorities before requesting a budget adjustment.

A supplemental budget appropriation is most often required when new appropriation authority is needed. For example, a department may receive revenue they did not plan for in their budget that they would like to spend in the current fiscal year, or an urgent situation may require unanticipated expense.

Although a supplemental budget is usually associated with the expenditure of new appropriations and increased revenues, it can also be used for other purposes. For example, a supplemental budget is usually required to create a new fund during the fiscal year or when transferring appropriation authority from item categories to the personnel budget categories.