Curvilinear costs are characterized by:

Curvilinear costs are defined by their non-linear behavior, which means that as production levels change, the cost does not increase or decrease in a straight line. Instead, curvilinear costs can rise at varying rates as production increases, reflecting how resources may be consumed differently at different production levels. This non-linear behavior recognizes that costs may exhibit increasing or decreasing marginal cost behaviors depending on the scale of operations or other factors.

For example, in manufacturing, initial increases in production may lead to lower average costs due to economies of scale, while beyond a certain point, costs may start to increase at an accelerating rate due to factors like overtime pay or the need for more expensive resources as capacity constraints are reached. This behavior contrasts with other types of costs; fixed costs remain constant regardless of production levels, while variable costs usually change proportionally, and linear relationships are characterized by a consistent rate of change, neither of which describes curvilinear costs accurately.