To which organizational level do you have to assign the valuation area to create material costings?

The controlling area is an organizational unit for management accounting and cost controlling, but it is not the direct organizational level for defining material valuation or for executing material costing.

While a company code can be chosen as a valuation area in some limited scenarios, for material costing, the plant is the standard and required valuation area to determine the cost of goods manufactured.

A business area is an organizational unit for internal segment reporting and does not serve as a valuation area for material costing.

In SAP, the valuation area is either a plant or a company code, but for material costing and typical manufacturing/inventory scenarios, the plant is the mandatory organizational level. All materials in a plant are valuated consistently within that plant, and costing runs are performed at the plant level.