Can the Cost of Goods Sold be considered a mixed cost?

No, the cost of goods sold is calculated by one type of expense. That expense is the cost to purchase raw material to assemble products sold to customers.

By defining what mixed costs are, will demonstrate why the answer is no. Mixed costs are those costs associated with both fixed and variable attributes. An example would be the costs involved in owning farming equipment.

Fixed costs would be the machinery's depreciation expenses and the variable costs are the expenses involved with expected and unexpected equipment maintenance.

This example shows that Cost of goods sold can't be a mixed cost because it has just one expense involved, not two.