The difference between period costs and product costs is: Product costs are included in the balance sheet while period costs are displayed on the statement of cash flows. Period costs are the costs incurred making a product while product costs are the costs of sales and administration incurred within a defined time period. Product costs are the costs incurred to manufacture and distribute products while period costs and the costs of sales and administration within a defined time period Product costs are the costs incurred making a product while period costs are the costs of sales and administration incurred within a defined time period