Start with beginning inventory
Add purchases made during the period
Add direct costs related to production or acquisition
Subtract ending inventory
Use the formula: COGS = Beginning Inventory + Purchases + Direct Costs – Ending Inventory
For manufacturers, use: COGS = Beginning Finished Goods Inventory + Cost of Goods Manufactured – Ending Finished Goods Inventory
For retailers, use: COGS = Beginning Inventory + Net Purchases – Ending Inventory
For service businesses, use direct labor and direct service costs instead of inventory-based costs
