Opening Inventory Formula / Equation

Opening Inventory is closing inventory of previous accounting period. So, it is the opening balance of the new current accounting period. It is calculated by adding Cost of Sales to Closing Inventory and subtracting  Net Purchases.

Mathematically, we can use the below Opening Inventory Formula or Equation:

Opening Inventory = (Cost of Sales + Closing Inventory) - Net Purchases

Opening Inventory is shown on Income Statement or Trading Account of the current accounting period.