First in, first out method (FIFO)

Overview of the First-in, First-out Method

The first in, first out (FIFO) method of inventory valuation is a cost flow assumption that the first goods purchased are also the first goods sold. In most companies, this assumption closely matches the actual flow of goods, and so is considered the most theoretically correct inventory valuation method. The FIFO flow concept is a logical one for a business to follow, since selling off the oldest goods first reduces the risk of obsolescence.

Under the FIFO method, the earliest goods purchased are the first ones removed from the inventory account. This results in the remaining items in inventory being accounted for at the most recently incurred costs, so that the inventory asset recorded on the balance sheet contains costs quite close to the most recent costs that could be obtained in the marketplace. Conversely, this method also results in older historical costs being matched against current revenues and recorded in the cost of goods sold; this means that the gross margin does not necessarily reflect a proper matching of revenues and costs. For example, in an inflationary environment, current-cost revenue dollars will be matched against older and lower-cost inventory items, which yields the highest possible gross margin.

The FIFO method is allowed under both Generally Accepted Accounting Principles and International Financial Reporting Standards. The FIFO method provides the same results under either the periodic or perpetual inventory system.

Example of the First-in, First-out Method

Milagro Corporation decides to use the FIFO method for the month of January. During that month, it records the following transactions:

Unit Cost
Total Cost
  +100 $210 $21,000
Sale -75    
Purchase (layer 2) +150 280 42,000
Sale -100    
Purchase (layer 3) +50 300 15,000
Ending inventory = 125    

The cost of goods sold in units is calculated as:

100 Beginning inventory + 200 Purchased – 125 Ending inventory = 175 Units

Milagro’s controller uses the information in the preceding table to calculate the cost of goods sold for January, as well as the cost of the inventory balance as of the end of January.

  Units Unit Cost Total Cost
Cost of goods sold      
   FIFO layer 1 100 $210 $21,000
   FIFO layer 2 75 280 21,000
  175   $42,000
 Ending inventory      
   FIFO layer 2 75 280 $21,000
   FIFO layer 3 50 300 15,000
  125   $36,000

Thus, the first FIFO layer, which was the beginning inventory layer, is completely used up during the month, as well as half of Layer 2, leaving half of Layer 2 and all of Layer 3 to be the sole components of the ending inventory.

Note that the $42,000 cost of goods sold and $36,000 ending inventory equals the $78,000 combined total of beginning inventory and purchases during the month.