Perpetual and Periodic Inventory Record Systems

When it comes to managing inventory, businesses have two primary methods: perpetual inventory record system and periodic inventory record system. Understanding the difference between these two approaches is crucial for effective inventory management. Let’s delve into the concepts of perpetual and periodic inventory record systems and explore how they work.

Perpetual Inventory Record System: 

The perpetual inventory record system is a real-time method of tracking inventory levels. It relies on technology, such as barcode scanners and inventory management software, to keep a continuous and updated record of every inventory transaction. With this system, inventory levels are automatically adjusted with each purchase, sale, or return.

How does it work? 

Let’s consider an example: A retail store using a perpetual inventory record system for its clothing inventory. Each garment has a unique barcode. When a customer purchases an item, the barcode is scanned, and the software deducts the sold quantity from the inventory count in real-time. Similarly, when new stock arrives, it is scanned and added to the inventory count instantly. This enables the business to have accurate, up-to-date information on inventory levels at any given moment.

Benefits of perpetual inventory record system:

  1. Real-time visibility: Businesses can have a precise understanding of inventory levels at any time, minimizing the risk of stockouts or overstocking.
  2. Efficient order management: With real-time information, businesses can quickly identify low inventory levels and replenish stock accordingly.
  3. Accurate financial reporting: The perpetual inventory record system provides accurate data for financial statements, including cost of goods sold (COGS) and ending inventory.

Periodic Inventory Record System: 

In contrast, the periodic inventory record system takes a periodic or intermittent approach to update inventory levels. Rather than continuously tracking inventory, businesses conduct physical counts at specific intervals to determine the quantity on hand. The frequency of physical counts can vary based on the business’s needs but is typically done monthly, quarterly, or annually.

How does it work? 

Let’s continue with the clothing retail store example. In a periodic inventory record system, the store would conduct physical inventory counts, say, at the end of each month. During the count, all items in stock are tallied manually or using handheld devices, and the inventory count is adjusted accordingly.

Benefits of periodic inventory record system:

  1. Simplicity: The periodic system requires fewer resources and technology compared to a perpetual system, making it easier to implement for smaller businesses.
  2. Cost-effective: Conducting physical counts periodically reduces the need for sophisticated inventory management software and barcode scanners.
  3. Practical for certain industries: Industries with lower inventory turnover or businesses dealing with expensive or unique items may find periodic inventory counts more practical.

Choosing the Right System: 

Selecting the appropriate inventory record system depends on various factors such as the size of the business, industry requirements, inventory turnover rate, and available resources. Many businesses opt for a perpetual inventory record system due to its real-time tracking capabilities, accuracy, and efficiency. However, smaller businesses with lower inventory levels or specialized items may find periodic inventory record systems sufficient for their needs.


Understanding the distinctions between perpetual and periodic inventory record systems is essential for effective inventory management. Assess your business requirements, industry demands, and available resources to determine the most suitable approach to monitor and control your inventory effectively.