When a product enters your warehouse, what happens to your accounts?

And when that same product leaves your warehouse after a sale, how does your accounting system know what changed?

For a business that sells physical products, these questions are more important than they may initially seem. A single inventory movement can affect stock quantities, inventory value, cost of goods sold, revenue, and financial records.

Imagine a printer distributor receiving a shipment of a few printers. The warehouse team needs to know how many printers arrived and where they are stored. At the same time, the accounting team needs accurate information about the value of that inventory. Later, when some of those printers are sold, the business needs to record the stock reduction, recognize the cost associated with the products sold, and account for the sales transaction.

This raises an interesting question:

Can inventory movements and accounting entries be connected automatically instead of being managed as completely separate processes?

This is where ERPNext’s inventory and accounting functionality becomes relevant.

When appropriately configured, ERPNext can connect applicable stock transactions with accounting entries. This allows businesses to maintain a relationship between what is physically happening to inventory and how those changes are represented financially.

But how does this actually work?

What happens when goods are received from a supplier? How is a Purchase Receipt different from a Purchase Invoice? What happens when products are delivered to customers? Where does COGS fit into the process? And how does Perpetual Inventory affect the way inventory is managed?

Let’s explore these concepts step by step.

What Happens When a Stock Transaction Takes Place?

An inventory transaction may appear simple from a warehouse perspective, but it can have several financial implications.

Suppose a business purchases 10 printers. From an operational perspective, the products arrive at the warehouse and become part of the company’s inventory. The stock quantity increases, and the business needs to record the value of the products received.

Later, if two of those printers are sold, the stock quantity decreases. The value associated with the outgoing inventory also needs to be considered, while the financial side of the sale is recorded separately.

This is where Cost of Goods Sold becomes relevant. COGS represents the direct cost associated with the products a business has sold to its customers.

For example, if a business purchases a printer for $500 and later sells it, the $500 cost associated with that printer contributes to the COGS of the sale. The amount charged to the customer is recorded as sales revenue.

As a result, a stock transaction can connect several areas of business operations:

Purchasing → Inventory → Stock Valuation → Sales → COGS → Accounting

The purpose of connecting these processes is to help maintain consistency between inventory records and financial records.

How Does ERPNext Connect Stock Transactions and Accounting?

ERPNext uses different documents and transactions to represent how inventory moves through a business.

Depending on the business process, products may be:

• Received from suppliers
• Stored in warehouses
• Transferred between locations
• Delivered to customers
• Adjusted after physical stock counts
• Moved for internal business requirements

When perpetual inventory accounting is enabled and properly configured, applicable stock transactions can have corresponding accounting impacts.

The general concept is that when inventory moves, the system can update the relevant stock information and record the associated accounting impact.

Several elements can influence how these transactions are handled, including:

• Company configuration
• Warehouse setup
• Item configuration
• Item Group configuration
• Stock accounts
• Valuation methods
• Valuation rates
• Accounting settings

This means ERPNext inventory accounting is not based on one isolated transaction. Instead, several connected components work together to represent the operational and financial aspects of inventory.

Perpetual vs Periodic Inventory: What Is the Difference?

One important concept to understand when discussing inventory accounting is Perpetual vs Periodic Inventory.

These are two different approaches to tracking and accounting for inventory.

What Is Perpetual Inventory?

A perpetual inventory system continuously updates inventory records as stock transactions take place.

When products are received, the inventory records are updated. When goods are delivered to customers, the stock position changes. Inventory movements can therefore be monitored throughout the accounting period.

For example, if a printer distributor receives new printers into a warehouse, the stock records can reflect the receipt. When some of those printers are later delivered to customers, the system can reflect the reduction in inventory.

A perpetual inventory approach can provide ongoing visibility into:

• Current stock quantities
• Warehouse-wise inventory
• Stock movements
• Inventory values
• Valuation rates
• Incoming and outgoing stock
• Cost of Goods Sold

This approach is particularly useful for businesses that handle frequent inventory transactions and require continuous information about their stock position.

What Is Periodic Inventory?

A periodic inventory system follows a different approach.

Instead of continuously updating inventory accounting with every stock movement, the business determines its inventory position at specific intervals.

This may happen monthly, quarterly, or annually, depending on the organization’s accounting practices.

Physical stock counting is generally important in a periodic inventory system because the business needs to determine the amount of inventory remaining at the end of the accounting period.

The business can then use this information to determine inventory-related costs and COGS for the period.

Periodic inventory may be suitable for smaller businesses or organizations with relatively simple inventory operations. However, it does not provide the same level of continuous inventory visibility as a perpetual inventory system.

Perpetual vs Periodic Inventory: Key Differences

 

Feature	Perpetual Inventory	Periodic Inventory
Stock updates	Continuously updated	Updated at specific intervals
Inventory visibility	Ongoing	Periodic
Stock valuation	Tracked continuously	Determined periodically
COGS	Associated with inventory movements	Determined at the end of the period
Physical stock count	Used for verification	Important for determining inventory
Inventory tracking	Detailed	Relatively simple
Suitable for	Frequent stock movements	Simpler inventory requirements

Understanding Perpetual vs Periodic Inventory is important when learning about ERP inventory accounting because it explains why businesses may choose different approaches to maintaining inventory information.

For organizations that need ongoing visibility into stock quantities and inventory values, a perpetual approach can provide more detailed information throughout the accounting period.

How Does the Purchase Process Work in ERPNext?

The purchase process in ERPNext can involve several stages, and each stage represents a different business event.

A typical purchasing process may begin with a Purchase Order, followed by a Purchase Receipt, and later a Purchase Invoice.

Although these documents are connected, they should not be treated as the same thing.

The Purchase Order represents the intention to purchase. The Purchase Receipt represents the physical receipt of goods. The Purchase Invoice represents the supplier’s bill.

Understanding these distinctions is important because the physical movement of inventory and the financial obligation to the supplier may not always happen at exactly the same time.

Purchase Order: Recording the Intention to Purchase

A Purchase Order records the business’s request to purchase products or services from a supplier.

It may include information such as:

• Supplier details
• Items
• Quantities
• Purchase prices
• Expected delivery dates
• Warehouse information

At this stage, the products may not yet be physically available in the warehouse.

The Purchase Order primarily represents the purchasing commitment or order placed with the supplier.

Purchase Receipt: Recording the Arrival of Inventory

When the supplier delivers the products, the business can record their receipt using a Purchase Receipt.

For example, a printer distributor may receive a shipment of printers at its warehouse. The Purchase Receipt records that the products have been received and allows the stock records to reflect the incoming inventory.

When perpetual inventory accounting is enabled, the receipt of inventory can also have an accounting impact based on the value of the stock received.

The exact accounting entries depend on the ERPNext configuration and the accounts associated with the transaction.

The important point is that the Purchase Receipt represents the physical receipt of goods, while the Purchase Invoice represents the financial document from the supplier.

Purchase Invoice: Recording the Supplier’s Bill

The Purchase Invoice records the supplier’s bill for the purchased goods or services.

This creates a distinction between two events:

Purchase Receipt: The business has received the goods.

Purchase Invoice: The supplier has submitted a bill for those goods.

For example, a company may receive a shipment of printers today but receive the supplier’s invoice later. By keeping these transactions separate, ERPNext can represent both the physical movement of inventory and the financial liability to the supplier.

How Does the Sales Process Work in ERPNext?

The sales process also involves multiple stages.

A typical process may include a Sales Order, followed by a Delivery Note, and then a Sales Invoice.

These documents represent different events in the sales cycle.

The Sales Order records what the customer has ordered. The Delivery Note records the physical movement of goods to the customer. The Sales Invoice records the financial side of the sale.

This separation helps distinguish between the operational and financial aspects of selling inventory.

Sales Order: Recording the Customer’s Order

A Sales Order records the customer’s requirement or confirmed order.

It may contain:

• Customer details
• Products
• Quantities
• Selling prices
• Delivery information

At this point, the products may still be physically present in the warehouse.

The Sales Order therefore represents the customer’s order rather than the actual movement of inventory.

Delivery Note: Recording the Outgoing Stock

When products are delivered to the customer, the business can create a Delivery Note.

For example, if a customer purchases two printers, the Delivery Note records the delivery of those products.

The stock quantity is reduced accordingly.

Under a perpetual inventory setup, the stock movement can also be connected with the relevant inventory accounting impact.

The value assigned to the outgoing inventory depends on the applicable stock valuation method.

Sales Invoice: Recording the Financial Transaction

The Sales Invoice represents the financial side of the sale.

It records the amount charged to the customer and may result in the recognition of sales revenue and an accounts receivable balance, depending on the payment terms.

This creates a clear distinction:

Delivery Note → Physical movement of products

Sales Invoice → Financial transaction

Both are important, but they represent different events in the sales process.

How Does COGS Relate to Inventory Accounting?

Cost of Goods Sold (COGS) is the direct cost associated with the products that a business has sold.

It is different from the selling price.

For example, a business may purchase a printer from a supplier and later sell it to a customer for a higher amount. The original cost of the printer contributes to COGS, while the amount charged to the customer represents sales revenue.

The difference between sales revenue and COGS contributes to the gross profit of the business before other operating expenses are considered.

In an inventory accounting system, the cost associated with products that have been sold moves from the inventory value to COGS.

This is why inventory valuation is important. The method used to determine the cost of outgoing inventory can influence the COGS recorded for a transaction.

How Does Stock Valuation Work in ERPNext?

Inventory has two important characteristics: its physical quantity and its financial value.

For example, a business may have several printers in a warehouse. The inventory system needs to track not only how many printers are available but also the value assigned to that stock.

Stock valuation helps determine the financial value of inventory as products enter and leave the business.

The valuation can depend on factors such as:

• Purchase costs
• Valuation method
• Valuation rate
• Previous stock transactions
• Inventory movements

ERPNext supports valuation methods such as FIFO and Moving Average, depending on the applicable configuration.

The selected valuation method can affect the value assigned to outgoing inventory and, consequently, the COGS associated with sales.

For this reason, businesses should consider their inventory management and accounting requirements when configuring stock valuation.

What Is the Role of the Stock Ledger?

The Stock Ledger provides a record of inventory movements within the system.

It can help users understand how stock quantities and values have changed over time.

For example, if a business wants to investigate why the stock of a particular printer model has changed, the Stock Ledger can help identify the transactions responsible for those changes.

It can provide information related to:

• Stock receipts
• Product deliveries
• Warehouse transfers
• Stock entries
• Inventory adjustments
• Valuation changes

The Stock Ledger can therefore be useful when reviewing inventory history or investigating discrepancies.

What Happens When Physical Stock and ERPNext Records Don’t Match?

Inventory discrepancies can happen even when a business has established inventory processes.

For example, the warehouse may physically contain 100 printers, while ERPNext shows 95.

There could be several reasons for this difference:

• Unrecorded sales
• Damaged products
• Incorrect stock entries
• Warehouse transfer errors
• Missing inventory
• Incorrect opening stock
• Data entry mistakes

The business should investigate the reason for the difference before making an adjustment.

ERPNext provides Stock Reconciliation functionality to help update inventory records when physical stock differs from the quantity recorded in the system.

However, reconciliation should ideally be supported by an investigation into the cause of the discrepancy. This can help businesses identify process issues and reduce the likelihood of repeated inventory differences.

Why Is the Connection Between Inventory and Accounting Important?

For businesses that manage physical products, inventory is both an operational resource and a financial asset.

Connecting inventory and accounting can help businesses maintain a clearer relationship between:

• Products received
• Products stored
• Products transferred
• Products sold
• Inventory value
• Cost of Goods Sold
• Sales revenue
• Supplier liabilities
• Customer receivables

This can be especially useful for businesses that handle frequent stock movements or operate multiple warehouses.

Consider a printer distributor that manages printers, cartridges, photo paper, consumables, and spare parts across different locations. The business needs to know not only what is available in each warehouse but also how inventory movements affect the financial records.

By connecting these processes, ERPNext can provide a more integrated view of inventory and accounting.

Understanding the Complete Stock-to-Accounting Process in ERPNext

The connection between inventory and accounting becomes clearer when the entire business process is viewed as one continuous cycle.

The process begins when a business decides to purchase products. A Purchase Order records the planned purchase, but the inventory itself does not necessarily change at this stage. When the products physically arrive at the warehouse, the business records a Purchase Receipt. This is the point at which the incoming stock becomes part of the inventory records.

Once the supplier’s bill is received, the Purchase Invoice records the financial obligation associated with the purchase. This creates a connection between the products that have entered the warehouse and the amount the business owes to the supplier.

The process works similarly on the sales side. A Sales Order records the customer’s requirement, but the stock remains in the warehouse until the products are actually delivered. When the goods leave the warehouse, the Delivery Note records the physical stock movement. Under a perpetual inventory setup, the value associated with the outgoing inventory can also be reflected in the relevant accounting process, including COGS.

The Sales Invoice then records the financial side of the transaction. It represents the amount charged to the customer and can create a receivable when the customer has not yet paid.

Therefore, the complete process can be understood as a series of connected business events rather than one single transaction.

On the purchasing side:

The business places an order, receives the products, updates its inventory, and records the supplier’s invoice. These steps collectively represent both the operational and financial aspects of acquiring stock.

On the sales side:

The customer places an order, the products are delivered, inventory is reduced, the cost associated with the products sold is recognized, and the financial sale is recorded.

This connected approach allows businesses to follow a product from the moment it enters the warehouse to the moment it leaves as part of a customer sale. It also helps explain how inventory movements, stock valuation, COGS, revenue, payables, and receivables can be related within an ERP environment.

The exact accounting entries and workflow depend on the company’s configuration, valuation settings, accounts, and business processes in ERPNext.

Frequently Asked Questions

1. What is COGS in ERPNext?

COGS stands for Cost of Goods Sold. It represents the direct cost associated with products sold by a business. In inventory accounting, the cost associated with products sold is transferred from inventory to COGS.

2. What is the difference between Perpetual and Periodic Inventory?

Perpetual inventory continuously tracks inventory movements and updates inventory records as transactions occur. Periodic inventory determines inventory levels and inventory-related costs at specific intervals, generally with the help of physical stock counts.

3. Does ERPNext support perpetual inventory?

Yes. ERPNext supports perpetual inventory accounting, allowing applicable stock transactions to have corresponding accounting impacts when the relevant configuration is enabled.

4. What is the difference between a Purchase Receipt and Purchase Invoice?

A Purchase Receipt records the receipt of goods into inventory, while a Purchase Invoice records the supplier’s bill and corresponding financial liability.

5. What is the difference between a Delivery Note and Sales Invoice?

A Delivery Note records the physical delivery of products, while a Sales Invoice records the financial transaction associated with the sale.

6. What is stock valuation?

Stock valuation refers to determining the financial value assigned to inventory. The valuation method can influence the cost assigned to outgoing stock and the COGS associated with sales.

7. What is the Stock Ledger used for?

The Stock Ledger records inventory movements and helps businesses review changes in stock quantities and values over time.

8. Why can physical stock differ from ERPNext stock?

Differences can occur because of unrecorded transactions, damaged products, incorrect stock entries, warehouse transfer errors, missing stock, or incorrect opening balances.

Conclusion

Inventory accounting involves more than simply tracking the number of products available in a warehouse. Every purchase, receipt, transfer, and sale can affect both the physical inventory and the financial records of a business.

ERPNext connects these areas through its inventory and accounting functionality. Understanding how Purchase Orders, Purchase Receipts, Purchase Invoices, Sales Orders, Delivery Notes, and Sales Invoices work together provides a clearer picture of how products move through an ERP system and how those movements can affect financial records.

The concept of Perpetual vs Periodic Inventory is also important when learning about inventory accounting. Perpetual inventory provides continuous visibility into stock movements and inventory values, while periodic inventory relies more heavily on periodic stock counts and end-of-period calculations.

For businesses using ERPNext, proper configuration of companies, warehouses, items, valuation methods, and accounting settings is essential for maintaining accurate records. A connected inventory and accounting process can help businesses understand their stock position while maintaining better visibility into the financial impact of inventory transactions.

KyleSolutions, one of the leading business solution providers in Calicut and across Kerala, helps businesses explore technology and business solutions that can support more efficient digital processes and day-to-day operations.