Unique Serial Numbers (USN) – Serialized Inventory Handling

Unique Serial Numbers (USN) – Serialized Inventory Handling

InfoSoftware Plan: Growth & Enterprise
InfoAccount Type: Seller Account / 3PL
InfoInventory Type: Serialized Inventory
USN configurations are enabled at the account level by the Easyecom team.

Overview

Unique Serial Numbers (USN) is a configuration used to manage serialized inventory in Easyecom.
When USN is enabled, each unit of a serialized SKU is tracked using a unique serial number. These serial numbers are validated during inventory inward and stored against the inventory unit.
USN configuration determines how serial numbers are generated or captured during inventory inward operations.
Serialized inventory must be enabled for the SKU before USN workflows apply.

Visual Overview of USN Workflow


This diagram illustrates how serialized inventory and USN configuration work together and how different USN types handle serial numbers during inventory inward.
It also illustrates how different USN types capture or generate serial numbers during inventory inward.

When to Use This Feature

Use USN when inventory must be tracked at the individual unit level using serial numbers.
Typical scenarios include:
  • Products where each unit has a unique serial number
  • Inventory requiring unit-level traceability
  • Serialised tracking or warranty tracked products
  • Inventory requiring unit level validation during inward

Operational Context

Serialized inventory and USN configuration work together.

ConfigurationPurpose
Serialized InventoryEnables serial tracking for a SKU
USN ConfigurationDefines how serial numbers are generated or captured

Serialized inventory must be enabled for the SKU before USN workflows apply.

Operational Scenarios for USN Categories

USN configurations are grouped into two categories based on who generates the serial numbers.

Category 1 – Seller Provides Serial Numbers

In this configuration, serial numbers are already assigned to products by the manufacturer or vendor.
The seller must provide these serial numbers during inventory inward.
System behavior:
  • Easyecom validates the serial numbers provided by the seller.
  • Serial numbers are stored and mapped to inventory units.
  • Easyecom does not generate serial numbers.
Typical use cases:
  • electronics with manufacturer serial numbers
  • warranty-tracked products
  • products where serial numbers are printed by the manufacturer
USN Types in this category:
  • USN Type 1
  • USN Type 2

Category 2 – Easyecom Generates Serial Numbers

In this configuration, serial numbers are generated by Easyecom.
The seller does not receive serial numbers from the vendor.
System behavior:
  • serial numbers are generated within Easyecom
  • barcode labels may be generated for scanning during inward
  • serial numbers are mapped to inventory units
Typical use cases:
  • products without manufacturer serial numbers
  • warehouse-generated barcode systems
  • internal asset tracking
USN Types in this category:
  • USN Type 3
  • USN Type 4
  • USN Type 5

USN Type Comparison

USN TypeSerial SourceCapture StageAuto GRNPO Creation
Type 1SellerPO CreationNot SupportedAPI Only
Type 2SellerGRNSupportedUI/API/Sheet
Type 3EasyecomAfter PO CreationNot SupportedUI/API/Sheet
Type 4EasyecomAfter GRNSupportedUI/API/Sheet
Type 5EasyecomBarcode ScreenDependsUI/API/Sheet

Identify Your USN Configuration

Different Easyecom accounts may operate using different USN configurations.

You can identify the configuration based on how serial numbers are handled during inventory inward.

Observed BehaviorLikely USN Type
Serial numbers must be provided during Purchase Order creation via APIUSN Type 1
Serial numbers are provided or scanned during GRNUSN Type 2
Serial barcodes are generated from the Purchase Order pageUSN Type 3
Serial numbers are generated automatically after GRNUSN Type 4
Serial numbers are generated from a barcode generation screenUSN Type 5

If the configuration is unclear, contact the Easyecom Support team.

Navigation

The following screens are used during serialized inventory inward.

ActivityNavigation
View Purchase OrdersInventory → Purchase Orders
Generate serial barcodesPurchase Orders → View Details → Generate Barcode
View generated serial numbersPurchase Orders → View Details → Serial Outward
Create GRNInventory → GRN → New GRN

USN Configuration Types

USN configurations define how serial numbers are generated or captured during inventory inward.

USN Type 1 – Serial Numbers Provided During PO Creation (API)

In this configuration, serial numbers must be provided when creating the purchase order through API.
System behavior:
  • Serial numbers are entered during PO creation.
  • Serial numbers are stored and validated during GRN.
  • Serial numbers cannot be generated automatically by the system.
  • Auto GRN is not supported.
Serial numbers may be provided using supported integrations such as API.
Workflow:
  1. Create Purchase Order and Provide Serial Numbers for each SKU in the API Request

    create a PO by putting serial numbers via API Create Purchase Order

    {
        "vendorId": "VENDORE123",
        "referenceCode": "TestPo22232",
        "address": "Mumbai ",
        "expDeliveryDate": "2025-07-20",
        "shippingCost": 0,
        "createOrUpdate": "I",
        "isCancel": 0,
        "docNumber": "12",
        "updateTaxRate": 1,
        "items": [
            {
                "lineItemNumber": "12",
                "sku": "SODA01",
                "quantity": "3",
                "unitPrice": 5,
                "taxRate": "18",
                "taxValue": 3.8,
                "taxType": 1,
                "batch_code": "secfgv453456",
                "batch_mrp": "342",
                "expiry_date": "2036-01-12",
                "serials": [
                    "UK07812",
                    "UK08912",
                    "UK09012"
                ]
            }
        ]
    }
    As demonstrated in the example above, you must provide the exact number of serial numbers as the quantity specified in the API.

  2. Purchase Orde created using API is created in Approved Status.


  3. Click View Details and from Hamburger Menu, Download USN Report




  4. Perform GRN


  5. System validates serial numbers

USN Type 2 – Serial Numbers Provided During GRN

In this configuration, serial numbers are captured during inventory inward.
System behavior:
  • Purchase orders are created without serial numbers.
  • Serial numbers are entered or scanned during GRN.
  • Serial numbers are validated during inward.
  • Serial numbers are stored after validation.
Auto GRN is supported.

Workflow:

  1. Create Purchase Order (Manual/Sheet/API) and find it in Inventory > Purchase Orders tab.
    Apply Required Filters to find the PO.

  2. Click on View Details → GRN

  3. Create new GRN against the purchase order.
    Click on New GRN > Enter Invoice Details / upload later > Proceed

  4. Scan or enter serial numbers for the SKU.

  5. Enter All details and Click Save to Complete GRN (Proceed to Confirm)


    If required, Click on 3 Dots option on right side of GRN, to Download all Barcodes 

USN Type 3 – Serial Numbers Generated After PO Creation

In this configuration, serial numbers are generated after the purchase order is created.
Serial barcodes are generated from the Purchase Order screen and used during GRN.
System behavior:
  • Purchase order is created first.
  • Serial barcodes are generated from the purchase order page.
  • Serial numbers must be scanned during GRN.
  • Auto GRN is not supported.
Workflow

Step 1
Create the Purchase Order (Manual/Sheet/API)


Step 2
Navigate to:

Inventory → Purchase Orders

Step 3
Select the required date range and purchase order status.


Step 4
Click View Details for the purchase order.

Step 5
Enter the Barcode Quantity to Print.


Step 6
Click the Hamburger Menu.

Select Generate Barcode.


The system generates serial barcodes for the purchase order.


Step 7
To view generated serial numbers:

Click Hamburger Menu → Serial Outward


Step 8
Perform GRN.

Click on New GRN

Add the SKU and scan the serial numbers.


Step 9
Fill the required GRN details and save.

If required, GRN Screen can be configured/updated beforehand. To learn more click How to Configure GRN Screen

Provide confirmation that the entered details are correct and proceed.


Important:
During GRN, scanning the serial number automatically fetches the corresponding SKU and purchase order details.
For additional information on serialized inward behavior, refer to:
USN – Unique Serial Numbers

USN Type 4 – Serial Numbers Generated After GRN

In this configuration, serial numbers are generated automatically after inventory inward.
System behavior:
  • Seller provides SKU and quantity during GRN.
  • Serial numbers are generated automatically by the system.
  • Generated serial numbers are mapped to the inwarded inventory.
  • Barcode labels can be generated for the created serial numbers.
Auto GRN is supported.
Workflow:
  1. Create Purchase Order (Manual/Sheet/API)


  2. Click View Details > GRN > New GRN to Perform GRN.


  3. Enter SKU and quantity.


  4. System generates serial numbers automatically.

  5. Serial numbers are mapped to inwarded inventory.

USN Type 5 – Serial Numbers Generated From Barcode Screen

In this configuration, serial numbers are generated from a barcode generation screen.
System behavior:
  • Serial numbers are generated from the barcode generation interface.
  • During GRN, both SKU and serial numbers are scanned.
  • The system validates the serial numbers and maps them to the SKU inventory.
The workflow may vary depending on the configuration enabled for the account.

Workflow:
  1. Generate serial numbers from the barcode generation screen.

  2. For a Created & Approved PO, Perform GRN.







  3. Scan SKU and serial numbers.


  4. System validates serial numbers and maps them to inventory.

System Behavior During GRN

When serialized inventory is inwarded:
  • serial numbers are validated before GRN is completed
  • each serial number must be unique
  • duplicate serial numbers cannot be inwarded
  • serial numbers remain permanently mapped to the inventory unit
Additional prompts may appear depending on account configuration, such as:
  • Good / Bad inventory selection
  • bin scanning during putaway
  • QC fail reason selection

Operational Rules

  • Each serialized inventory unit must have a unique serial number.
  • Duplicate serial numbers cannot be inwarded.
  • Serial numbers cannot be edited after inward.
  • Serial numbers remain associated with the inventory unit until consumed through order processing.

Outcome

After successful inward:
  • serial numbers are mapped to individual inventory units
  • each unit can be tracked using its serial number
  • serial information remains available for inventory tracking and order processing

FAQs

Can serial numbers be edited after GRN?
No. Serial numbers remain permanently associated with the inventory unit after inward.
Can Auto GRN be used with serialized inventory?
Auto GRN availability depends on the configured USN type.
Some configurations require serial scanning during GRN.
Can serial numbers be generated automatically?
Yes. Certain USN configurations generate serial numbers automatically through the system.

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