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Comparison of Stock Items and SKUs in TWICE inventory management

Inventory > Stock Items vs SKUs

TWICE Commerce uses two interconnected but distinct concepts for inventory management: Stock Items and SKUs. Understanding their relationship is essential for effective inventory management.

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Quick Comparison

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Stock Items

are the foundation of TWICE’s serialized inventory approach. Each stock item represents an individual physical unit that you track through its entire lifecycle.

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When to Use Stock Items

Track items individually when you need to know the specific history, condition, income, and expenses of each unit—essential for rental equipment, luxury goods, or assets.
When every unit is different (e.g., vintage clothing, used electronics, consignment items), each should be its own stock item.
Stock items maintain complete timelines, activity logs, and financial records for accountability and compliance.

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Stock Item Views

Navigate to Inventory > Stock Items to access:

General

Define identity, quantity, category, attributes, location, status, and media

Income & Expenses

Track individual item profitability with detailed income and expense records

Fulfillment

Configure checkout questions, service requirements, and preparation rules

Documents

Attach manuals, warranties, inspection reports, and certificates

Events

View past, present, and future events (orders, maintenance, transfers)

Activity Log

Complete audit trail of all changes and actions

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SKUs (Stock Keeping Units)

act as templates or wrappers that group similar stock items under a shared product definition. They streamline inventory management by defining information once and applying it to many items.

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When to Use SKUs

When you have multiple identical or similar items (e.g., 20 mountain bikes of the same model), create one SKU and link all items to it.
Define attributes, categories, and settings at the SKU level—all linked stock items inherit them automatically, eliminating repetitive data entry.Read more: How to Use SKUs to Streamline Inventory
View aggregated financial data, timelines, and documents across all items of a product type for performance analysis.
Link SKUs to catalog listings to ensure inventory availability flows correctly to your storefront.

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SKU Views

Navigate to Inventory > SKUs to access:

General

Define SKU identity, default settings, and basic product information

Attributes

Shared attributes inherited by all linked stock items

Stock Items

View and manage every stock item linked to this SKU

Documents

Manage shared documents that apply to all items (manuals, specifications)

Activity Log

Audit trail of SKU changes and aggregated item activities

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The Relationship

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How They Work Together

Define attributes on the SKU (e.g., “Brand: Atomic”, “Type: Ski”, “Size: Large”), and all linked stock items automatically inherit them. Update the SKU once, and all items reflect the change.
Even though stock items share a SKU, each maintains its own:
  • Unique item code and identity
  • Individual usage history and timeline
  • Separate income and expense records
  • Distinct condition and status
  • Own location and availability
The SKU provides consolidated views:
  • Total income and expenses across all items
  • Combined timeline of all events
  • Aggregated documents and activity logs
  • Product-level performance metrics
Each stock item can belong to one SKU at a time, maintaining a clear and traceable data structure.

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Common Scenarios

Scenario: You rent out 50 identical tents.Approach: Create one SKU “2-Person Tent” with shared attributes (brand, capacity, weight). Create 50 stock items, each representing a physical tent with its own serial number. Each tent’s rental history, maintenance, and condition are tracked individually, while the SKU provides fleet-level insights.
Scenario: Every item is unique with different brands, conditions, and prices.Approach: Use stock items for individual tracking. SKUs are optional but can still be useful for grouping (e.g., “Men’s Jackets” SKU with each jacket as a unique stock item having different sizes, brands, and conditions).
Scenario: Some items are serialized (high-value bikes), others are pooled (bike helmets).Approach: High-value bikes get individual stock items linked to a “Mountain Bike” SKU. For helmets, create one stock item with quantity > 1 for pooled tracking, linked to a “Bike Helmet” SKU.Read more: Inventory Tracking
Scenario: You want to display products on your online store with real-time availability.Approach: Create SKUs for each product type and link them to catalog listings. As stock items get booked or sold, availability automatically updates on your storefront.

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Key Takeaways

1

Stock Items are for tracking

Use stock items for individual, serialized tracking of physical units—each with its own lifecycle, financial records, and history.
2

SKUs are for grouping

Use SKUs as templates to group similar items, streamline data entry, and get product-level insights.
3

They work together

SKUs define shared information; stock items inherit it while maintaining individual tracking. This combination provides both efficiency and granularity.
4

Start with stock items

You can always create SKUs later to group items. Start by registering individual stock items, then organize them with SKUs as your inventory grows.

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Visibility and Permissions

Access to both Stock Items and SKUs is controlled by your . Your user role determines both and for , , and access levels.

Inventory Tracking

Learn about serialized vs. pooled inventory tracking methods

Stock Codes

Understand unique identifiers for stock items and their aggregation

Stock Item Status

Understand how to control operational availability of stock items

Stock Item State

Learn about automatic IN/OUT tracking for physical availability