Table of Contents
October 9, 2025
. 6 min

SKU vs UPC: What's the Difference?

As a seller, you've likely come across the terms SKU and UPC. However, many don't know what they actually mean. Are they the same as barcodes? How do they impact businesses?

This guide explains the differences between SKU vs UPC, their meanings, and how to use both effectively to simplify your inventory, sales, and logistics.

Key Takeaways

  • SKUs are internal codes used to track inventory within your business.

  • UPCs are standardized product identifiers used globally for retail and scanning systems.

  • Both codes help with inventory accuracy, product identification, and selling across platforms.

  • Canadian sellers must get UPCs from GS1 Canada, while SKUs can be created in-house.

What is an SKU (Stock Keeping Unit)

A box with a code scanned by a green scanner

An SKU, or Stock Keeping Unit, is a unique alphanumeric code assigned to each product in your inventory. Sellers use SKUs to track products internally, making it easier to organize, reorder, and analyze inventory. You can customize SKUs based on product features like colour, size, or brand.

For example:

You are selling a red, medium-sized t-shirt. You can have an SKU like: TSH-RED-M.

What is a UPC (Universal Product Code)

A box with a code magnified by a magnifying glass

A UPC, or Universal Product Code, is a 12-digit numeric barcode that identifies a product globally. Retailers and online marketplaces use UPCs to scan and track items during checkout. Sellers must get UPC codes through GS1 Canada, the official issuing body in the country.

Unlike SKUs, UPCs are standardized and recognized by systems worldwide, making them essential if you plan to sell on Amazon, Walmart, or in retail stores.

For example:

The iPhone Lightning Cable has a product description "Electronics accessory sold in retail" and a UPC of 190198496911.

Here's the breakdown:

190198 – Manufacturer code (Apple’s GS1 prefix)

49691 – Item reference number (specific to the Lightning Cable product)

1 – Check digit (automatically calculated for barcode accuracy)

Important Notes for Canadian Sellers:

  • UPCs for products you manufacture or private-label must be obtained from GS1 Canada to avoid duplication.

  • You cannot make up your own UPC barcode if you're selling on major marketplaces like Amazon or Walmart.

  • Each product variation (e.g., size, colour, or flavour) must have its own unique UPC.

SKU vs UPC vs Barcodes: Are They Similar?

SKUs and UPCs are both related to barcodes, but only the latter are barcodes by default. A UPC number is a barcode that can be scanned by retail systems.

SKUs, on the other hand, are just text or alphanumeric identifiers created for internal use. That said, you can still generate a barcode image if you want to use SKU labels for scanning in the warehouse or POS systems.

What are the key differences between SKU and UPC?

An infographic about the differences of sku and upc

While both are used to identify products, they serve different purposes and are created differently. Let’s break down the key differences between these two product identifiers.

Definition

An SKU is an internal code created by a business to track and manage inventory. A UPC, however, is an external code issued by GS1 to identify products in retail systems.

Primary Function

SKUs help with inventory management, stock tracking, and reporting. Meanwhile, UPCs enable product identification and scanning in stores, online marketplaces, and throughout the supply chain.

Issuing Authority

SKUs are created in-house by the seller for internal inventory tracking. On the other hand, UPCs are assigned by GS1 Canada and follow global standards.

Uniqueness Scope

An SKU is unique within your business only. As for the UPC, it is a unique global trade item number standardized across industries.

Format and Structure

SKUs are tailored using an alphanumeric, flexible format (e.g., 'SHOE-WHT-7M'). In contrast, UPCs follow a 12-digit numeric barcode format (e.g., "123456789012").

Flexibility

SKUs are highly customizable to suit internal needs within an inventory management system. In comparison, UPCs are not customizable and follow a fixed GS1-defined structure for external use.

Customer Visibility

SKUs are usually not seen by customers unless printed on packing slips or receipts. The 12 digits of the UPC GTIN are visible on product packaging and used during checkout.

Usage Context

SKUs are ideal for internal tracking, inventory audits, and sales analytics as opposed to UPCs. The latter is used as a unique identifier by retailers and suppliers. It is also required for selling through retail channels, marketplaces, and global supply chains.

How to Manage SKUs and UPCs

Boxes arranged in a rack with a yellow clipboard on the sid

Managing UPC vs SKU codes properly can save you time, reduce errors, and help your eCommerce business grow. Here are practical tips for handling each:

SKUs

1. Develop a Consistent Naming Convention

Use a clear and logical SKU system. Include product details, such as the product type, colour, and size. For example: TSH-BLK-L

  • Product Type: T-Shirt (TSH)
  • Colour: Black (BLK)
  • Size: Large (L)

2. Use Inventory Management Software

Use tools like QuickBooks, Shopify, or Zoho Inventory. They can automate SKU tracking to reduce manual work and mistakes, and make inventory management more efficient.

3. Organize Variants with Parent SKUs

Group similar products under a parent SKU to keep your catalogue clean. You can assign each variant a unique SKU to make tracking more efficient.

For example:

SHOE-BLK could be the parent, and SHOE-BLK-8 and SHOE-BLK-9 represent size variants with their own unique SKUs.

4. Track and Analyze SKU Performance

Use your SKUs to analyze product performance by identifying which items sell best and which need restocking or discounting.

5. Train Your Team

Ensure your staff understands your SKU system properly. They should know how to use a barcode scanner to handle inventory, orders, and customer questions accurately.

UPCs

1. Get UPCs from GS1 Canada

To ensure your UPCs are globally recognized, register with GS1 Canada. They will assign you a company prefix and help you create a valid identification number for each UPC.

2. Assign UPCs Correctly

Each specific product, including every size or colour variant, needs its own unique UPC. Avoid reusing the same UPC for different items.

3. Print and Apply Barcodes

After receiving UPCs, print the barcodes and add them to your product package. The codes are used during checkout and inventory tracking. Use a reliable label printer to ensure scannability.

4. Integrate UPCs in Your Sales Channels

Input UPCs into your product listings on Amazon, Walmart, or other marketplaces. This allows accurate product identification and makes your products searchable and scannable at checkout.

5. Audit UPC Usage

Regularly review your UPC assignments to avoid duplicates or mislabeling. Keeping your database accurate ensures smooth operations across platforms and provides valuable insights into product performance.

Final Thoughts

Understanding the difference between UPCs and SKUs is crucial for Canadian online sellers. To repeat, SKUs help with internal organization, while UPCs are essential for external selling and meeting global standards. By using both codes correctly, you can reduce inventory issues and run your eCommerce business more efficiently.

Let Stallion Help You Understand SKU vs UPC Better

At Stallion, we’re more than just a shipping company—we’re a trusted 3PL partner for Canadian eCommerce sellers. Our job is to make shipping and order fulfillment easier for you.

Whether you’re adding new products, organizing your inventory, or selling on more marketplaces, we’re here to help. We take care of the behind-the-scenes work like storing your items, packing orders, and shipping them to your customers.

By letting us handle the logistics, you’ll have more time to focus on growing your business. You can easily ship to your customers regardless of where they are— sending across the country, to the US, or even internationally.

With Stallion as your partner, you can save money on shipping, deliver faster, and keep your customers happy.

Get started today! Ship faster, smarter, cheaper with Stallion.

Get Started Today.  Sign Up for Free!

More from the blog

A box with a white circle sticker of a globe and a shopping cart

Stickering 101: What It Is and Why It Matters in E-Commerce

You've probably heard the term stickering tossed around, especially if you work with warehouses, 3PLs, or platforms like Amazon. It sounds like it's just about slapping labels on boxes, but it is a big deal in eCommerce. This guide breaks down what stickering means, how it works, and why it's a significant part of running […]
A forklift carrying packages vs a ship carrying shipping containers

Difference Between Cargo Vs Shipment: A Simple Guide for Sellers

Many eCommerce businesses in Canada interchange cargo vs shipment more times than you can count. But are they actually the same thing? This simple guide breaks down the differences between cargo and shipment. Not only that, but we will also discuss the types of each and how Canadian sellers like you can simplify your shipping […]
A thinking 3D-graphic man holding a pen and a notebook

A Beginner’s Guide to Supply Chain Integration

Running an online store in Canada is exciting, but let's be real—it also comes with its fair share of challenges. Between keeping products in stock, managing suppliers, and making sure customers get their orders on time, things can get overwhelming. Here's where supply chain integration comes in. In this guide, we'll break it down in […]

Join our community

Follow @ShipStallion
Can our fellow Torontonians relate? -#smallbusiness #business #entrepreneur #socialmedia #shipping #ecommerce #canadianecommerce #shopify #poshmark #b2b #saas #etsy #ebay #canada #canadiansmallbusiness #shoplocalcanada #entrepreneur #toronto
Here’s your quick hassle free shipping from 🇨🇦 to 🇺🇸 as a business owner! -Any questions?! Leave them 👇🏻 and save this video so you don’t forget! -#smallbusiness #business #entrepreneur #socialmedia #shipping #ecommerce #canadianecommerce #shopify #poshmark #b2b #saas #etsy #ebay #canada #canadiansmallbusiness #shoplocalcanada #entrepreneur
Meet @drinkbenny a 🇨🇦 female founded energy drink brand! Instead of focusing on their products, they’re taking a unique approach by hosting in person events in different Canadian cities to offer an experience for their community 🧡- What are your thoughts on in person events? 💭 -#smallbusiness #business #entrepreneur #socialmedia #shipping #ecommerce #canadianecommerce #shopify #poshmark #b2b #saas #etsy #ebay #canada #canadiansmallbusiness #shoplocalcanada #entrepreneur
Do you know the difference between DDU and DDP when shipping internationally 🌏 ?-Questions? Leave them below! 👇🏻 -#smallbusiness #business #entrepreneur #socialmedia #shipping #ecommerce #canadianecommerce #shopify #poshmark #b2b #saas #etsy #ebay #canada #canadiansmallbusiness #shoplocalcanada #entrepreneur
Here’s a quick hack to save time from choosing multiple postage options ↪️ Turn on the lowest postage rate automation to save you time! -Questions? Leave them below! 👇🏻 -  #smallbusiness #business #entrepreneur #socialmedia #shipping #ecommerce #canadianecommerce #shopify #poshmark #b2b #saas #etsy #ebay #canada #canadiansmallbusiness #shoplocalcanada #entrepreneur
This error message is only visible to WordPress admins
There has been a problem with your Instagram Feed.

Join Stallion to save up to 75% on shipping today!

linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram