Last update: 20 February 2026
Overview
Selling on multiple marketplaces like Amazon, eBay, and Etsy is a smart growth strategy. It allows you to reach different audiences, diversify revenue streams, and reduce reliance on a single platform.
But managing stock across these channels can quickly become challenging. When inventory isn’t aligned, overselling, discrepancies, and manual errors become common. That’s why it’s essential to sync inventory across Amazon, eBay and Etsy to keep your stock accurate in real time.
How to manage e-commerce inventory
Managing e-commerce inventory means having full control over your product quantities, availability, and updates, across all the channels where you sell.
At a basic level, good inventory management includes:
- Using consistent SKUs across all marketplaces
- Keeping quantity stock accurate and updated
- Monitoring stock levels regularly
- Adjusting inventory for returns and cancellations
- Avoiding duplicated listings
If you sell on just one platform, all this can be managed manually. But once you expand to multiple marketplaces, complexity increases quickly.
Each platform has its own system, dashboard, and logic for stock tracking, and none of them automatically communicate with each other.
How to track inventory on Amazon
On Amazon, inventory is managed through Seller Central.
Sellers can:
- View current stock levels from the inventory dashboard
- Monitor available, reserved, and inbound quantities
- Set up restock alerts
- Download inventory reports
- Manage FBA (Fulfilled by Amazon) and FBM (Fulfilled by Merchant) stock separately.
Amazon provides solid internal tools for tracking stock within its own ecosystem. However, those updates stay inside Amazon.
If you sell the same product on eBay or Etsy, Amazon will not adjust those quantities automatically. That means if you receive a sale on eBay or Etsy, you then must manually adjust stock in Amazon.
How do you track your inventory on eBay
On eBay, inventory is tracked directly through your active listings in Seller Hub.
Sellers can:
- Edit quantities individually or in bulk
- Monitor active listings and sales activity
- Access inventory-related reports to review stock levels and listing status.
Inventory on eBay is managed independently, meaning updates made outside the platform won’t be reflected automatically.
How to keep track of Etsy inventory
On Etsy, inventory is managed through the Shop Manager under each listing.
Sellers can:
- Set the available quantity for each product
- Manage variations such as size, color, or material
- Receive low-stock alerts to avoid selling out unexpectedly
- Adjust quantities manually when items are returned or canceled
Etsy updates stock automatically when a sale occurs within its own platform. However, like other marketplaces, Etsy does not synchronize inventory with external channels.
What is multi-channel inventory management
As seen in the previous paragraphs, updating inventory on a single marketplace doesn’t automatically adjust stock levels on other channels. A sale on one platform does not affect the availability of the same item elsewhere, which can lead to overselling, manual errors, and operational inefficiencies.
Multi-channel inventory management solves this problem by providing a centralized system to control and synchronize inventory across all marketplaces. Instead of treating each platform independently, sellers can manage their stock as a single, unified catalog.
This means:
- Maintaining consistent SKUs and product data across channels
- Monitoring inventory levels from one central dashboard
- Automatically updating quantities when a sale occurs
- Reducing the risk of overselling and stock discrepancies
What are the benefits of multi-channel inventory management
Without multi-channel management:
- Risk of selling the same item multiple times
- Time-consuming manual updates
- Risk of cancellations and negative feedback
- Difficulty scaling the business
With a centralized system:
- Inventory stays accurate across all channels
- Updates occur automatically when sales happen
- More efficient and easier to manage operations
- Customer experience improves due to accurate stock information
- Business can scale to additional marketplaces without adding operational complexity
By synchronizing inventory in real time, multi-channel inventory management transforms stock control from a reactive task into a proactive, streamlined process, making multi-channel selling sustainable and scalable.
Best inventory management system
If you sell on Amazon, eBay, and Etsy, the best way to stay on top of your stock is with a third-party inventory management tool — like Nembol.
Nembol provides real-time inventory synchronization across all your channels:
- Sync inventory across Amazon, eBay and Etsy in real time, keeping stock levels accurate
- Eliminate inventory discrepancies, even when managing multiple SKUs or product variations
- Track all updates from a single, intuitive dashboard
- Get stock alerts whenever items are running low, so you can restock on time
Using Nembol ensures that your inventory is always aligned across marketplaces, giving you full control over availability and enabling you to scale your multi-channel business without the risk of stock errors.
How to sync your products with Nembol
Synchronizing your inventory across Amazon, eBay, and Etsy with Nembol is straightforward, but it’s important to understand that only products imported into Nembol from a channel or published through Nembol to a channel will be synced.
Here’s how to set it up:
1. Connect to Nembol your marketplaces
Connect your Amazon, eBay, and Etsy accounts by logging in through Nembol.
2. Import your products
Nembol automatically imports the products from the first connected channel. You can later choose to import products from your other channels whenever you’re ready.
3. Connect existing listings by matching SKU-codes
If your products share the same SKU-code across channels, Nembol will automatically link them for synchronized stock management.
4. Set up stock synchronization
Go to the Channels tab in Nembol and open Sync Settings. Enable Sync stock quantity to Nembol and select which channels you want to update each time a sale occurs on any connected marketplace.
5. Relax and enjoy automated sync
Once activated, Nembol updates your stock automatically across all selected channels. No more manual inventory adjustments, it’s all handled for you.
For a more detailed, step-by-step guide, consult this article.