Amazon
+
eBay
Marketplaces + Marketplaces

Amazon eBay Integration

Nventory syncs inventory levels between Amazon and eBay in real time and pulls orders from both marketplaces into a single dashboard. When a unit sells on one channel, Nventory updates the other within seconds to prevent overselling.

Sellers on both Amazon and eBay see up to 40% more revenue with synchronized inventory preventing an average of 12 canceled orders per month
amazon ebay inventory syncsell on amazon and ebayamazon ebay order managementsync amazon ebay stock
Amazon
NV
eBay

Sync Matrix

6 data entities in the sync matrix — 2 bidirectional, 4 one-way. Tap any row for details.

Good to Know

Platform restrictions outside any integration tool's control

Customer identity and contact data

Both Amazon and eBay own the customer relationship. Buyer emails are anonymized and cannot be exported or shared between marketplaces.

Amazon Buy Box status

Amazon does not expose real-time Buy Box ownership via API. Nventory keeps inventory accurate but cannot guarantee or influence Buy Box wins.

eBay Promoted Listings and Amazon PPC campaigns

Advertising on both platforms is managed through separate ad systems (eBay Promoted Listings, Amazon Advertising Console) outside Nventory's sync scope.

eBay auction bid history

Individual bid amounts and bidder identities are not accessible via API. Only winning bids sync as completed orders.

Things to Consider

Platform-specific details and how they affect this integration.

Challenge

Amazon and eBay compete for the same shared inventory pool. During Prime Day, Amazon demand spikes dramatically, while eBay may see slower traffic. Conversely, eBay auction events and holiday shopping can pull stock away from Amazon. Without careful allocation, one marketplace cannibalizes the other.

Nventory's Approach

Nventory lets you set percentage-based splits, fixed reserves, or velocity-based dynamic allocation per SKU. Pre-configure seasonal rules that automatically shift inventory toward Amazon during Prime Day or toward eBay during holiday auction season.

Who Uses Amazon eBay Integration

Common scenarios for connecting Amazon and eBay.

A consumer electronics reseller listing refurbished products on both Amazon and eBay who needs instant stock deductions across channels
An Amazon FBA seller expanding to eBay to diversify revenue and reduce dependency on a single marketplace
A multi-warehouse operation shipping FBM orders from regional warehouses while also using FBA for Prime-eligible listings
A vintage and collectibles dealer who runs eBay auctions but also maintains fixed-price Amazon listings for steady sales

How It Works

Nventory sits between your platforms and keeps everything in sync.

Amazon
Amazon
NV
Nventory
eBay
eBay
1

Connect Both Accounts

Link your Amazon Seller Central and eBay Seller Hub accounts to Nventory with secure OAuth. FBA and FBM channels are detected automatically.

2

Map SKUs and Listings

Nventory matches your Amazon ASINs to eBay item IDs by SKU, UPC, or manual mapping. Variants, bundles, and kits are fully supported.

3

Set Allocation Rules

Define how much stock each marketplace can sell. Set fixed reserves, percentage splits, or let Nventory dynamically allocate based on velocity.

4

Go Live with Real-Time Sync

Inventory, orders, and tracking numbers flow through Nventory between Amazon and eBay continuously. Monitor sync health from the dashboard.

Frequently Asked Questions

Yes. Nventory reads your FBA fulfillable inventory in real time and includes those counts when calculating available stock for eBay listings, so your eBay quantities always reflect actual FBA availability.

Nventory detects the completed auction within seconds and reduces the corresponding Amazon listing quantity. If the item was the last unit, the Amazon listing is set to zero to prevent an oversell.

Absolutely. Nventory syncs inventory quantities, not pricing. You maintain independent pricing strategies on each marketplace, including eBay promotional pricing and Amazon Buy Box competitive pricing.

Inventory updates propagate within seconds of an order event. Nventory uses webhooks and high-frequency API polling to ensure near-instant synchronization between both marketplaces.

Yes. Return statuses from both marketplaces appear in a unified view. When a returned item is restocked, Nventory adjusts available inventory on both channels automatically. Refund processing itself is handled within each marketplace's native system.

Nventory maintains configurable safety stock buffers per marketplace so the true last unit is never exposed on both channels at once. If a race condition occurs, Nventory's conflict resolution flags the duplicate sale within seconds, letting you cancel the later order before it ships and protecting your Amazon account health and eBay Top Rated Seller defect rate.

Start by checking FBA reserved stock, which includes units set aside for customer orders, transfers, and processing — these quantities often do not sync to eBay, causing apparent mismatches. Next, verify that eBay listing variations (size, color) are correctly mapped to the corresponding Amazon child ASINs. Run a manual reconciliation in Nventory's dashboard to identify and resolve any remaining quantity gaps across both channels.