Can you sell the same product on Amazon and eBay?

Yes — selling the same product on both Amazon and eBay is a common strategy. The key is using inventory management software to keep stock levels in sync, so a sale on one platform immediately reduces availability on the other.

How do I sync stock between Amazon and eBay?

You need inventory management software that connects to both platforms. When a sale happens on either channel, the software deducts from your central stock count and pushes the updated quantity to both Amazon and eBay in real time.

Is it better to sell on Amazon or eBay?

Both platforms have different strengths. Amazon has a larger buyer base and suits new, branded products. eBay is better for used goods, unique items, and sellers who want more control over their listings. Most successful UK sellers use both.

How to Sell on Amazon and eBay at the Same Time (Without Overselling)

Selling on both Amazon and eBay doubles your reach — but it also doubles your chances of overselling. Here's how to run both channels efficiently without the inventory headaches.

Why sell on both Amazon and eBay?

Amazon and eBay attract different types of buyers. Amazon customers tend to search for specific products by brand or model — they know what they want and expect fast Prime delivery. eBay buyers are more likely to browse, compare prices, and buy used or unique items.

For most UK sellers, being on both platforms means reaching buyers you'd miss on either one alone. The same product can sell faster on Amazon for buyers who want it new, and on eBay for buyers hunting a deal.

The main challenge: keeping stock in sync

Imagine you have 5 units of a product. You list all 5 on Amazon and all 5 on eBay. Three sell on Amazon. Now Amazon shows 2 — but eBay still shows 5. A customer buys 3 on eBay. You've now sold 6 units you only had 5 of.

This is the overselling problem, and it's the number one reason sellers get negative feedback, account warnings, and order cancellations.

Amazon vs eBay: key differences for sellers

	Amazon	eBay
Fees	~15% referral fee	~12.8% final value fee
Listing control	Limited — shared listings	Full control
Best for	New, branded products	Used, unique, or niche items
Buyer trust	Very high	High
Fulfilment	FBA or FBM	Self-fulfilled
Returns	Amazon manages	Seller manages

How to sync Amazon and eBay stock automatically

The reliable solution is inventory management software that acts as a central hub:

Connect both your Amazon and eBay seller accounts
Import your products into a single catalogue
The software monitors sales on both platforms
When a sale happens anywhere, it deducts from central stock and updates both channels

With Salync, this sync happens automatically every cycle — so your eBay and Amazon listings always reflect your true available stock. You set it up once and it runs in the background.

Setting your prices across both channels

Amazon charges around 15% in referral fees. eBay charges around 12.8%. If you sell at the same price on both, you're making different margins. Many sellers price slightly higher on Amazon to account for the difference.

A simple rule: calculate your target net price, then add the platform fee percentage on top. For a product where you want £20 net:

Amazon price: £20 ÷ 0.85 = £23.53
eBay price: £20 ÷ 0.872 = £22.94

Amazon FBA vs eBay self-fulfilment

Many Amazon sellers use FBA (Fulfilment by Amazon)— Amazon stores and ships the products for them. If you use FBA for Amazon and self-fulfil on eBay, you're essentially running two separate stock pools.

This is fine, but means your inventory system needs to track FBA stock separately from your own warehouse stock. Make sure your software handles this distinction — Salync tracks stock per location, so FBA and self-held stock are kept separate.

Tips for managing both channels efficiently

Use the same SKUs on both platforms

Consistent SKUs make it much easier to match listings across platforms and spot discrepancies. If your Amazon ASIN maps to a different SKU than your eBay listing, syncing becomes complicated.

Monitor your seller metrics on both

Amazon tracks your order defect rate, late shipment rate, and cancellation rate. eBay tracks your feedback score and service metrics. Overselling hurts both. Keep an eye on both dashboards especially during busy periods.

Set conservative reorder points

When selling on multiple channels, you can sell through stock faster than expected. Set your reorder points based on combined daily sales across all channels, not just one.