Crosslist from eBay to OnBuy
Move your barcoded stock from eBay to OnBuy. eBay sales end OnBuy listings automatically. OnBuy sales require manual marking in FLUF.
7 days for £1, then from £9/month.
- Good fit for OnBuy: Retail products with barcodes (GTIN, EAN, UPC, ISBN). New or lightly used items with valid product identifiers.
- Poor fit for OnBuy: One-off vintage or used items without a barcode. FLUF supports OnBuy’s UK marketplace. Barcodes are mandatory.
- eBay: 35 million UK and international buyers. 12.8% final value fee plus 40p per order (over £10).
- OnBuy: UK marketplace for retail stock. Subscription model plus category-based commission. No listing fees.
- Sync behaviour: When an item sells on eBay, FLUF ends the OnBuy listing automatically. When it sells on OnBuy, mark it sold in FLUF to remove the eBay listing.
- Your workflow: Select eBay items, verify they have a barcode, crosslist to OnBuy. FLUF copies the listing details; you review before publishing.
Is OnBuy the right channel for your eBay stock?
OnBuy is not for every eBay seller. OnBuy requires a valid barcode (GTIN, EAN, UPC or ISBN) on every listing. If you sell mostly one-off vintage clothes, used books without an ISBN, or handmade items, OnBuy cannot accept them. If you hold new retail stock with barcodes—electronics, sports equipment, books, beauty products—OnBuy is worth a second channel.
eBay thrives on breadth. Auctions, rare finds, second-hand goods. Buyers hunt bargains and niche items. OnBuy is a retailer’s marketplace: product-led, barcode-driven, subscription-backed. OnBuy buyers expect new or very lightly used goods with intact packaging. The buyer demographics are different, but there is overlap. New-in-box surplus, overstock and branded goods sell well on both platforms.
OnBuy’s strength is high-volume retail. If you have 50 identical printer cartridges with the same barcode, OnBuy rewards scale. Your listing is joined with other sellers of the same product; the marketplace shows stock from all sellers together. If you have one-of-a-kind pieces, eBay is your primary platform. Specialist vintage communities exist there, and buyers accept single listings for unique items.
How Inventory Syncs Between eBay and OnBuy
eBay has built-in sale detection. When FLUF sees a sale on eBay, it ends the listing on OnBuy. This prevents you from overselling: the same item will not be sold twice.
OnBuy sales are not automatically detected by FLUF. The system has no way to know when an item sold on OnBuy. So when an item sells on OnBuy, you must manually mark it sold in FLUF. Once marked, FLUF will remove the eBay listing.
This asymmetry matters for your workflow. An eBay sale is safe from overselling: FLUF handles the removal automatically. An OnBuy sale requires a manual step from you. If you forget to mark it sold in FLUF, you risk overselling the item on eBay. Check your OnBuy seller account regularly for new sales.
| Event | What Happens | Manual Action Needed? |
|---|---|---|
| Item sells on eBay | FLUF ends the OnBuy listing automatically | No |
| Item sells on OnBuy | No automatic detection | Yes. Mark the item sold in FLUF to remove the eBay listing |
Why OnBuy Requires a Barcode and eBay Doesn’t
eBay lets you create a listing with just a title, images and description. You define the product yourself.
OnBuy requires a GTIN (barcode): an EAN-13, UPC-12, ISBN or equivalent. This barcode links your offer to OnBuy’s product record. OnBuy does not create a new product page for you. Instead, it attaches your stock to an existing product that OnBuy has already catalogued in its database.
This is similar to Amazon‘s model. On Amazon, you add an offer to an existing product page rather than writing a standalone listing. The product page is shared across all sellers. Buyers see one product title, one set of product images, and multiple sellers offering the same item at different prices. On OnBuy, the model is the same. Your barcode is the key. It tells OnBuy which product you are selling.
If OnBuy cannot find the barcode in its catalogue, you cannot list the item. There is no option to create a new product page yourself or request one. The barcode must exist in OnBuy’s records before you can add your offer.
The barcode is how OnBuy prevents duplicate listings and keeps its marketplace clean. One product, many sellers. Vintage sellers face a challenge: a one-of-a-kind piece often has no barcode. A book without an ISBN. A garment with no tag barcode, only a custom label. These items cannot be listed on OnBuy. Handmade goods, custom orders, personal creations, second-hand one-offs: OnBuy does not support them.
New retail goods almost always have a valid barcode. Books have ISBNs. Electronics come with EAN-13 labels. Beauty products, DIY, sports equipment: all carry barcodes. Overstock and surplus from retailers come with barcodes intact. That is OnBuy’s sweet spot. If your eBay inventory is mostly new branded stock, OnBuy crosslisting is straightforward. If it is mostly vintage and one-off items, OnBuy will not accept most of them.
How to Crosslist from eBay to OnBuy with FLUF Connect
- Have a FLUF Connect account and an OnBuy seller account. Connect OnBuy using your seller credentials (no third-party app needed).
- In FLUF Connect, open your eBay inventory. Select the items you want to list on OnBuy. Filter by category or brand if you have many.
- Check that each item has a valid barcode. Items without a barcode cannot be crosslisted to OnBuy. Your eBay listing should show the barcode in the product details.
- Click Crosslist to OnBuy. FLUF copies the listing and you review it before it goes live.
- Review and publish. Check that the title, price and description look right. Then publish the listings to OnBuy.
Selling Fees: eBay vs OnBuy
eBay and OnBuy have different fee models. Understanding both helps you price competitively and choose which platform to prioritise.
| Fee Type | eBay (UK Business) | OnBuy |
|---|---|---|
| Monthly subscription | None (optional shop subscription) | £25–£249/month depending on tier |
| Final value fee / commission | 12.8% of sale plus postage | 5–20% commission by category |
| Per-order fee | 40p for orders over £10 | Included in subscription |
| Insertion / listing fee | 35p per item after 1,000 free monthly | None |
Worked Example: Selling a £50 Item
You sell an electronics item for £50 (including £3 postage) on both eBay and OnBuy.
On eBay (Business):
- Final value fee: 12.8% × £50 = £6.40
- Per-order fee (over £10): £0.40
- Total fees: £6.80 (13.6% of sale)
- You keep: £43.20
On OnBuy (Standard Plan, 7% commission for Electronics):
- Monthly subscription (spread over 30 sales): approximately £0.83 per sale
- Commission: 7% × £50 = £3.50
- Total fees: £4.33 (8.7% of sale)
- You keep: £45.67
OnBuy‘s model favours high-volume sellers. If you sell only 5 items a month, the £25 subscription is expensive per sale. If you sell 100 items a month, it becomes very cheap per unit. eBay charges per transaction, so high volume on eBay also builds fees quickly. For sellers moving 10+ items per month, OnBuy’s subscription cost works out to roughly half the percentage fee of eBay on most categories.
What FLUF Connect Costs
You can try it with 7 days for £1, then from £9/month.
| Plan | Monthly | Crosslisted products |
|---|---|---|
| Starter | £9/month | Unlimited |
| Seller | £29/month | Unlimited |
| Pro | £99/month | Unlimited |
| Super Seller | Custom pricing — tell us what you need | Unlimited |
Save 40% when you pay yearly.
Every plan includes crosslisting to 54 marketplaces and bulk operations. Relisting and offer management are available on eBay, Vinted, Depop and Etsy. OnBuy supports crosslisting and sold-elsewhere removal only in FLUF.
Sources
- eBay UK business seller fees (eBay official page)
- OnBuy seller subscription plans and costs (Nembol, 2026)
- GS1 barcode standards and formats
Sources checked September 2026.
Related guides
Frequently Asked Questions
No. OnBuy requires a valid GTIN (barcode: EAN-13, UPC-12, ISBN or equivalent) on every listing. Items without a barcode cannot be listed on OnBuy. Vintage, one-of-a-kind, or handmade items typically do not have barcodes, so they are a poor fit for OnBuy.
Yes. When a sale is detected on eBay, FLUF automatically ends the OnBuy listing. You do not need to manually delist it. However, the reverse is not automatic: if an item sells on OnBuy, you must mark it sold in FLUF to end the eBay listing.
OnBuy charges a monthly subscription (from £25 for the Standard plan) and a category-based commission ranging from 5% to 20% of each sale (most categories 7–15%). There are no per-listing fees. Your actual fees depend on your sales volume and the categories you sell in. eBay charges per transaction (12.8% final value fee plus a fixed per-order fee), so OnBuy may be cheaper at high volume.
FLUF supports OnBuy’s UK marketplace. Everything on this page is written for a seller listing on onbuy.com in the UK.
FLUF Connect supports crosslisting and automatic removal of OnBuy listings when items sell elsewhere. Relisting and offer management are not available for OnBuy in FLUF. These features work on other channels like eBay, Vinted, Depop and Etsy.
OnBuy attaches every listing to a product record by barcode (GTIN, EAN, UPC or ISBN). An eBay item with no barcode is not a fit for OnBuy, so keep it on eBay and your other channels.
You see it in your OnBuy seller account. FLUF does not see OnBuy sales, so when one comes in, mark the item sold in FLUF and the eBay listing ends.
Yes. FLUF Connect allows bulk crosslisting. Select multiple items, check they all have valid barcodes, and crosslist them all at once. Review the copied listings before you publish them to OnBuy.