How to Sell on OnBuy: UK Seller Guide (2026)

What is OnBuy?

OnBuy is a British marketplace founded in Bournemouth in 2016, built explicitly as a seller-friendly alternative to Amazon. Its structural difference: OnBuy is a pure marketplace — it holds no stock and retails nothing itself. Your sales data can never be used to launch a competing house-brand product, the accusation that has dogged Amazon for years.

For buyers it looks familiar — product pages with multiple seller offers, cashback incentives, mainstream categories. For sellers, it's the most accessible of the UK marketplaces: open registration rather than curated invitation, unlike Tesco or B&Q.

Fees

• No listing fees — list your entire catalogue at zero cost
• Category-based commission per sale — historically among the lower UK marketplace rates (single digits in many categories; confirm your category's current rate at registration)
• Monthly subscription for business sellers — modest, tiered by plan

The zero-listing-fee structure changes the expansion maths: putting 2,000 SKUs on OnBuy costs nothing until they sell. There is no reason not to list your full catalogue — the only real cost is operational (keeping one more channel's stock accurate), which is a software problem, not a fee problem.

Registration

1. Register as a business seller on OnBuy's seller portal — business details, VAT where applicable, bank details for payouts
2. Verification checks (identity, business legitimacy)
3. Choose a subscription tier
4. Start listing — no category gatekeeping in most areas

Approval is dramatically faster than the curated retail marketplaces — days, not weeks. That makes OnBuy an ideal second or third channel to validate multi-channel operations before applying to the harder ones.

Listing: the barcode-driven model

OnBuy identifies products by GTIN/EAN barcode, Amazon-style. Multiple sellers attach offers to one shared product page:

• Product exists? List against it by EAN in seconds — price, quantity, condition, delivery.
• New product? Create it with your barcode, title, images and attributes. You control the page quality; better data converts better for everyone who later shares it.

Winning the shared page (OnBuy's equivalent of the buy box) comes down to price, delivery speed and seller performance. If your catalogue lacks proper EANs, resolve that first — our SKU and barcode guide covers the difference between internal SKUs and GTINs and when you need each.

Fulfilment and payments

• You fulfil every order — OnBuy has no fulfilment service, so your existing dispatch operation carries straight over
• Stated handling times and tracked delivery expected; seller metrics monitored
• Payments processed via OnBuy's payment provider on a regular payout cycle

Running OnBuy alongside everything else

Nobody sells onlyon OnBuy — it's an additive channel on top of eBay, Amazon or Shopify. Which makes the operational question the usual one: the same stock is now promised in one more place. A sale on eBay must update your OnBuy offers within seconds, or OnBuy's buyer purchases stock you already sold — cancellation, defect, ranking damage.

With Salync, OnBuy is one more connected channel on the same stock ledger as eBay, Amazon, Shopify and the Mirakl marketplaces: list from one catalogue by EAN, sync stock in real time, and pull OnBuy orders into the same dispatch queue. Zero listing fees on their side, free up to 50 SKUs on ours — the cheapest multi-channel experiment available to a UK seller.

OnBuy vs eBay vs Amazon — quick positioning