To sell on OnBuy, you register as a seller, list your products in the format OnBuy requires, and keep your stock and orders in sync. The quickest way to do all three is to connect your existing store to OnBuy with Koongo, which automates the data work so you can list in an afternoon rather than a month.

But before the how, the why. OnBuy has a few things going for it that set it apart from the marketplaces most sellers start with. Here’s what OnBuy is, why sellers are moving to it, the one real challenge in getting listed, and exactly how Koongo handles that challenge.

This offer is an early-bird deal: pay for one month of your seller subscription by 31 July 2026, and your next 12 months of subscription are free, so you get 13 months of selling for the price of one. Because OnBuy, easyShop, and Comet all run on the same OnCommerce account, that single subscription covers all three marketplaces as they launch. Standard selling fees on your actual sales still apply, so it’s the subscription cost that’s waived, not selling on the platform entirely.

A new marketplace, easyShop, is launching for peak season 2026, and if you already sell on OnBuy you’re closer to being on it than you might think. The reason is OnCommerce: the platform that connects OnBuy, easyShop, and the returning Comet brand, letting sellers reach all three through a single account and a single product catalogue.

But what exactly is OnCommerce, how does the one-account model work, and what does each marketplace offer a seller? This guide breaks it down in plain terms: what OnCommerce is, the three marketplaces it powers, how listings, stock, and payments stay in sync across them, and the early-bird offer that gives you 12 months of subscription free if you join by 31 July 2026. We also cover how to connect your store to all three with Koongo, with no coding required.