Definition
A seller account a platform creates and manages inside its payment provider to receive funds and be paid out.
A connected account is how a platform holds and moves money on a seller's behalf without that seller opening their own merchant account. It is the unit a platform onboards, verifies, gates by capability, and pays out — and the unit that can go into a negative balance when a refund or chargeback lands after payout.
The term is closest to a sub-merchant, but the framing differs: a sub-merchant describes the card-network relationship under a payment facilitator, while a connected account describes the provider-side account object a platform operates. For how connected accounts are run in practice — onboarding, payout holds, reserves, split payments, and dispute liability — see the marketplace split-payment operations runbook.
Capabilities are separate switches, and that matters operationally. Accepting charges, receiving transfers, and being paid out are gated independently. A connected account can be live enough to take money while still blocked from receiving a payout — usually because verification is incomplete or a risk review is open. Platforms are frequently surprised by this: the seller is transacting, the buyer is charged, and the funds simply accumulate. Treat payout capability as a distinct state to monitor, not as something implied by a successful charge.
The negative balance is the failure mode to design for. Refunds and chargebacks land against the connected account, and they routinely land after the seller has been paid out. If the account has no balance to debit, the shortfall does not disappear — it becomes the platform's problem, because the platform, not the seller, is the provider's counterparty. This is why reserves, payout delays, and a documented recovery path exist. A platform that pays out instantly and holds no reserve has chosen to self-insure seller refund risk, whether or not it framed the decision that way.
Connected account is not a synonym for sub-merchant. A sub-merchant is a card-network status under a payment facilitator's master merchant account. A connected account is a provider-side object. The same seller can be both, one, or neither depending on the model — and the labels answer different questions. Sub-merchant tells you who the networks hold accountable; connected account tells you what the platform can operationally do to that seller's money.