How a crypto payment works
What happens at checkout
Five steps, and four of them happen without you doing anything.
You choose crypto as the payment method and pick a coin and network. The seller’s payment gateway generates a fresh address for this order and shows it, usually with a QR code and a countdown. You send the exact amount from your wallet. The gateway watches the network, sees the transfer, waits for the required confirmations and marks the order paid.
The countdown matters. The quoted amount is locked to a rate for a limited window, commonly ten to twenty minutes, because the coin’s price moves. Pay after it expires and the amount may no longer match.
What it costs the payer
Usually just the network fee, and that depends entirely on the chain rather than on the seller.
Fractions of a cent on Solana or TON. Around a dollar on TRON. Several dollars on Ethereum when the network is busy. For a twenty-dollar purchase, choosing the network thoughtfully is the difference between a fee you ignore and one you notice.
Some sellers pass their processing fee to the customer. Most absorb it, because crypto processing costs them less than cards do.
Which coin to pay with
Two considerations, and they usually point the same way.
Stablecoins avoid the awkwardness of spending an asset whose price might jump the following week. Paying in USDT or USDC costs you a dollar for a dollar of goods.
Volatile coins work fine mechanically. The consideration is personal rather than technical: spending Bitcoin means realising whatever position you were holding, and in many jurisdictions that is a taxable event.
When something goes wrong
Four situations, in order of how often they occur.
Underpaid
The amount fell short, often because the wallet deducted the fee from it. The order stays unpaid, and the seller usually asks for the difference or refunds the partial amount.
Overpaid
Sellers generally credit or refund the excess, and it needs raising rather than assuming.
Wrong network
The most expensive mistake. Sending on a chain the seller does not watch means the funds went somewhere nobody is looking. Recovery depends on who controls the destination.
Late
The transfer confirmed after the window closed. Provide the transaction hash and the seller can match it manually.
How the hash settles all four
In all four cases the hash settles the question in seconds, which is why sellers ask for it first.
Refunds
A crypto payment cannot be reversed by a bank, because no bank is involved. There is no chargeback mechanism at all.
A refund is therefore a new transfer in the opposite direction, sent by the seller to an address you provide. This puts the decision entirely with the seller, which is worth knowing before paying somebody you have no reason to trust.