# Who pays the gas in an x402 payment? The facilitator pays the gas. An x402 buyer signs an authorisation rather than sending a transaction, so it needs no native token at all. The facilitator wraps the signature in a transaction, pays for the block space and recovers that cost through its own pricing. On a cheap chain the gas is a fraction of a cent. Published: 2026-10-14 Last reviewed: 2026-10-14 Publisher: Roundhouse AI Ltd. Source: https://roundhouseai.io/resources/who-pays-gas-in-x402 --- ## Why does this question matter? Because the answer determines whether an autonomous buyer is operationally viable. A wallet that must hold two assets needs both of them topped up. The second one, the native gas token, is the one that runs out quietly: it is not what the agent is spending, nobody is watching it, and when it hits zero every payment fails for a reason that has nothing to do with the payment. Multiply that across a fleet of wallets and it is a permanent maintenance burden. x402 removes the second asset entirely. The buyer holds a stablecoin and nothing else. ## How does that work mechanically? The buyer never sends a transaction. It produces a signature over a transfer authorisation, using [EIP-3009](https://roundhouseai.io/resources/eip-3009-transfer-with-authorization-explained) on EVM chains or the equivalent elsewhere, and hands it to the server in the [X-PAYMENT header](https://roundhouseai.io/resources/x-payment-header-explained). The [facilitator](https://roundhouseai.io/resources/what-is-an-x402-facilitator) submits that signature to the token contract. The transaction is sent from the facilitator's address, so the facilitator's address is what pays the gas. The transfer that results moves funds from the buyer to the seller, untouched by either. | Party | Signs | Broadcasts | Pays gas | Holds native token | | --- | --- | --- | --- | --- | | Buyer | Yes | No | No | No | | Seller | No | No | No | No | | Facilitator | No | Yes | Yes | Yes | Note that the seller does not need a native token either. This is the part sellers tend to discover with relief: taking on-chain payments does not require operating on-chain. ## Who ultimately bears the cost? The facilitator pays it and recovers it, and how it recovers it varies. - **Per-transaction fee.** The most common model. Coinbase's facilitator has published a free tier followed by a small per-transaction charge, with figures around a tenth of a cent reported in 2026. Check current pricing directly rather than trusting a figure from an article. - **Spread on the payment.** Some facilitators take a cut of the settled amount instead of a flat fee. - **Free, as a loss leader.** Several facilitators run without charging, treating it as distribution for something else. This is sustainable while volumes are small and gas is cheap. - **Self-hosted.** A seller running its own facilitator pays gas directly and charges itself nothing, which is the cheapest option at volume and the most work. In every case it ends up in the price. A seller's quoted price has to cover its cost of taking the payment, so gas is a line item in the economics of a sub-cent business whether or not anyone writes it down. > [!IMPORTANT] > Gas cost is why chain choice is an economic decision rather than a preference. At sub-cent prices, a chain where a transfer costs several cents cannot host the business at all: the cost of taking the payment exceeds the payment. This is most of the reason x402 settled on cheap chains rather than Ethereum mainnet. ## What happens when gas spikes? The facilitator absorbs it or stops. On a congested chain, a facilitator charging a fixed fee per transaction is underwater on every settlement until it reprices. The usual responses are to raise the fee, to batch settlements, or to delay them until fees fall. All three are visible to a seller as either a price change or added latency. A seller that cares about this should know what its facilitator does under load, because the failure mode that matters is not a price change but silent delay: a settlement that will happen in twenty minutes, on a request that needed an answer in two seconds. Deferred-payment schemes, including the one Cloudflare published, exist partly for this. Accumulating many small payments and settling them periodically amortises gas across all of them, at the cost of the seller carrying credit risk between settlements. ## Frequently asked questions ### Does the buyer ever need a native token? Not for the payment itself. It may need one for other reasons, such as approving a contract or moving funds between chains, but the x402 path is signature-only. A funded stablecoin balance is the whole requirement. ### Can the facilitator refuse to settle a valid payment? Yes. It controls whether and when the transaction is broadcast. It cannot change the amount or the recipient, since both are in the signed message, but it can decline. This is the main reason a seller should verify and settle rather than treating verification as completion. ### Who pays gas if I run my own facilitator? You do, from a wallet you fund and monitor. Note the irony: by removing the native-token requirement from your buyers you have taken it on yourself, so the wallet that quietly runs out of gas is now yours. ### Is gas included in the price I advertise? It is not a separate field in the x402 terms. Your advertised amount is what the buyer pays and what the seller receives. Any facilitator fee comes out of your side, so it has to be priced in rather than added on. ### Does Solana work the same way? The same principle, a different mechanism. The buyer still authorises rather than broadcasts and a relayer still pays the fee, but the signing scheme is the SPL token program rather than EIP-3009. Solana's fees are low enough that this is rarely the binding constraint. ## Where to check this yourself The settlement record shows who relayed each payment, which is the same thing as showing who paid the gas. [/facilitators](https://roundhouseai.io/facilitators) breaks settlements down by the operator that relayed them, and the [pay an agent without gas](https://roundhouseai.io/docs/guides/pay-an-agent-without-gas) guide walks through the buyer side end to end so you can confirm that a wallet holding only USDC completes a payment. --- Roundhouse indexes x402 settlements and ERC-8004 identities into one public record. - Every article: https://roundhouseai.io/resources.md - Every surface on this site: https://roundhouseai.io/llms.txt - The index, endpoints and schema: https://api.roundhouseai.io/v0 - A key of your own, $0.01 over x402, no account: https://api.roundhouseai.io/v0/test/x402 - Limits and the SQL surface: https://roundhouseai.io/docs/api