# Which blockchains support x402? x402 can address any chain by identifier, so spec support is broad. Live settlement is narrower. Through 2026 the chains carrying real x402 volume were Base and Solana, with Stellar, Polygon and Avalanche reachable through facilitators. A chain is usable when a facilitator and a client both support it, not when the spec permits it. Published: 2026-10-14 Last reviewed: 2026-10-14 Publisher: Roundhouse AI Ltd. Source: https://roundhouseai.io/resources/which-blockchains-support-x402 --- ## Three different questions People ask "which chains support x402" and mean one of three things, with very different answers. | Question | Answer | | --- | --- | | Which chains can the spec address? | Effectively any, by chain identifier | | Which chains can you actually pay on? | Those a facilitator and a client both support | | Which chains carry real volume? | A short list, and it moves | The first is nearly unlimited and nearly useless. The protocol takes a network identifier and an asset address; nothing stops you naming any chain. That tells you nothing about whether a payment will go through. The second is the practical answer. You need a facilitator that will settle on that chain and a client library that can build the right authorisation. Both have to exist and support each other. The third is the commercial answer, and it is the one worth checking before choosing. ## What carried volume through 2026 **[Base](https://roundhouseai.io/resources/x402-on-base)** held the cumulative lead for most of the year and remains the chain with the deepest x402 history. It was where the protocol launched and where most tooling was built first. **[Solana](https://roundhouseai.io/resources/x402-on-solana)** grew sharply. Reporting in mid-August 2026 put it at roughly 70% of monthly transaction activity, and an independent tally of 680 x402 services found it at about 74% of measured transactions. Weekly share figures from other trackers were lower, around 38% against Base at 48%. The numbers disagree because they count different things over different windows. **Stellar, Polygon and Avalanche** appear as live settlement rails, reachable through facilitators. Per-chain volume figures for them are thin. One directory count gave Polygon roughly 1,540 transactions and about $1,115 over 30 days from 15 services, which is a small sample and should be read as such. > [!WARNING] > Chain shares in this market are not stable properties. The base is small and concentrated enough that a handful of active sellers moving chain shifts a share by tens of points. Any share figure should be read with its date attached, and a figure more than a month old is history rather than a description of now. ## Why did x402 end up on cheap chains? Arithmetic, not preference. A payment whose price is a tenth of a cent cannot cost more than that to settle. On a chain where a token transfer costs several cents, the cost of taking the payment exceeds the payment, and the business does not exist at any volume. That rules out Ethereum mainnet for the typical x402 price point and makes cheap, fast chains the only viable hosts. [Who pays the gas](https://roundhouseai.io/resources/who-pays-gas-in-x402) covers where that cost lands: the facilitator pays it and prices it in, so it reaches the seller as a fee rather than as a gas bill. ## What changes between EVM and Solana? More than the specification implies, and it matters if you are building either side. On EVM chains the buyer signs an [EIP-3009](https://roundhouseai.io/resources/eip-3009-transfer-with-authorization-explained) authorisation. On Solana there is no EIP-3009, because it is an Ethereum token standard; the equivalent is an SPL token flow where a relayer pays the fee on a transfer the holder authorised. [x402 v2](https://roundhouseai.io/resources/x402-v1-vs-v2-what-changed) generalised the protocol so this is a first-class path rather than an extension. The consequence for a seller is that your client library and facilitator both have to handle the chain you pick, and support is uneven. The consequence for anyone measuring is larger: an index covering both is running two different detectors, which is most of why cross-chain figures disagree so widely. ## How should a seller choose? Three considerations, in this order. **Where are your buyers?** The chain where your likely buyers already hold a stablecoin balance. A buyer that would have to bridge to pay you usually does not pay you. **What does your facilitator support?** Coverage differs per facilitator, so this constrains the choice more than most people expect. Check it before committing. **How visible do you want to be?** Indexers cover chains unevenly. A settlement on a chain nobody indexes is public and invisible at the same time, which matters if you want your activity to be checkable by buyers evaluating you. You can advertise more than one chain in your `accepts` array, and a seller wanting reach should. The cost is a second reconciliation rather than a second integration. ## Frequently asked questions ### Can I use x402 on Ethereum mainnet? Technically yes. Economically only for payments large enough to absorb mainnet gas, which is a different product from the sub-cent calls x402 is mostly used for. ### Does the buyer need to be on the same chain as me? Yes, for a given payment. There is no bridging in the protocol. A buyer holding funds elsewhere either finds another entry in your terms it can satisfy or does not pay. ### Which chain has the best tooling? Base has the longest-established x402 tooling and documentation. Solana's has matured quickly and is now well covered. Beyond those two, expect to read facilitator documentation rather than tutorials. ### Are testnets supported? Yes, and the default facilitator at x402.org is testnet-only, which is deliberate: it exists for development. Note that testnet token contracts can have different EIP-712 domain parameters from mainnet, which is a common first-integration bug. ### Should I pick the chain with the most x402 volume? Not automatically. Volume includes a lot of activity that is not commerce, and your buyers' balances matter more than a leaderboard. [How much of that volume is real](https://roundhouseai.io/resources/how-much-x402-volume-is-real) is worth reading before using it as a signal. ## Where to check this yourself [/stats](https://roundhouseai.io/stats) breaks the indexed record down by chain with the window and basis stated, which is the comparison worth making rather than a pooled total. [/status](https://roundhouseai.io/status) publishes which chains the index covers and how far behind each one it is, so you can tell a chain with no activity from a chain nobody is watching. --- 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