> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mrdn.finance/llms.txt
> Use this file to discover all available pages before exploring further.

# Supported Networks

> Networks supported by Meridian

## Overview

Meridian supports multiple EVM networks with different levels of functionality for each network. This page documents the current network support and capabilities.

## Contract Addresses

### Mainnet

| Network      | Chain ID | Payment Token                                | Facilitator                                  | Cross-chain |
| ------------ | -------- | -------------------------------------------- | -------------------------------------------- | ----------- |
| `avalanche`  | `43114`  | `0xB97EF9Ef8734C71904D8002F8b6Bc66Dd9c48a6E` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | No          |
| `base`       | `8453`   | `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | Across      |
| `bsc`        | `56`     | `0x8AC76a51cc950d9822D68b83fE1Ad97B32Cd580d` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | Across      |
| `bot-chain`  | `677`    | `0xaBabc7Ddc03e501d190C676BF3d92ef0e6e87a3C` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | No          |
| `optimism`   | `10`     | `0x0b2C639c533813f4Aa9D7837CAf62653d097Ff85` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | Across      |
| `arbitrum`   | `42161`  | `0xaf88d065e77c8cC2239327C5EDb3A432268e5831` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | Across      |
| `polygon`    | `137`    | `0x3c499c542cef5e3811e1192ce70d8cc03d5c3359` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | Across      |
| `unichain`   | `130`    | `0x078d782b760474a361dda0af3839290b0ef57ad6` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | Across      |
| `ink`        | `57073`  | `0x2D270e6886d130D724215A266106e6832161EAEd` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | Across      |
| `worldchain` | `480`    | `0x79A02482A880bCe3F13E09da970dC34dB4cD24D1` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | Across      |
| `sei`        | `1329`   | `0xe15fC38F6D8c56aF07bbCBe3BAf5708A2Bf42392` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | No          |
| `hyperevm`   | `999`    | `0xb88339CB7199b77E23DB6E890353E22632Ba630f` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | Across      |
| `megaeth`    | `4326`   | `0xFAfDdbb3FC7688494971a79cc65DCa3EF82079E7` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | No          |
| `tempo`      | `4217`   | `0x20C000000000000000000000b9537d11c60E8b50` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | No          |
| `monad`      | `143`    | `0x754704Bc059F8C67012fEd69BC8A327a5aafb603` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | Across      |
| `robinhood`  | `4663`   | `0x5fc5360D0400a0Fd4f2af552ADD042D716F1d168` | `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6` | Across      |

#### Non-EIP-3009 Token Note

Chains whose payment token does not natively support EIP-3009 use Permit2 via
`x402ExactPermit2Proxy` `0x402085c248EeA27D92E8b30b2C58ed07f9E20001`. This is
the canonical exact Permit2 proxy from the official
[x402 repository](https://github.com/x402-foundation/x402/tree/main), deployed
at the same address on supported EVM chains. This includes MegaETH, BSC, and
BOT chain testnet and mainnet.

For these integrations:

* Keep `payTo` set to the facilitator `0x8E7769D440b3460b92159Dd9C6D17302b036e2d6`
* Set `paymentRequirements.asset` to the ERC-20 token address the buyer will pay with
* Use Permit2 `0x000000000022D473030F116dDEE9F6B43aC78BA3` as the approval target
* Use `x402ExactPermit2Proxy` `0x402085c248EeA27D92E8b30b2C58ed07f9E20001` as the Permit2 spender

#### Upto Scheme Note

The `upto` scheme (usage-based pricing, buyer signs a maximum and the seller
settles the actual amount) is available on **every** supported network, since
it always settles via Permit2. Sign with `x402UptoPermit2Proxy`
`0x402015c795ecb48A360bDC6e35a2EaEb313a0002` as the Permit2 spender (same
address on every chain) and include the `facilitator` field in the witness. See
[Payment Types](/api-reference/payment-types/overview) for details.

#### Tempo Note

Tempo has no native gas token. Transaction fees are paid in TIP-20 stablecoins such as USDC.e. Meridian uses USDC.e at `0x20C000000000000000000000b9537d11c60E8b50` for payment flows. The public RPC is `https://rpc.tempo.xyz`, the WebSocket endpoint is `wss://rpc.tempo.xyz`, the explorer is `https://explore.tempo.xyz`, and Circle CCTP/Gateway is not currently supported.

### Testnet

| Network             | Chain ID   | Payment Token                                | Facilitator                                                                                                                       | Cross-chain |
| ------------------- | ---------- | -------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------- | ----------- |
| `arc-testnet`       | `5042002`  | `0x3600000000000000000000000000000000000000` | [`0x8e633dBf31adCc7D41BE3e95B7c8DD3526B5235A`](https://testnet.arcscan.app/address/0x8e633dBf31adCc7D41BE3e95B7c8DD3526B5235A)    | No          |
| `bot-chain-testnet` | `968`      | `0x75edC9335175Fc0552D51D48439F229c10420fe3` | `0x8e633dBf31adCc7D41BE3e95B7c8DD3526B5235A`                                                                                      | No          |
| `base-sepolia`      | `84532`    | `0x036CbD53842c5426634e7929541eC2318f3dCF7e` | `0x8e633dBf31adCc7D41BE3e95B7c8DD3526B5235A`                                                                                      | Across      |
| `fluent-testnet`    | `20994`    | `0xa5544e6DDe3d8927Bf3bD9556e84f49067E36bAf` | [`0xB3Ac1B7871942bCdCD0bD6C65765272bBE70B8Da`](https://testnet.fluentscan.xyz/address/0xB3Ac1B7871942bCdCD0bD6C65765272bBE70B8Da) | No          |
| `optimism-sepolia`  | `11155420` | `0x5fd84259d66Cd46123540766Be93DFE6D43130D7` | `0x8e633dBf31adCc7D41BE3e95B7c8DD3526B5235A`                                                                                      | Across      |

Fluent testnet currently uses a mock USDC deployment, including function `mint(to, amount)` to receive test USDC.

#### Arc Testnet Note

Arc Testnet uses USDC as the native gas token. Meridian uses the ERC-20 USDC interface at `0x3600000000000000000000000000000000000000` for payment flows. The public RPC is `https://rpc.testnet.arc.network`, the WebSocket endpoint is `wss://rpc.testnet.arc.network`, the explorer is `https://testnet.arcscan.app`, and the Circle CCTP/Gateway domain is `26`.

### Solana (SVM)

Meridian settles USDC payments on Solana through the `meridian_x402` program
rather than an EVM facilitator. Payments are same-chain only (no Across
cross-chain routing on Solana in this version).

| Network         | Cluster      | USDC Mint                                      | Program ID                                    |
| --------------- | ------------ | ---------------------------------------------- | --------------------------------------------- |
| `solana`        | mainnet-beta | `EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v` | `Ro6hz1smrm5zDh73849eDqKna9dE1EkPsWekAB5rBWm` |
| `solana-devnet` | devnet       | `4zMMC9srt5Ri5X14GAgXhaHii3GnPAEERYPJgZJDncDU` | `Ro6hz1smrm5zDh73849eDqKna9dE1EkPsWekAB5rBWm` |

The program is live on both `solana` and `solana-devnet`. Do not
hardcode the program ID or the fee-payer pubkey — read everything at runtime
from `GET /v1/solana/facilitator?network=<network>`, which returns
`{ network, facilitator, programId, configPda }` plus the on-chain program
config (`usdcMint`, `treasury`, `treasuryToken`, `treasuryFeeBps`, `paused`)
when the chain is reachable. Buyers need no Anchor, no IDL, and no on-chain
config reads — this one call plus `@solana/web3.js` / `@solana/spl-token` is
enough. For these integrations:

* Set `paymentRequirements.asset` to the **USDC mint** address
* Set `paymentRequirements.payTo` to the seller's **recipient wallet** (owner,
  not a token account), matching the org's configured Solana recipient
* Set `paymentRequirements.extra.feePayer` to the facilitator pubkey; the buyer
  signs the settlement transaction and the facilitator co-signs as fee payer
* Ensure all USDC associated token accounts exist before settlement

See [Solana Program](/payments/solana-program) and the
[Solana payments](/ai-skills/solana) integration guide.

## Network Monitoring

* Monitor network status via `/v1/supported` endpoint
* Implement fallback logic for network outages
* Cache network information with appropriate TTL