How we evaluate
A blockchain for AI agent payments is judged on different priorities than a chain for trading or NFTs. The agent makes many small payments programmatically, so the criteria that matter are:
- Transaction fee. The single most important property. An agent paying sub-cent and few-cent amounts needs a fee that is a tiny fraction of the payment, or the economics collapse.
- Finality and speed. A payment should confirm fast enough that the agent does not stall waiting for it mid-task.
- Native stablecoin. Is USDC (or another dollar stablecoin) native and liquid on the chain, so the agent settles in dollars without bridging?
- Tooling and compatibility. EVM compatibility means existing libraries, wallets, and the x402 stack work directly; a different VM means different tooling.
- Security and decentralization. The chain must be secure enough to trust with real value, with credible decentralization behind it.
- Agent-rail support. Does the payment infrastructure you use settle on this chain? A chain your rail does not support is not an option for that rail.
Fees decide it
It is worth stating plainly: for agent payments, fees decide it more than any other factor. A human makes a few payments a day, so a dollar of fee is an annoyance; an agent makes hundreds or thousands, often for sub-cent amounts, so a dollar of fee per transaction makes the entire workload impossible. The chain that wins for agents is the one where settling a five-cent payment costs a fraction of a cent.
That single fact eliminates high-fee chains for the micropayment pattern, regardless of their other merits, and elevates low-fee chains that still offer real security and native stablecoins. Keep this front of mind as you read the options, because a chain can be excellent in every other way and still be wrong for an agent if its fees are high.
The five realistic options
In 2026 the realistic chains for agent payments are Base, Ethereum mainnet, Solana, Polygon, and Arbitrum. They differ most on fees, VM, and which rails settle on them, and the right pick is shaped heavily by the payment infrastructure you build on.
Option 1: Base
Base is an Ethereum Layer 2 built on the OP Stack, with low fees, fast confirmation, and native USDC. For agent payments it is the practical default: the low fee makes micropayments viable, EVM compatibility means the whole tooling stack works, and it is the chain the x402 exact-usdc settlement here runs on, using eip155:8453 for mainnet and eip155:84532 for Base Sepolia.
It fits best when you want low-fee, EVM-native agent payments in USDC, which is the common case, and it is simply the chain you use on this rail. Its main consideration is that, as an L2, it inherits Ethereum security through its rollup design rather than being an independent L1, which is a deliberate trade most agent payment workloads are happy to make for the fees. In practice that trade is the right one for agents: you get near-mainnet security guarantees while paying L2-level fees, which is exactly the combination a high-volume, small-payment workload needs, and it is why so much agent payment activity has settled on Base rather than on the L1 beneath it.
Option 2: Ethereum mainnet
Ethereum mainnet is the most secure and decentralized EVM chain, the settlement layer the L2s build on. Its strength is unmatched security and finality assurance for high-value transactions.
It fits least well for agent micropayments, because its fees make sub-cent and few-cent payments uneconomic. It fits high-value, low-frequency settlement where a fee is negligible against the amount, or as the security root that an L2 like Base settles back to. For the many-small-payments pattern of an agent, use an L2 over mainnet and let mainnet be the security foundation underneath rather than the place you transact.
Option 3: Solana
Solana is a high-throughput, very-low-fee Layer 1 with a non-EVM runtime. Its strength is fees and speed, which suit payments well, and it has strong USDC support.
It fits best when you are already building on Solana and want its low fees and throughput. The consideration for this stack is that it is non-EVM, so it uses different tooling than the EVM x402 stack, and it is not the chain this rail settles on in 2026. Weight Solana when you are a Solana shop and value its performance; weight Base when EVM compatibility and the x402 rail here matter to you.
Option 4: Polygon
Polygon is an established low-fee EVM chain with broad adoption and USDC support. Its strength is a mature ecosystem and low fees, with EVM compatibility that keeps tooling familiar.
It fits well as a low-fee EVM alternative when your existing deployment is there. For agent payments it is viable, but the x402 rail here settles on Base rather than Polygon, so choosing Polygon means either using a different payment path or bridging. Weight it when you already operate on Polygon and want to keep that footprint, and check rail support for your specific payment infrastructure.
Option 5: Arbitrum
Arbitrum is a leading Ethereum L2 with low fees, a large ecosystem, and EVM compatibility. Its strength is a deep DeFi and tooling ecosystem with the low fees of an L2.
It fits well as another low-fee EVM L2 option, comparable to Base on fees and compatibility. As with Polygon, the consideration is rail support: the x402 settlement here is on Base, so Arbitrum suits you when your stack already lives there and your payment infrastructure settles on it. Weight it on ecosystem fit and confirm your rail supports it before committing.
Summary comparison
| Chain | Fee level | VM | Native USDC | x402 rail here | Best fit |
|---|---|---|---|---|---|
| Base | Very low | EVM (L2) | Yes | Yes | Low-fee EVM agent payments, the default |
| Ethereum mainnet | High | EVM (L1) | Yes | No | High-value settlement, security root |
| Solana | Very low | Non-EVM | Yes | No | Solana-native shops |
| Polygon | Low | EVM | Yes | No | Existing Polygon deployments |
| Arbitrum | Low | EVM (L2) | Yes | No | Existing Arbitrum deployments |
How to pick
Start from fees and your rail. If you are building agent payments on x402 with Blockchain0x, the choice is made: Base, which also wins on the criteria for agents anyway, so there is little to deliberate. If your context is broader, lead with the fee question, because it decides whether micropayments work at all, and only then weigh VM and ecosystem.
Choose Base for low-fee EVM agent payments on this rail, Solana when you are a Solana shop valuing throughput, Ethereum mainnet only for high-value low-frequency settlement, and Polygon or Arbitrum when you already operate there and your payment infrastructure settles on them. For the common case of an agent paying per call in USDC, a low-fee chain with native USDC is the requirement, and Base on the x402 rail meets it directly. To see it working, read how-to-add-usdc-payments-to-ai-agent, and pair the chain choice with the unit in best-stablecoin-for-ai-payments. Pricing is on the pricing page.