Transaction Infrastructure
Transactions that land. Every time.
The execution engine under the sponsorship layer: parallel processing, automatic nonce and mempool management, and the best inclusion time in the industry, across 100+ chains.
Your app submits a user operation
Through permissionless.js or any ERC-4337 client.
The engine takes over
Validation, gas estimation, nonce sequencing, and mempool management, all handled in parallel.
Included on-chain
Under 2 seconds on L2s, with automatic resubmission if conditions change.
Reliability
The hard parts are our job, not yours
Everything between “user clicked” and “confirmed on-chain” is handled by the engine.
Parallel execution
User operations process simultaneously across accounts, so a spike in your traffic never queues behind itself.
Nonce & mempool management
Sequencing, gas price escalation, resubmission, and re-org recovery happen automatically.
Every account, every EntryPoint
All official EntryPoint versions and every major smart account implementation, from Safe to Kernel to MetaMask.
100+ chains, one API
The same integration works on Ethereum, every major L2, and the long tail, with new chains added continuously.
SOC 2 & SLAs
SOC 2 Type 1 certified, 24/7 monitoring by a dedicated team, and custom uptime SLAs on Enterprise.
For developers
One client, the whole engine
Submit through permissionless.js, the most widely used smart account library at 100k+ weekly downloads, with bundlerTransport pointed at api.pimlico.io.
Everything in the grid above — validation, gas estimation, nonce sequencing, resubmission — happens behind a single sendTransaction call that returns your transaction hash.
import { createSmartAccountClient } from "permissionless"
import { toSafeSmartAccount } from "permissionless/accounts"
import { createPimlicoClient } from "permissionless/clients/pimlico"
import { http, parseEther } from "viem"
import { base } from "viem/chains"
const pimlicoUrl = "https://api.pimlico.io/v2/base/rpc?apikey=API_KEY"
const pimlicoClient = createPimlicoClient({ transport: http(pimlicoUrl) })
const account = await toSafeSmartAccount({
client: publicClient,
owners: [owner],
version: "1.4.1",
})
// Gas is sponsored, so your user never sees a fee
const smartAccountClient = createSmartAccountClient({
account,
chain: base,
bundlerTransport: http(pimlicoUrl),
paymaster: pimlicoClient,
})
const txHash = await smartAccountClient.sendTransaction({
to: "0x...",
value: parseEther("0.1"),
})A few of the networks the engine runs on
Ethereum
Base
Arbitrum
Optimism
Polygon
BNB Chain
AvalancheIn production
The execution layer other infrastructure trusts
Boosted Sponsorships
34–43% faster, by doing less
Boosted Sponsorships strip the flow down to its fastest possible form: no paymaster data on the operation and three fewer RPC round-trips, making user operations 34–43% faster end to end.
You settle by monthly invoice instead of per-operation on-chain deduction. Access is granted on request.
Your app submits a user operation
No paymaster data to fetch, no extra signature round-trips.
Pimlico sponsors off-chain
Three RPC calls disappear from the hot path entirely.
Settled by invoice
Gas is billed monthly instead of deducted on-chain per operation.
Developer platform
The tooling around the engine
Production infrastructure is more than an RPC endpoint. Everything you need to operate, debug, and lock down sponsorship is built in.
Run it in production
Watch every operation land, end to end
Every user operation is traceable in the dashboard from the moment it arrives: received, added to the mempool, submitted, and included on-chain, with millisecond timings and transaction hashes at every step.
When someone asks where a transaction went, you answer in seconds, not by grepping logs.
Track user operation
Received
2026-06-11 20:01:13.054
Added to Mempool
2026-06-11 20:01:13.054 (+0ms)
Submitted
2026-06-11 20:01:13.341 (+287ms)
Tx Hash: 0x223b701f...Included Onchain
2026-06-11 20:01:13.590 (+249ms)
Tx Hash: 0x223b701f...Open source
Powered by Alto, in the open
The engine isn't a black box. Alto, our open-source bundler, is the backbone of everything Pimlico runs in production, hardened by 250M+ real transactions.
The same goes for permissionless.js, the client you integrate: both ends of the pipeline are in the open.
We also co-authored the standards this industry builds on: ERC-4337, ERC-7677, and ERC-7679.
Up the stack
The sponsorship layer on top
Reliable execution is half the engine. The same API sponsors gas, accepts ERC-20 fees, and enforces policy — which is why teams choose hosted Pimlico over self-hosting.
Frequently asked questions
Is this an ERC-4337 bundler?
Yes. Under the hood this is Pimlico’s ERC-4337 bundler service, powered by our open-source bundler Alto. It supports every official EntryPoint version and all major smart account implementations.
What does "<2s inclusion" mean exactly?
On L2 chains, the time between submitting a user operation and it landing on-chain averages under two seconds, typically next-block inclusion. It is the best inclusion time in the industry.
How do you handle transaction failures and re-orgs?
The engine manages nonce queues, gas price escalation, resubmission, and re-org detection automatically. Hundreds of user operations process in parallel without blocking each other.
Can I run the bundler myself?
Alto is open source and you are free to run it. Teams use Pimlico’s hosted infrastructure for the multi-chain coverage, monitoring, SLAs, and the sponsorship engine on top.
What does the hosted service cost?
Free on testnets, pay-as-you-go in production with a monthly credit allowance included and no monthly minimum. Enterprise plans add lower pre-paid rates and custom SLAs.
See pricing