Testnet Sponsorship

On testnets you can try sponsorship without a dashboard API key. Use the staging MEE environment and Biconomy’s shared testnet gas tank. No dashboard configuration, no API key with sponsorship enabled, and no billing setup required.

For general testnet setup (staging node URL, supported chains, limitations), see Working with Testnets.

Testnet setup (no API key)

Use the SDK helpers getDefaultMEENetworkUrl and getDefaultMEENetworkApiKey with true to point to the staging environment where all supported testnets are available:

import {
  createMeeClient,
  getDefaultMEENetworkUrl,
  getDefaultMEENetworkApiKey,
  getDefaultMeeGasTank,
  toMultichainNexusAccount,
  getMEEVersion,
  MEEVersion
} from "@biconomy/abstractjs";
import { http } from "viem";
import { baseSepolia } from "viem/chains";

const account = await toMultichainNexusAccount({
  signer,
  chainConfigurations: [
    { chain: baseSepolia, transport: http(), version: getMEEVersion(MEEVersion.V2_1_0) }
  ]
});

const meeClient = await createMeeClient({
  account,
  url: getDefaultMEENetworkUrl(true),
  apiKey: getDefaultMEENetworkApiKey(true)
});

Execute sponsored supertransaction on testnet

When executing, pass sponsorship: true and use the same staging URL and shared gas tank via sponsorshipOptions:

const result = await meeClient.execute({
  instructions: [dummyInstruction],
  sponsorship: true,
  sponsorshipOptions: {
    url: getDefaultMEENetworkUrl(true),
    gasTank: getDefaultMeeGasTank(true)
  },
});

getDefaultMeeGasTank(true) returns the testnet sponsorship gas tank used by the staging environment.

Active testnets (staging)

The following testnet chains support sponsored transactions on staging:

Chain	Chain ID
Arc Testnet	5042002
Avalanche Fuji Testnet	43113
Base Sepolia	84532
Chiliz Spicy Testnet	88882
Fluent Testnet	20994
Mocaverse Testnet	222888
OP Sepolia	11155420
Plasma Testnet	9746
Sei Testnet	1328
Sepolia	11155111
Sonic Testnet	14601
World Chain Sepolia	4801

Quickstart repos

You can run sponsorship on testnets with zero config using these quickstarts. Clone, install, and run—no API keys or private keys required:

Chiliz Spicy Testnet — git clone https://github.com/bcnmy/chiliz-spicy-quickstart.git then bun i and bun run index.ts

This example uses Nexus smart account and MEE supertransaction sponsorship (gasless) on staging.

Moving to production

When you’re ready for mainnet, sponsorship does require dashboard setup. See Sponsor Gas for the full production configuration steps.

Getting Started

Billing

Examples

Testnet setup (no API key)

Execute sponsored supertransaction on testnet

Active testnets (staging)

Quickstart repos

Moving to production

​Testnet setup (no API key)

​Execute sponsored supertransaction on testnet

​Active testnets (staging)

​Quickstart repos

​Moving to production

Testnet setup (no API key)

Execute sponsored supertransaction on testnet

Active testnets (staging)

Quickstart repos

Moving to production