Adding a custom RPC (a custom network) gives your software wallet access to blockchains that aren’t pre-configured, private testnets, Layer 2s, or EVM-compatible sidechains. In my experience, this is the routine step developers and active DeFi users take when they need lower gas fees, faster confirmation times, or to interact with a specific dApp that only runs on a particular chain.
Why do it? Concrete benefits:
And yes, adding a custom RPC is a frequent part of everyday DeFi work when testing contracts or using new L2s.
Make sure you have these pieces of information from the network or node provider:
Also: record the data source (link to official network docs or node provider). If you plan to use a hosted node, note any API key or rate limits.
(If you don’t have these, adding the network will either fail or give inaccurate behavior.)
Here is a concise, step-by-step process for add custom network MetaMask mobile. I followed these steps on both iOS and Android while testing.
Common small-test: send a minimal amount (for tokens use 0.0001 units or the network’s micro amount) to confirm the RPC and explorer mapping.
If a dApp prompts your wallet to add or switch networks, you can approve the request; more on that below.
| Field | Purpose | Example (placeholder) |
|---|---|---|
| RPC URL | The JSON-RPC endpoint MetaMask queries for chain state and to submit transactions. | https://rpc.example.net |
| Chain ID | Decimal identifier that prevents replay across chains (MetaMask expects the network's chain ID). | 137 |
| Currency symbol | Token used to pay gas (display only). | MATIC |
| Block Explorer URL | Links transactions/accounts to a human-readable explorer. | https://explorer.example/tx/ |
A note on Chain ID formatting: if a provider gives a hex value (0x89), convert it to decimal (137). MetaMask reads the decimal form reliably.
You have three common choices for an RPC node:
Which to pick? It depends on measurable needs: if you need <100 requests/day for wallet use, a reliable public or low-tier hosted node suffices. If you run automated tooling, heavy dApp testing, or require privacy, run your own node (see /running-your-own-node and /developer-rpc-and-node-guide).
But remember: hosted nodes introduce a trust/availability trade-off. If you run high-value transactions, reducing third-party dependence by using your own node is a measurable risk reduction.
An RPC endpoint can censor data, misreport balances, modify fee suggestions, or (in extreme cases) tamper with transaction payloads. Do not send private keys or seed phrases to any RPC. MetaMask never requests your seed phrase through RPC, but attackers can host portals that mimic node configuration.
Checklist to reduce risk:
Link to more on backups and recovery here: /seed-phrase-backup-recovery and general security tips at /security-checklist.
dApps can request that your wallet add a chain or switch networks using standard JSON-RPC methods (e.g., wallet_addEthereumChain and wallet_switchEthereumChain). When a dApp uses this, MetaMask will show a confirmation dialog with the proposed RPC details. Always inspect the RPC URL and Chain ID before approving.
If a dApp attempts to switch to a network you’ve added, MetaMask typically asks for confirmation. Switch network MetaMask requests are fast, but network switching may change token visibility and gas fee estimation (test small txs after switching).
If you prefer manual control, add networks yourself via Settings instead of accepting dApp prompts.
If a transaction is stuck or pending after switching RPCs, see /pending-transaction-troubleshooting and /transaction-errors-and-fixes for step-by-step recovery.
Who this is for:
Who should look elsewhere:
Q: Is it safe to keep crypto in a hot wallet?
A: Hot wallets are convenient for active DeFi use. They trade off security for accessibility. For small, daily-usage balances it’s a practical choice. For larger holdings, pair MetaMask with a hardware wallet or move cold storage offline. See /security-checklist for operational steps.
Q: How do I revoke token approvals if I used a custom RPC to interact with a dApp?
A: Use a token approval manager or the wallet’s approvals UI (see /token-allowances-and-revoke). If the dApp was malicious, revoke approvals immediately and move funds if needed.
Q: What happens if I lose my phone after adding custom networks?
A: Your MetaMask setup can be restored on a new device with your seed phrase. Custom networks are metadata — you may need to re-enter RPC details unless you back them up separately. See /seed-phrase-backup-recovery for recovery steps.
Adding custom RPC MetaMask mobile is a routine, low-friction way to access non-default chains and testnets. Follow the step-by-step checklist, verify RPC URLs (and Chain ID decimal values), and always test with small transactions first.
If you want deeper guidance on running your own node or developer-focused RPC configuration, read /developer-rpc-and-node-guide and /running-your-own-node. Ready to try it? Add a test network, record the source of the RPC info, and make a micro transfer to confirm everything works.
But keep security first: never share your seed phrase, and consider hardware wallets for high-value operations.