A user controls assets across multiple blockchain ecosystems—Solana, Ethereum, Base, and several smaller or emerging chains—but relies on a single wallet interface. Phantom Wallet provides native support for major networks, yet application developers, enterprise deployments, and protocol communities frequently operate on networks not immediately visible in the wallet’s default configuration. The practical question is straightforward: how do you safely add a custom network to your phantom wallet without exposing credentials, misconfiguring RPC endpoints, or routing transactions to a spoofed chain?
The answer requires understanding both the technical mechanics and the verification steps that separate a legitimate network addition from a social engineering attack. Phantom Wallet is a non-custodial, self-custodial wallet where users maintain full control through a twelve-word Secret Recovery Phrase. That control extends to network configuration: adding a custom blockchain means explicitly trusting an RPC provider and ensuring that your wallet can communicate with the correct chain. The process is accessible to experienced users but demands attention to detail, because a misconfigured endpoint can lead to transactions broadcast to an unintended destination or funds sent to an address on a different network than expected.
Understanding RPC endpoints and chain identity
An RPC endpoint is a server that translates your wallet’s requests into blockchain queries and broadcasts your signed transactions to the network. When you add a custom network to a multichain wallet like Phantom, you are specifying which server should handle that communication. The critical detail is that the endpoint must correspond to the correct chain. If you provide an Ethereum RPC URL but the wallet believes it is connected to a test network, or if an attacker redirects you to a malicious endpoint, your signed transaction could arrive at an unexpected destination.
Each blockchain is identified by a unique chain ID, a numerical value encoded in the transaction signature itself. This prevents a transaction signed for Ethereum from being replayed on a different EVM-compatible chain. When you add a custom network to Phantom Wallet, the chain ID you specify must match the actual network’s chain ID. If they do not match, the wallet may reject the transaction or, worse, allow it through to a different network. This is not a display bug; it is a cryptographic boundary. Solana uses a different signature scheme than Ethereum-compatible chains, so the wallet must also know the network type to construct and validate transactions correctly.
RPC endpoints come in several categories. Public endpoints operated by the blockchain foundation or community members are free but often rate-limited and may have higher latency. Private endpoints from providers such as Alchemy, Infura, QuickNode, or others offer higher reliability and throughput but typically require registration and may involve fees. A testnet endpoint for a development chain will have different transaction history and token balances than the mainnet. Before adding any custom network, verify which endpoint class you are using and whether you intend to conduct real transactions or testing.
The URL structure matters as well. An RPC endpoint is not simply a server IP; it is a complete URL path that often includes an API key or authentication mechanism. Phantom Wallet will send your requests to that URL verbatim. A typo or truncated URL may route requests to a different service entirely. Public endpoints may work without authentication, but they often have request limits. If your wallet hits those limits, transactions may fail or be queued indefinitely. For production use, a dedicated or premium endpoint is typically more reliable than relying on a shared public resource.
Adding an EVM-compatible custom network
Most custom networks that users add to Phantom Wallet are EVM-compatible, meaning they implement the same transaction and smart contract interface as Ethereum but operate as independent blockchains. Adding one requires opening the Phantom settings, navigating to the networks section, and selecting the option to add a custom network. The wallet will prompt you for several fields: a display name for the network, the RPC endpoint URL, the chain ID, a currency symbol for the native token, and optionally a block explorer URL.
The process begins with research. Find the official documentation or governance resources for the chain you want to add. Mainnet and testnet chains usually have published RPC endpoints; blockchain foundations or community maintainers provide the correct chain ID, currency symbol, and block explorer. For example, if you are adding a layer-2 rollup or sidechain, the project’s official website or GitHub repository should list these details. Do not copy configuration from an untrusted source, a random forum post, or a link shared in a social media message. Phantom Wallet cannot verify whether an endpoint is legitimate, so that responsibility falls entirely on the user.
Once you have gathered the correct details, open Phantom and navigate to the settings menu. Look for a “Networks” or “Custom Networks” option. The exact menu structure may vary between the mobile app and browser extension, but the principle is identical. Select “Add Network” and fill in each field carefully. The display name is purely for your own reference; choose something you will recognize. The RPC endpoint must be the complete URL provided by the endpoint operator. The chain ID should be a number matching the official specification—copying the wrong digit invalidates the configuration. The currency symbol is typically a 3–6 letter abbreviation for the native token. If available, the block explorer URL allows Phantom to generate links to transaction details and addresses on that chain’s public record.
After entering the details, save the network. Phantom Wallet will not immediately test the connection; it trusts your input. At this point, you should perform a manual verification before conducting real transactions. Open the block explorer URL directly in your browser and check the most recent block number and timestamp. In your wallet, if the network connection is working, create a transaction preview—do not broadcast it yet—and confirm that the displayed chain ID, gas estimate, and other parameters match what you expect. Only after that verification should you send a small test transaction on the custom network. If it succeeds and arrives at the expected address, the network is configured correctly.
Configuring non-EVM custom networks
Non-EVM networks, such as Solana and Sui, use different transaction formats and signature schemes than Ethereum-compatible chains. Phantom Wallet already includes native support for Solana and other major networks, so adding a custom non-EVM chain is less common but sometimes necessary for testnets or alternative implementations. The process differs because the wallet must construct transactions in the non-EVM format and validate results accordingly.
Phantom Wallet manages credentials rather than holding private keys directly, meaning the wallet derives network-specific addresses from your Secret Recovery Phrase. For Solana, that address is a base-58 encoded string; for Ethereum, it is a 0x-prefixed hexadecimal address; for Sui, it follows Sui’s naming convention. When you add a custom non-EVM network, the wallet must know how to generate the correct address format. If the custom network uses Solana’s signature scheme, it will use your Solana derivation path. If it uses a different scheme entirely, compatibility becomes a question that depends on how Phantom Wallet treats the network type you specify.
For a custom non-EVM network, research is even more critical. The network documentation must specify the exact RPC endpoint format, the address derivation standard it expects, and any testnet tokens available for testing. Some networks have their own wallet libraries that Phantom may not yet support natively. In that case, the network may not be compatible with Phantom Wallet at all, and using it would require a different wallet application entirely. Before attempting to add a custom non-EVM network, confirm in Phantom’s official documentation or GitHub issues whether the wallet supports adding networks of that type. If support is limited, you may need to use a network-specific wallet in parallel.
If Phantom does support adding custom networks of a particular non-EVM type, the process is similar to EVM configuration: gather the official RPC endpoint, understand the address format, note any relevant identifiers the network uses, and enter them into the wallet’s custom network interface. Verify the address generation by comparing your wallet’s displayed address to what a network explorer shows. Test with a small transaction. If the transaction succeeds and arrives correctly, the network is properly configured. If it fails, double-check the RPC endpoint URL and the address format before retrying.
Identifying and avoiding spoofed or malicious endpoints
A phantom wallet is only as secure as the networks it trusts. An attacker could create a fraudulent RPC endpoint that mimics a legitimate network or even a popular existing chain. If you connect to that endpoint, your signed transactions could be routed to a different network, stolen, or modified. Phantom Wallet provides several defenses, but they depend on how carefully you configure the network and verify the address.
The first defense is transaction preview. Before signing any transaction on a custom network, Phantom Wallet should display a preview showing the sender address, recipient address, amount, gas fee, and chain ID. Examine this preview carefully. If the chain ID matches what you specified and the recipient address is correct, the transaction is likely genuine. If the preview shows a different chain ID or a recipient address you do not recognize, stop immediately. Do not sign the transaction. This is where a strong habit of reading every field—not just clicking “approve”—saves funds.
The second defense is block explorer verification. After adding a custom network to a phantom wallet, open the block explorer URL directly in your browser and verify that it displays current data. If the block explorer shows a chain halted at an old block height, is inaccessible, or displays fake transactions, the RPC endpoint and explorer may both be compromised. Legitimate networks have actively maintained explorers that show recent activity. If the explorer appears stale or suspicious, remove the network from your wallet and investigate further before proceeding.
The third defense is address consistency. When you add a custom network, Phantom derives an address based on your Secret Recovery Phrase and the network’s expected derivation path. If the same address appears in multiple legitimate sources—the wallet display, the block explorer, and external documentation—that is a positive signal. If the address differs between sources or if you see it on a network you did not expect, investigate immediately. Some networks may intentionally use the same address format as Ethereum for convenience, but the underlying chain remains separate.
Social engineering is also a risk. Attackers may post instructions to add a “limited-time” or “exclusive” network, claiming special yield or rewards. Official communications from blockchain projects should come through their verified channels: official websites, published GitHub repositories, or verified social media accounts with verification marks. If you encounter network configuration instructions in a private message, through a Discord bot, or from an unverified source, treat them with extreme skepticism. The cost of verifying legitimate configuration details is far lower than recovering from a compromised wallet or redirected transaction.
Troubleshooting connection and transaction issues
After adding a custom network to Phantom Wallet, you may encounter connection failures, gas estimation errors, or transactions that hang pending. These problems usually stem from RPC endpoint issues, network misconfiguration, or temporary blockchain congestion. Diagnosing them requires methodical testing rather than repeated retry attempts.
If the wallet cannot connect to a custom network, the first step is to verify the RPC endpoint URL directly. Copy the endpoint URL and paste it into your browser, appending a simple JSON-RPC test query. For example, for an EVM-compatible chain, you might add the query {"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1} to test whether the endpoint responds. If the endpoint is down, rate-limited, or invalid, the browser will fail to connect or return an error. In that case, try a different public endpoint or contact the network’s support channels to confirm the issue.
If the wallet connects but gas estimation fails, the RPC endpoint may not support the required methods or may be configured for a different network than you specified. Try creating a transaction preview again; if it fails consistently, the endpoint configuration may be incorrect. Verify the chain ID and RPC URL once more against the official network documentation. If they match but gas estimation still fails, switch to a different RPC endpoint if one is available.
Pending transactions are a separate issue. If you broadcast a transaction to a custom network and it remains unconfirmed for hours, the network may be experiencing congestion or your gas price may be too low. For EVM-compatible chains, you can check the transaction status on the block explorer using the transaction hash. If the transaction appears on the explorer but remains unconfirmed, the network or your node may be overloaded. For non-EVM networks, check the network’s block explorer or status page. If the network is operational but your transaction is stuck, you may need to resubmit with a higher gas price or wait for network congestion to clear. Phantom Wallet does not provide automatic resubmission for custom networks, so patience or manual retries may be necessary.
Best practices for long-term custom network management
Once you have successfully added and tested a custom network on your phantom wallet, maintain good practices to avoid future complications. Keep a record of each network you have added—name, RPC endpoint, chain ID, and the date added—in a private document. This serves as a backup if you need to restore the wallet or reconfigure the network. If an RPC endpoint becomes unavailable, you can quickly switch to a backup endpoint using your documented details.
Monitor the networks you use. If a custom network is abandoned by its development team, the RPC endpoint may go offline without warning. Transactions could fail or be lost. Periodically check the block explorer to confirm the network is still active and producing blocks. If you notice that a network has stopped advancing, do not conduct new transactions until you have confirmed it is operational again.
Update your RPC endpoints when newer ones become available. If you are using a public endpoint that is frequently rate-limited, switching to a private or premium endpoint can improve reliability. Conversely, if you are paying for a premium endpoint but your usage is minimal, a public endpoint may suffice. Adjust your configuration based on your actual usage and budget.
Regularly review the networks in your wallet. If you added a testnet for development and no longer use it, remove it to reduce clutter and minimize the chance of accidentally sending funds to the wrong network. The fewer networks in your wallet, the less opportunity for confusion when you are approving a transaction. This is a small but meaningful risk reduction.
Finally, treat your Secret Recovery Phrase with even greater care once you have customized your wallet. A twelve-word phrase that controls multiple networks and custom chains is more valuable than one tied to standard networks alone. If someone obtains your phrase, they can drain assets across all networks you have configured. Store the phrase offline, consider using a hardware wallet to sign transactions, and never type it into any application or website unless you are absolutely certain it is the legitimate recovery process. The features and flexibility of a customized multichain wallet are only valuable if your underlying credentials remain secure.
When to use alternatives to custom networks
Adding custom networks to Phantom Wallet is powerful, but it is not always the best approach. For blockchain testnets, development chains, or very new networks with minimal liquidity, using a separate wallet application designed specifically for that chain may be safer. Some networks provide their own wallet software that has been thoroughly audited for that specific chain. If you are performing significant development or testing, using a dedicated development wallet rather than your main phantom wallet reduces the risk of accidentally mixing production and test assets.
For networks with very small transaction volumes or immature RPC infrastructure, the reliability and security considerations may differ. A custom network that relies on a single RPC endpoint operated by an unknown entity is higher-risk than one backed by a consortium of providers. Similarly, if a network does not have an actively maintained block explorer or clear documentation, adding it to your wallet introduces additional verification burden. You should only add custom networks where you can independently verify the configuration and maintain confidence in the endpoint operator.
Bridge transactions between networks are another consideration. If you need to move assets from a custom network to Ethereum or another major chain, and a trusted bridge service exists, it is often safer to use that bridge than to manually manage addresses and endpoints. Bridges introduced their own risks and trust assumptions, but a well-audited bridge may provide better protection than a custom endpoint configuration you are uncertain about. Research whether an established bridge, swap aggregator, or routing service already supports the networks you need before assuming that custom network configuration is necessary.
Frequently asked questions
Can I add any blockchain network to Phantom Wallet?
Phantom Wallet supports adding EVM-compatible custom networks directly. Some non-EVM networks may be supported depending on whether Phantom has implemented the necessary signature and address derivation logic. Check the official Phantom documentation or GitHub to confirm whether the specific network type you want to add is supported before attempting configuration. Even if it is technically possible, you should verify that the network is legitimate and the RPC endpoint is reliable before conducting real transactions.
What happens if I enter the wrong chain ID when adding a custom network?
If the chain ID in your wallet configuration does not match the actual blockchain’s chain ID, transactions you sign may be invalid or could be replayed on a different network. The wallet will still allow you to create and sign transactions, but they may fail when broadcast or be accepted by an unintended chain. This is why verifying the chain ID against official documentation before adding a network is critical. If you discover a mismatch after adding the network, delete the custom network and reconfigure it with the correct chain ID.
How do I know if a custom RPC endpoint is secure?
Verify the RPC endpoint by testing it directly in your browser and comparing it to official sources listed on the blockchain’s website or GitHub repository. Check that the endpoint returns current block data and has not been suspended. After adding it to your phantom wallet, examine transaction previews carefully before signing. Use a block explorer to verify that your transactions arrive at the expected addresses. If an endpoint is unfamiliar or comes from an untrusted source, use a different one or contact the blockchain’s support channels to confirm legitimacy.
