How to Use a Polygon RPC Endpoint in 2026

A Polygon RPC endpoint is a connection point between an app and a Polygon blockchain node. Your wallet, website or script sends requests to the endpoint; it returns information such as the latest block, token balances or transaction receipts. Apps also use RPC to submit transactions that have already been signed by a wallet.

RPC commonly means Remote Procedure Call. Polygon PoS supports Ethereum-compatible JSON-RPC, so many tools designed for Ethereum can communicate with it when configured for the right network. An endpoint is usually provided as a web address by an RPC service or by an organization operating its own node. Treat it as a service address, not as a wallet address.

Using an endpoint does not give it custody of your assets. Your wallet remains responsible for signing transactions. However, an endpoint can affect what your app sees: an unavailable service can block requests, and a dishonest service could return inaccurate information. For significant transactions, verify the chain and transaction details in more than one trusted place.

This guide focuses on Polygon PoS, the network commonly meant by “Polygon” in wallet settings. Polygon also has other networks, including Polygon zkEVM. They are distinct networks and require their own endpoint and network configuration.

Before adding an endpoint, identify the network your app needs. Polygon PoS mainnet is the live network for ordinary onchain activity. Its chain ID is 137. Polygon PoS test networks are for development and testing; their chain IDs and available services differ from mainnet. Polygon zkEVM is a separate network and should not be configured using Polygon PoS details.

Ask the dApp, wallet, developer documentation or RPC provider which Polygon network the endpoint serves. Then compare that information with the network’s published configuration. Do not assume that an endpoint labeled simply “Polygon” is the one you need. Check the network name, chain ID, native gas token details and, where applicable, the network’s block explorer information.

Chain ID is especially useful as a check, but it is not proof that an endpoint is trustworthy. A server can claim to serve a particular chain while still being unreliable. Use a provider you recognize, and cross-check important network information through independent documentation.

If you are building an app, keep separate configuration for mainnet and testing. This helps prevent accidentally sending a transaction to a live network while experimenting. Label each environment clearly, and ensure the endpoint, chain ID and any explorer configuration all describe the same network.

Most users get an endpoint from an RPC provider. A provider may offer a free tier, an account-based service, or a paid plan. Limits and terms vary, so check the provider’s current documentation for request quotas, supported methods, authentication requirements and availability. Public endpoints can be convenient for basic use, but may impose rate limits or become unavailable under heavy demand.

A quick setup generally looks like this:

1. Choose a provider that explicitly supports Polygon PoS and the network you need.
2. Create an account if the provider requires one.
3. In its dashboard or documentation, select the network and copy the endpoint address.
4. Keep any access token or API key private. Treat a key embedded in a browser app as potentially visible to users.
5. Test the endpoint with a harmless read request before connecting it to a wallet or application.

For a team or production app, consider reliability, support, privacy, usage limits and whether the provider offers monitoring or failover. Some developers operate their own node, which offers more control but requires infrastructure, maintenance and operational expertise.

Never use an endpoint merely because it appears in an unsolicited message. Check the provider’s identity and make sure the address is copied from a trusted, official source. If an endpoint stops working, consult the provider’s status information or documentation rather than searching for an unverified replacement.

A custom RPC connection in a wallet changes how the wallet reads blockchain data and sends requests. It does not transfer your assets to the RPC provider. Wallet menus differ, but the process is usually similar:

1. Open the wallet’s network settings and choose its option to add a custom network.
2. Enter a clear network name, such as Polygon PoS Mainnet.
3. Paste the endpoint supplied by your provider into the RPC URL field.
4. Enter chain ID 137 for Polygon PoS mainnet. Confirm the native currency and block explorer details against trusted network documentation or the wallet’s guidance.
5. Save the network, select it, and check that the wallet shows the expected network before interacting with a dApp.

If the wallet warns that the chain ID does not match, stop and recheck the endpoint and network selection. Do not dismiss a mismatch just to make setup complete. When you switch networks, your wallet may display different balances or assets because each network has its own ledger; the same address can exist on multiple networks without the assets being interchangeable.

You can remove or replace a custom endpoint in network settings. Changing the RPC does not change your wallet address or keys. If a dApp asks you to connect, review its network request and transaction details in the wallet before approving anything.

For a basic check, use an API client or command-line tool that can send an HTTP POST request. Set the request content type to JSON and send a standard JSON-RPC method. Replace YOUR_RPC_ENDPOINT with the endpoint address from your provider; it is a placeholder, not a usable server address.

curl -X POST 'YOUR_RPC_ENDPOINT' \\
 -H 'Content-Type: application/json' \\
 --data '{"jsonrpc":"2.0","method":"eth_chainId","params":[],"id":1}'

A successful response includes a result containing the chain ID in hexadecimal. For Polygon PoS mainnet, it should correspond to decimal 137. If the request returns an error, check that the endpoint is copied correctly, supports HTTP JSON-RPC and does not require an authentication header you have omitted.

You can also query the latest block using eth_blockNumber, which returns a hexadecimal block number. A request such as eth_getBalance can read an address’s native-token balance, but requires an address and a block tag such as latest. These are read requests: they do not authorize a transfer.

Avoid putting secrets in command history or shared logs. If your provider embeds an API key in the endpoint address, redact it before sharing diagnostic output. For production code, use a JSON-RPC library where possible, handle errors and timeouts, and avoid assuming that every request will succeed.

In an application, configure the Polygon endpoint as the provider or RPC URL for the network. Ethereum-compatible libraries commonly provide a JSON-RPC provider or client that accepts an endpoint address. The exact constructor and configuration depend on the library and version, so follow that library’s documentation and set the chain ID to match the endpoint.

Keep endpoint configuration outside the main application logic. For example, store it in an environment variable on a server and load it when the app starts. This makes it easier to change providers without editing application code. If an endpoint contains a private service key, do not commit it to a public repository or ship it in front-end code under the assumption that it will remain secret.

Use separate settings for local development, test networks and mainnet. At startup, verify the connected chain ID before allowing an operation that depends on a particular network. For transactions, have a wallet or secure signer create the signature; an RPC endpoint is for communication and is not a substitute for secure key management.

Plan for failures. Set reasonable timeouts, handle JSON-RPC error responses, and consider a fallback endpoint from a separate provider for read operations. Before sending a transaction, ensure the fallback is on the same chain. A request succeeding at the HTTP level does not necessarily mean the JSON-RPC operation succeeded; inspect the response body for an error or result.

Polygon RPC supports standard Ethereum JSON-RPC methods. Read methods retrieve chain data, while transaction-related methods can broadcast signed transactions or interact with a node’s transaction pool. Common examples include:

Method	Typical use
eth_chainId	Check the connected chain ID
eth_blockNumber	Read the latest block number known to the endpoint
eth_getBalance	Read a native-token balance for an address
eth_getTransactionReceipt	Check a transaction’s receipt and execution status
eth_call	Run a read-only contract call without submitting a transaction
eth_sendRawTransaction	Submit a signed transaction for broadcasting

A block number or balance returned by an RPC endpoint is the endpoint’s view of the chain at the time of the request. If the value is important, check it against a separate trusted endpoint or a block explorer. Indexers and explorers may update at different speeds, so small timing differences are possible.

A transaction hash returned after broadcasting does not mean the transaction has completed successfully. Query its receipt and review its status. A reverted transaction may still have consumed gas. Likewise, a read-only contract call does not change state, but its result depends on the contract, input data and block being queried. Use official library documentation for method parameters and response formats rather than constructing complex requests from guesswork.

Troubleshoot in order, starting with the network and endpoint:

• Connection timeout or refused request: Check for a copying mistake, provider outage, network issue or wrong request format. Confirm whether the provider requires authentication.
• Rate limit or quota error: Review your provider’s usage limits and retry guidance. Reduce repeated polling or use an appropriate subscription or indexing service if your app needs frequent updates.
• Wrong chain ID: Confirm whether you selected Polygon PoS, a test network or Polygon zkEVM. Match the endpoint and chain configuration; do not treat different Polygon networks as interchangeable.
• A wallet shows no expected balance: Check that it is on the right network and that the asset exists on that network. An address may have different balances across chains.
• A transaction is pending: Check its hash and receipt through a trusted source. The endpoint may be behind, or the transaction may not yet have been included in a block.
• A method is unsupported: The provider may restrict certain methods or not support subscriptions through the connection type you are using.

An HTTP success code alone does not guarantee a successful RPC call. Read the JSON response for either a result or an error object. For persistent issues, compare the same harmless request against another reputable endpoint and consult your provider’s documentation or status page.

An RPC endpoint can observe the requests sent through it, including queried addresses and the timing of requests. A provider may also collect connection metadata according to its own policies. Review those policies if privacy matters, and avoid sending unnecessary identifying information in request parameters.

Never enter a recovery phrase, private key or wallet password into an RPC provider’s site or request. Standard RPC use does not require those secrets. Your wallet signs transactions locally or through its own secure signing process, then sends the signed transaction to the network. Be especially cautious of tools that claim you must reveal a secret to “activate” an endpoint.

A malicious or compromised endpoint could provide false read data, censor requests or interfere with broadcasting. For high-value activity, verify the network and transaction details through another trusted service. Check the destination, amount, token and fees in your wallet’s confirmation screen; do not rely only on a website’s display.

For an app, restrict access to provider credentials where possible, rotate exposed keys, and monitor usage. Keep a fallback only if you can verify it serves the same chain. A public RPC endpoint is infrastructure, not a security guarantee: use wallet protections, review every signature request, and confirm that you are interacting with the intended dApp and network.