eth_newFilter

Contract activity on BNB Smart Chain surfaces as event logs, and eth_newFilter is how you register interest in a specific slice of them. Chain ID 56 uses BNB as its gas token. Send the method to https://bsc.therpc.io/YOUR_API_KEY with an address and topic criteria, and it creates a server-side log filter that returns a hex filter ID. From then on you call eth_getFilterChanges with that ID to pull, incrementally, only the matching logs mined since your last poll. There is no need to restate the address-and-topics object on every request. The pattern pairs naturally with the chain's ~3-second PoSA block cadence for steady, low-overhead event ingestion.

Use cases

Poll for fresh BEP-20 Transfer events on a roughly per-block (~3-second) rhythm without re-specifying the full address-and-topics filter each time.
Watch a PancakeSwap pair contract for Swap events from a long-running indexer process, letting the server track your read position.

Parameters

#	Name	Type	Required	Description
1	`filter`	object	Yes	Filter object. Fields: `fromBlock` (string), `toBlock` (string), `address` (string \| string[]), `topics` ((string \| string[] \| null)[]).

Response

Type	Description
string	Hex filter ID. Pass this to eth_getFilterChanges, eth_getFilterLogs, or eth_uninstallFilter.

Example request

1curl https://bsc.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H "Content-Type: application/json" \
4  -d '{
5    "jsonrpc": "2.0",
6    "method": "eth_newFilter",
7    "params": [{}],
8    "id": 1
9  }'

Try it live in the BNB Smart Chain playground.

Errors & troubleshooting

Code	Message	Cause
`-32000`	`filter not found`	Provider rejected filter creation, or filter limit per connection was reached.
`-32602`	`invalid argument`	Malformed filter object or invalid topic format.

Common pitfalls

After roughly five minutes of inactivity the node garbage-collects the filter, so wire up recreation logic for when eth_getFilterChanges answers with filter not found.
Filter state lives on the server tied to your connection and vanishes on reconnect; always assume you may need to re-register the filter from scratch.
For genuinely real-time delivery, an eth_subscribe logs subscription over WebSocket beats repeatedly polling this filter.

Supported networks

Mainnet — Chain ID: 56
Testnet — Chain ID: 97