transactionSubscribe

Subscribe to real-time transaction events with custom filters. Monitor specific accounts, exclude vote transactions, and receive instant notifications with configurable detail levels.

Endpoints

Enhanced WebSockets are available on mainnet and devnet:

• Mainnet wss://mainnet.helius-rpc.com/?api-key=<api-key>
• Devnet wss://devnet.helius-rpc.com/?api-key=<api-key>

WebSockets have a 10-minute inactivity timer; implementing health checks and sending pings every minute is heavily recommended to keep the WebSocket connection alive.

Authorizations

api-key · string · required

Your Helius API key. You can get one for free in the dashboard.

Body

params · array · required

Hide TransactionSubscribeFilter

vote · boolean

Include or exclude vote-related transactions.

failed · boolean

Include or exclude transactions that failed.

signature · string

Filter updates to a specific transaction by its signature.

accountInclude · string[]

List of accounts to receive transaction updates for. A transaction must include at least one of these accounts. Supports up to 50,000 addresses.

accountExclude · string[]

List of accounts to exclude from transaction updates. Supports up to 50,000 addresses.

accountRequired · string[]

List of accounts that must all be included in a transaction for it to match. Supports up to 50,000 addresses.

tokenAccounts · string

Opt in to associated token account (ATA) expansion so an accountInclude wallet also matches transactions where it owns an SPL token balance — for example, incoming token transfers that touch the wallet’s token account rather than its pubkey. Accepts:

• "balanceChanged" — match when the wallet owns a token balance whose amount changed (or whose token account was closed) in the transaction.
• "all" — match any transaction referencing a token balance the wallet owns, even if unchanged. Higher volume.
• "none" — same as omitting the field (no expansion). This is the default.

An invalid value returns JSON-RPC error -32602: Invalid tokenAccounts value '<x>', expected one of: none, balanceChanged, all.

Show TransactionSubscribeOptions

commitment · string

Commitment level for fetching data. Can be processed, confirmed, or finalized.

encoding · string

Encoding format for the returned data. Can be base58, base64, or jsonParsed.

transactionDetails · string

Level of detail for the returned transaction data. Can be full, signatures, accounts, or none.

showRewards · boolean

Whether to include reward data in the updates.

maxSupportedTransactionVersion · integer

The highest transaction version to receive updates for. Set to 0 to get both legacy and versioned transactions.

Required when transactionDetails is set to "accounts" or "full".

Response

result · integer

Subscription id (needed to unsubscribe)

Request

{
  "jsonrpc": "2.0",
  "id": 420,
  "method": "transactionSubscribe",
  "params": [
    {
      "accountInclude": ["675kPX9MHTjS2zt1qfr1NYHuzeLXfQM9H24wFSUt1Mp8"]
    },
    {
      "commitment": "processed",
      "encoding": "jsonParsed",
      "transactionDetails": "full",
      "showRewards": true,
      "maxSupportedTransactionVersion": 0
    }
  ]
}

Response

{
  "jsonrpc": "2.0",
  "result": 4743323479349712,
  "id": 420
}

Managing Subscriptions

Subscription IDs

When transactionSubscribe succeeds, the server returns a subscription ID in the result field. This is the same number that appears in params.subscription on every notification from that subscription:

Subscribe Response

{
  "jsonrpc": "2.0",
  "result": 4743323479349712,
  "id": 420
}

Store the subscription ID from the response. You need it to unsubscribe.

Unsubscribing

To stop receiving notifications, call transactionUnsubscribe with the subscription ID. Each transactionSubscribe call on the same connection creates a separate subscription with its own ID, so make sure to unsubscribe before resubscribing to avoid receiving duplicate notifications.

Request

{
  "jsonrpc": "2.0",
  "id": 421,
  "method": "transactionUnsubscribe",
  "params": [4743323479349712]
}

A few in-flight messages may still arrive briefly after calling transactionUnsubscribe. This is expected behavior.