Balance changes — balance

Subscribe to the balance channel to follow an address's balance. By default you receive the confirmed balance at each block; add pending: true to receive the pending (mempool) balance delta instead.

{ "action": "subscribe", "channel": "balance", "address": "0xa1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8a9b0" }
{ "action": "subscribe", "channel": "balance", "address": "0xa1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8a9b0", "pending": true }

balance — confirmed

Sent once per block in which the address was active.

{
  "type": "balance",
  "address": "0xa1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8a9b0",
  "confirmedWei": "12395678000000000000",
  "height": 19234567
}

Field	Type	Description
type	string	Always "balance".
address	string	The subscribed address.
confirmedWei	string	New confirmed balance in wei, as a decimal string (wei values exceed JSON's safe integer range) — the same field name the REST address-balance endpoint returns.
height	integer	Block height the balance corresponds to.

pending_balance — pending (pending: true)

Sent whenever the address's pending native-balance delta changes — a new pending transaction touches it, or one of its pending transactions is mined or expires.

{
  "type": "pending_balance",
  "address": "0xa1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8a9b0",
  "pendingWei": "-1000000000000000000"
}

Field	Type	Description
type	string	Always "pending_balance".
address	string	The subscribed address.
pendingWei	string	Signed pending delta in wei (negative if net-spending). "0" when there are no pending transactions.

Optional & native-value only

Pending events are an optional feature and may not be available on every network. They cover native value only — gas is excluded and token transfers are invisible until a transaction is mined. Subscribing where pending tracking is unavailable succeeds, but no pending events arrive.