Pre-Confirmations

What is a Pre-Confirmation?

A pre-confirmation is an intermediate transaction status that occurs after a transaction has been submitted and accepted by the blockchain, but before it is fully processed and included in a new block.

At this stage, the transaction is pre-executed and assigned one of two possible statuses:

• PreconfirmationSuccessStatus: The transaction is expected to be successfully included in a future block.

• PreconfirmationFailureStatus: The transaction will not be included in any future block.

Why are Pre-Confirmations important?

Pre-confirmations allow applications to react earlier by providing immediate feedback about a transaction's expected outcome without waiting for full block finalization.

Additionally, pre-confirmations expose processed outputs (such as OutputChange and OutputVariable) that can be immediately reused in new transactions.

Available Outputs for Pre-Confirmations

When a transaction reaches the pre-confirmation stage, certain resolvedOutputs become available:

• OutputChange: Represents the change UTXO generated from unspent inputs, grouped by assetId (one per asset).

• OutputVariable: Similar to OutputCoin, but only created if the transaction succeeds.

These outputs can be:

• Extracted directly from the pre-confirmation response.
• Used immediately to fund new transactions, without waiting for block confirmation.

This significantly improves the ability to build transaction sequences or reactive transaction flows.

This is the ResolvedOutput interface structure:

<<< @/../../../packages/account/src/providers/transaction-summary/types.ts#resolved-output-type{ts:line-numbers}

Example Workflow

Suppose you send a transaction that will send funds to another wallet.

As soon as you receive a PreconfirmationSuccessStatus, you can:

• Use the OutputChange in a new transaction.
• Submit the next transaction without waiting for block finalization.

This reduces wait times and accelerates transaction chaining.

Code Examples

Using Pre-Confirmations when Submitting a Transfer

The following example sends a transfer, waits for the pre-confirmation success, and then submits another transfer using the resolved outputs from the first:

<<< @./snippets/pre-confirmation/send-transaction.ts#pre-confirmation-send-transaction-1{ts:line-numbers}

Using Pre-Confirmations with a Contract Call

This example performs a contract call, waits for pre-confirmation success, and then uses the resolved output to execute another contract call:

<<< @./snippets/pre-confirmation/contract-call.ts#pre-confirmation-contract-call-1{ts:line-numbers}