---
title: Durable Nonces
description:
  How durable nonces work on Solana for offline signing and delayed transaction
  submission, including nonce lifecycle, detection, validation, and failure
  behavior.
url: /docs/core/transactions/durable-nonces
type: conceptual
prerequisites:
  - /docs/core/transactions
  - /docs/core/transactions/transaction-structure
related:
  - /docs/core/transactions/transaction-pipeline
  - /docs/core/programs/builtin-programs
---

<Callout type="info" title="Summary">
  Durable nonce transactions replace the recent blockhash with a stored nonce
  value, removing the 150 slot expiry window for a transaction. This enables
  offline signing and delayed submission.
</Callout>

<Callout type="warn">
  Durable nonces may be deprecated in a future release. See [SIMD
  discussion](https://github.com/solana-foundation/solana-improvement-documents/discussions/415)
  for details.
</Callout>

## Durable nonces

A durable nonce transaction replaces the recent blockhash with a stored nonce
value, removing the 150 slot expiry window. This enables offline signing and
delayed submission.

### How nonce transactions work

A nonce account is a System Program-owned account that stores a
_rs`State::Initialized`_ value containing three fields: an **authority** pubkey
(who can advance the nonce), a **durable nonce** value (a hash derived from a
recent blockhash), and **lamports per signature** (the fee rate when the nonce
was last advanced).

To use a durable nonce:

1. Create and initialize a nonce account using _rs`CreateAccount`_ +
   _rs`InitializeNonceAccount`_
2. Build the transaction with _rs`AdvanceNonceAccount`_ as the **first
   instruction** and the nonce value as the `recent_blockhash`
3. Sign the transaction (can be done offline, since the nonce does not expire)
4. Submit when ready

### Nonce detection

The runtime detects nonce transactions by checking whether the first instruction
(index
[`NONCED_TX_MARKER_IX_INDEX`](https://github.com/anza-xyz/agave/blob/v3.1.8/svm-transaction/src/svm_message.rs#L20)
= 0) is a call to the System Program with the _rs`AdvanceNonceAccount`_
instruction. The nonce account must be the first account of that instruction and
must be writable. See
[`get_durable_nonce`](https://github.com/anza-xyz/agave/blob/v3.1.8/svm-transaction/src/svm_message.rs#L89-L121).

### Nonce validation flow

When a transaction's `recent_blockhash` is not found in the `BlockhashQueue`,
the validator checks if it is a valid nonce transaction via
[`check_transaction_age`](https://github.com/anza-xyz/agave/blob/v3.1.8/runtime/src/bank/check_transactions.rs#L152-L180):

1. The nonce's stored `durable_nonce` must differ from the next durable nonce
   (derived from the current blockhash). This ensures the nonce has not already
   been used in this block
2. The nonce account must be loaded and must parse as _rs`State::Initialized`_
3. The stored `durable_nonce` must match the transaction's `recent_blockhash`

The nonce authority signing check is performed later
([`validate_transaction_nonce`](https://github.com/anza-xyz/agave/blob/v3.1.8/svm/src/transaction_processor.rs#L676-L729)).

If all checks pass, the nonce is advanced to the next durable nonce value before
execution begins. On execution failure, the advanced nonce and the fee-deducted
fee payer are still committed (preventing replay while collecting fees).

### Nonce failure behavior

If a nonce transaction **fails validation** (nonce already used, authority not
signed, account not found), the entire transaction is dropped. No fees
collected, no state changes.

If a nonce transaction **passes validation but execution fails** (an instruction
returns an error), the nonce is still advanced and fees are still collected.
This prevents the transaction from being replayed while ensuring the validator
is compensated.