Aptos has activated its Encrypted Mempool on mainnet, giving users an optional way to conceal transaction instructions before their ordering is finalized. According to the official Aptos announcement, AIP-144 encrypts transaction payloads before submission so validators can order them without seeing the function being called or its arguments, reducing the information available for front-running and sandwich strategies.
The feature went live on October 12 and operates directly through the Aptos validator set rather than relying on a separate builder, hardware enclave or external decryption committee. Encrypted transactions use the same validator trust boundary already securing Aptos consensus, with decryption requiring the stake-weighted threshold used by the network rather than an additional group of trusted parties.
Encryption Hides Intent Until Ordering Is Final
A compatible client retrieves an encryption key jointly generated by validators for the current epoch and encrypts the transaction payload locally before submission. The transaction enters the mempool encrypted and remains unreadable to the block leader while its position in the block is being determined. Once consensus finalizes the block, validators reconstruct the required decryption material and execute the revealed transaction.
The privacy boundary is deliberately limited. The first implementation hides the Move function and its arguments, while the sender account and gas-fee fields remain visible, and the complete transaction becomes auditable after decryption and execution. Encrypted Mempool therefore provides temporary protection for pending transaction intent rather than permanent transaction anonymity.
That makes it distinct from Aptos’ earlier Confidential APT implementation. Confidential APT protects balances and transfer amounts after settlement, whereas Encrypted Mempool protects transaction instructions before execution. The two mechanisms address different information leaks and remain optional rather than making Aptos private by default.
The cryptographic design uses batched threshold encryption so validators do not need to run a separate decryption protocol for every encrypted transaction. Aptos says the system can decrypt an entire block with constant-size communication per validator regardless of the number of encrypted transactions in that batch. Tests against a 50-node AptosBFT setup showed roughly 20 milliseconds of additional block latency, according to the project’s mainnet announcement.
Petra Opens Access While Decibel Prepares Integration
Petra is the first wallet to expose Encrypted Mempool directly in its transaction-signing flow. Users can opt into encryption when signing, while developers can use Aptos TypeScript SDK version 7.0.0 or later to retrieve the epoch key and construct encrypted submissions. Existing Move smart contracts do not need to be rewritten to receive transactions submitted through the encrypted path.
Aptos has also identified Decibel as an intended production use case, saying the perpetual futures venue will use encrypted transactions to conceal orders before execution. Decibel has already processed more than 31 million trades and $7.7 billion in cumulative volume, making trading a concrete environment where pre-execution information leakage can matter. Aptos has announced Decibel’s intended use of the system, but that statement should not yet be treated as confirmation that all Decibel orders are using Encrypted Mempool.
Using encryption also changes transaction economics slightly. Aptos documentation lists a minimum gas unit price of 200 octas for encrypted pending transactions, compared with a 100-octa floor for ordinary transactions. That requirement is a higher minimum gas price rather than a separate fixed privacy fee, and actual costs still depend on gas consumption and network conditions.
The rollout arrives while Aptos is already processing high transaction volumes at low average fees. Recent network data showed hundreds of millions of monthly transactions and sub-cent average execution costs. Those throughput figures establish the scale of the underlying network, but they do not demonstrate adoption of encrypted transactions themselves.
For traders and applications, the main change is therefore narrower than general blockchain privacy. Aptos now provides a protocol-native mechanism for hiding transaction intent until block ordering is fixed, reducing the information available for specific forms of harmful MEV without concealing the transaction permanently. Future usage data will determine how broadly wallets, trading applications and automated systems adopt the optional encrypted path.