Hedera Mainnet Completes v0.77 Upgrade with Pectra Features

100 percent of transactions on the Hedera network now run under the new Simple Fees structure.

Hedera v0.77 is live on Hedera mainnet, which it reached on Sep. 29, 2026, per Hedera’s release notes, adding Ethereum Pectra support and completing Simple Fees. NFA.

Upgrade Timeline

Hedera’s release notes confirm v0.77 reached mainnet on Sep. 29, 2026 after testnet on Sep. 15. Hedera Status shows the v0.77.2 mainnet upgrade began at 1:00 PM ET on Sep. 29 and finished at 1:35 PM ET. A follow-up upgrade to v0.77.5 completed on Oct. 3 at 10:20 PM ET. The rollout followed standard steps without reported interruptions.

Ethereum Pectra Support

Hedera’s release notes state that v0.77 delivers Ethereum Pectra support under HIP-1341 in the Smart Contract Service. The update includes a BLS12-381 precompile that matches EIP-2537. It also adds higher calldata gas costs from EIP-7623, access lists from EIP-2930, and contract creation code size validation from EIP-3860. A size limit on system contract calls is now active. HIP-1340 for EOA code delegation ships in a deactivated state and will arrive in a later release.

Simple Fees Migration

Hedera says v0.77 completes the HIP-1261 Simple Fees migration that began in v0.73. Every transaction now uses the new system. The legacy fee calculation method has been removed entirely. Fees now follow a uniform model that uses a base fee plus any extras, scheduled in system file 0.0.113. Hedera’s fee docs describe this approach as more predictable for users and developers.

Query Changes

Hedera says v0.77 removes the legacy AccountBalanceQuery from mainnet. Developers must switch to mirror node queries instead. Hedera’s blog from Oct. 1 notes that MirrorNodeAccountBalanceQuery is available in the JavaScript, Java, and Go SDKs. These queries carry no fee.

Developer Impact

For most smart contract work the Pectra changes bring direct compatibility with recent Ethereum improvements. Balance checks require the updated mirror node path. No other code changes are required for the fee or query shifts based on the available details. The network upgrade keeps Hedera aligned with Ethereum standards while maintaining its own fee and query structure.

Next Steps

Teams can review the release notes and status pages for exact timing. SDK updates are already published for the new balance query method. Further releases will handle the remaining deactivated items listed in v0.77.