Cardano Activates van Rossem Hard Fork to Cut Smart-Contract Costs

Cardano's van Rossem release is an intra-era upgrade, meaning the blockchain remains in the Conway era rather than splitting into a rival chain. It expands Plutus smart-contract capabilities and strengthens ledger and node security, while preparing the network for Ouroboros Leios, a throughput-focused scaling overhaul targeted for late 2026. The change is also Cardano's first hard fork approved entirely through on-chain governance, with delegated representatives, stake-pool operators and the Constitutional Committee all participating in authorization.

The mainnet activated van Rossem at 21:44:51 UTC on July 18, 2026, at the boundary of epoch 644, moving Cardano from Protocol Version 10 to 11.0 without reported downtime. The release adds Plutus primitives and cost-model improvements designed to make smart-contract execution faster and cheaper, while keeping transaction structure and the Conway ledger era intact. The governance action was ratified on July 13, following earlier Preview and PreProd testnet deployments; Intersect MBO and the Cardano Foundation had urged infrastructure operators to update compatible software before activation.