March 28, 2025 — In a landmark development for blockchain interoperability, Cosmos developers have completed the first-ever Inter-Blockchain Communication (IBC) transaction directly between the Cosmos Hub and the Ethereum testnet. The milestone was announced on March 26 by Maghnus Mareneck, co-CEO of Cosmos, marking a significant step in the evolution of cross-chain connectivity.
“Hello world. The first ever Hub IBC transaction to Ethereum testnet! After many years of waiting, IBC is now connecting to every ecosystem,” said Mareneck in a celebratory post on X.
The transaction forms part of the upcoming Eureka upgrade, set to be introduced in IBC-go v10 later this year. It showcases the Cosmos network’s expanding vision of building a fully interoperable blockchain ecosystem.
Cosmos’ IBC protocol, first activated in March 2021 following the successful Stargate upgrade, enables independent blockchains to securely exchange assets and data. Since its inception, IBC has been integrated across various blockchains within the Cosmos ecosystem, including Terra, Osmosis, and Akash, fostering seamless communication between these networks.
While prior efforts have facilitated cross-chain interoperability between Cosmos and external chains through intermediaries, this recent test is the first direct IBC interaction between Cosmos Hub and Ethereum. Notably, Picasso Network enabled indirect IBC connections between Cosmos and Ethereum in April 2024, as well as with Solana. Similarly, Composable Finance has bridged Cosmos with both Polkadot and Kusama.
This milestone is another stride toward Cosmos’ long-term vision of making IBC the universal standard for blockchain communication, bridging the gap between isolated ecosystems and creating a more connected, efficient, and scalable decentralized web.
The success of this initial test opens the door to full-scale integration of Ethereum into the IBC ecosystem, potentially unlocking new levels of cross-chain utility, liquidity, and application development.
As the Eureka upgrade nears release, the Cosmos team continues to demonstrate its leadership in blockchain interoperability, pushing the boundaries of what cross-chain communication can achieve in the evolving Web3 landscape.
