Rongchai Wang
Jan 16, 2026 15:38
Sei’s SIP-3 improve deprecates CosmWasm to grow to be EVM-only by mid-2026. USDC.n holders should migrate belongings by March or threat shedding entry.
Sei Community is gutting its Cosmos roots to chase 200,000 transactions per second. The SIP-3 improve, accepted by governance final Might, will rework Sei into an EVM-only chain by mid-2026—and customers holding legacy IBC belongings have to act now or lose entry to their funds.
The primary domino falls this month. Model 6.3, deploying to Pacific testnet in January, permits full staking performance by way of EVM interfaces. March brings v6.4, which provides the kill change for inbound IBC transfers. As soon as that governance proposal passes, Cosmos-native tokens like ATOM and USDC.n can not enter the community.
The Weight Discount Technique
Sei Labs frames this as automotive engineering: to make one thing quick, you both add energy or lower weight. SIP-3 does the latter, stripping “lots of of hundreds of strains of code” from the protocol. The Giga improve coming afterward presumably handles the ability facet of that equation.
What’s getting eliminated? CosmWasm good contract help. Native Cosmos transaction dealing with. The chain’s built-in oracle resolution—changed by Chainlink, API3, and Pyth. IBC interoperability, each inbound and outbound transfers, will probably be disabled by way of separate governance votes.
By the point this wraps up, solely EVM addresses will have the ability to provoke transactions on Sei. Full cease.
USDC.n Holders Face Deadline Strain
Here is the pressing half: anybody holding USDC through Noble (USDC.n) must migrate to native USDC earlier than late March 2026. Sei Labs is not being refined about this—they have been warning customers since early January to swap or migrate instantly.
The excellence issues. Native USDC, which went reside on Sei with Circle’s CCTP v2, provides institutional-grade infrastructure and regulatory compliance. USDC.n, the bridged Cosmos model, turns into nugatory baggage as soon as IBC transfers shut down.
Sei Labs factors customers towards Skip:Go as one migration choice, although they’re cautious to notice this is not an endorsement. Customers in DeFi protocols with USDC.n publicity ought to “wind down any reliance on these belongings,” in response to the announcement.
What Adjustments for Builders
Infrastructure suppliers face the most important elevate. Indexers and custodians have to replace their methods to trace staked steadiness modifications by way of EVM APIs. Any software constructed on CosmWasm wants an entire rewrite or abandonment.
The upside for builders who stick round: a cleaner, extra aggressive place inside the broader EVM ecosystem. Fewer edge circumstances. One execution surroundings as a substitute of two. Whether or not that tradeoff appeals is dependent upon how a lot Cosmos-specific performance a challenge truly used.
Timeline and Buying and selling Implications
The complete transition completes by mid-2026, however the crucial dates hit sooner. Q1 2026 brings the IBC inbound shutdown. Further releases will disable outbound transfers and sundown the native oracle.
For merchants, watch the governance proposals. Every vote that passes removes one other Cosmos functionality and probably triggers migration flows. The USDC market, at present at $75.72 billion in market cap, will not discover Sei’s transition—however Sei’s inside liquidity dynamics might shift as legacy belongings exit.
Sei is betting that changing into a pure EVM chain at 200K TPS beats being a hybrid at decrease speeds. Customers have till March to resolve in the event that they’re coming alongside for the trip.
Picture supply: Shutterstock






