Exchanges and custodians that list SEI have roughly five and a half weeks to complete a technical migration before Sei Network permanently shuts down its Cosmos-based transaction layer. The hard deadline of June 15, 2026, was set under Sei Improvement Proposal 03 (SIP-03), a governance decision that converts Sei into an EVM-only blockchain. Platforms that miss the cutoff will be unable to process withdrawals to unassociated native Sei addresses, specifically those sei1... addresses whose pairing with an EVM-format 0x address has not been established before the deadline, leaving users unable to access funds held in those accounts.

SIP-03 ends Sei's dual-architecture design, which previously let users interact with the network through either its original Cosmos layer or its Ethereum Virtual Machine (EVM) layer. The Cosmos side handled things like cross-chain transfers via IBC (a messaging protocol connecting Cosmos-based blockchains) and smart contracts written in CosmWasm. All of that is now being retired. Sei Labs co-founder Jay Jog has emphasized that integration teams need to reframe how they think about the change: "Sei EVM is not a separate chain. It's the same chain with a second way to interact with it." The practical implication is that exchanges treating Sei native and Sei EVM as two distinct chains in their internal systems will need to consolidate those records before the deadline.

The governance vote to enforce SIP-03 passed on May 1, 2026, immediately blocking any new CosmWasm smart contract deployments on the network. That vote was the latest step in a deprecation process that began with a governance discussion in Q2 2025. Key milestones included disabling inbound IBC transfers in February, removing Sei's native oracle in March, and taking the Cosmos transaction layer offline in early April. Coinbase completed its own migration during the April 6 to 8 window, temporarily suspending SEI deposits and withdrawals before automatically crediting customers with EVM-compatible token balances. Users on Coinbase did not need to take any manual steps.

The technical crux of the migration involves address formats. Every Cosmos-style address beginning with "sei1..." corresponds to exactly one Ethereum-format address beginning with "0x...". These pairings are fixed and derived from the same underlying public key; they cannot be changed or reassigned. Exchanges that created customer accounts using native Sei addresses need to establish those address associations before June 15. After that date, Sei's Cosmos interface will go dark entirely, and any funds sitting in unassociated native addresses will become inaccessible. Migration paths for integration teams are documented in Sei's official technical reference at docs.sei.io/learn/sip-03-migration.

For users outside the United States, the situation carries added complexity. According to the 2026 Global Crypto Adoption Index, India ranks first, Nigeria second, and Pakistan eighth globally for retail crypto adoption. Any platform in those regions that lists SEI and relies on Cosmos-style withdrawals faces a real risk of service disruption after June 15. The situation is made more difficult by Leap Wallet's announcement that it will shut down permanently on May 28, eighteen days before the Sei deadline. Leap was widely used across South Asia's Cosmos user base. People who managed their Sei holdings through Leap now need to find a replacement wallet and complete the chain migration within the same narrow window. Additionally, Sei's disabling of IBC removes a cross-chain routing layer that DeFi users in Africa and South Asia have relied on to move assets between Cosmos-connected networks like Osmosis and the Cosmos Hub. EVM-compatible bridges such as Wormhole, LayerZero, and Circle's CCTP can partially fill that gap, but they require users to adopt different tooling.

Sei's move is part of a broader pattern in the Cosmos ecosystem. Noble, a stablecoin-focused chain, also announced a migration to an EVM L1 in early 2026. The EVM ecosystem now accounts for more than 90% of all decentralised application development activity, a figure Sei Labs has cited as the primary rationale for consolidating around a single execution model. Not all community members welcome the direction. One dissenting voice in the GitHub governance discussion argued that "moving from SEI's high-performance, Cosmos-native L1 to an Ethereum execution model is not progress. It's regression." That view represents a segment of the community that sees the migration as abandoning a technical identity rather than upgrading it.

SEI is currently trading around $0.061, giving the token a market capitalisation of approximately $423 million and placing it at rank 96, both according to CoinMarketCap. That price sits approximately 94.7% below its all-time high of $1.14, according to CoinGecko. Total value locked on Sei stands at about $64 million according to DefiLlama, down sharply from a peak above $560 million in mid-2025. The network reports more than 5 billion total transactions processed and over 90 million wallets created.

Looking ahead, the June 15 deadline is not the end of the story but a gateway to a larger infrastructure overhaul. Sei's roadmap points toward the Sei Giga upgrade, which targets 200,000 transactions per second and sub-400-millisecond finality through a rebuilt EVM execution client. The project has also confirmed a partnership with Xiaomi to preinstall Sei Wallet on smartphones sold outside China and the United States, with Southeast Asia identified as a key growth market within that broad global deployment. The arrangement is a commercial bet that makes a clean, unified address system more important than ever. Technical support for migration questions is available through Sei's Telegram tech chat and Discord.