SUI (SUI) Tokenomics

The SUI token is the native asset of the Sui Layer-1 blockchain, which operates on a Delegated Proof-of-Stake (DPoS) consensus mechanism. The tokenomics are designed to align incentives across users, validators, and the Sui Foundation, supporting network security, transaction processing, and long-term ecosystem growth. The maximum supply of SUI is capped at 10 billion tokens.

Issuance Mechanism

The SUI token supply is fixed at 10 billion tokens. The issuance mechanism is primarily driven by the release of tokens according to a predetermined vesting schedule and through staking rewards.

• Fixed Supply: The long-run circulating supply is capped at 10 billion SUI.
• Initial Circulation: At the Mainnet launch on May 3, 2023, approximately 5% of the total tokens were in circulation.
• Reward Subsidies: An initial subsidy of 1 billion SUI (10% of the maximum supply) was allocated to reward validators during the first year of the network's life. This subsidy is drawn from the total supply and distributed as part of the staking rewards.
• Inflation: The network's annualized inflation rate has been decreasing, starting at 4.9% in Q3 2023 and declining to near zero (0.0%) by Q3 2024, indicating a maturing economic model with reduced token supply growth over time.

Allocation Mechanism

The total supply of 10 billion SUI tokens was allocated across several categories to support the network's launch and ongoing development.

Note: Third-party sources report slightly different allocations, such as 36.53% for the Community Reserve and 21.14% for Early Contributors, along with separate allocations for Series A and Series B investors.

Usage and Incentive Mechanism

The SUI token serves multiple utility functions within the network, primarily focused on security, transaction processing, and liquidity provision.

1. Network Security and Staking Incentives (DPoS)

Sui uses a Delegated Proof-of-Stake (DPoS) mechanism where SUI holders can stake their tokens to validators to secure the network and earn rewards.

• Validator Staking: To operate a validator, a tokenholder must stake at least 30 million SUI. A validator's chance of validating a transaction is proportional to its percentage of the total staked SUI supply.
• Delegator Staking: Tokenholders can delegate any amount of SUI to an existing validator. Delegators share in the rewards earned by the validator, minus the validator's commission rate.
• Reward Sources: Validator and delegator rewards are sourced from:
  • Computation Fees: Distributed to the validators that processed the transaction.
  • Storage Fund Rewards: Distributed to validators to compensate for storing data.
  • Reward Subsidies: Drawn from the 1 billion SUI subsidy during the network's first year.
• Storage Fund: A unique feature where storage fees from transactions are deposited into a Storage Fund. This fund is used to reward future validators for storing data created by today's transactions, ensuring long-term data availability and incentivizing new validators. The tokens held in the Storage Fund also accrue rewards from their proportionate share of the total staked supply.

2. Transaction Fees (Gas)

SUI is used to pay for all transaction fees on the network.

• Gas Pricing Mechanism: The price of gas fees is set at the start of each epoch (approximately 24 hours) to provide users with low and predictable transaction costs.
• Fee Components: Transaction fees charge the initiator for both computation and storage.
  • Computational charges are distributed to the validators.
  • Storage fees are deposited into the Storage Fund.

3. Liquidity and Ecosystem Use

SUI is also used for liquidity provision and ecosystem development:

• DeepBook Pools: Users incur a one-time fee of 100 SUI to create trading pools on DeepBook, Sui's central limit order book.
• Governance (Future): While no active governance process exists as of early 2024, SUI is intended to be used as voting power for future protocol upgrades and governance changes. Staked SUI will grant token holders the ability to participate in this process.

Locking Mechanism and Unlocking Time

SUI tokens are subject to vesting schedules that govern when allocated tokens become liquid.

Locking Mechanism

• Staking Lock: When SUI tokens are staked to a validator, they are locked for the entire epoch (approximately 24 hours). Users can request to withdraw their stake at any time, but the withdrawal only becomes active at the start of the next epoch.
• Vesting Schedules: Tokens allocated to Early Contributors, Investors, and the Mysten Labs Treasury are subject to multi-year vesting schedules to ensure a gradual release of supply.

Unlocking Schedule and Timeline

The vesting and distribution schedule for SUI tokens is designed to extend beyond 2030. The release schedule is phased to maintain network stability and prevent market oversaturation.

• Public Sale Tokens: Tokens purchased in the KuCoin Spotlight sale were distributed over 12 months, with one-third unlocked at Mainnet launch and one-thirteenth unlocked monthly thereafter. Tokens from the "Recognition Sale" for ecosystem contributors were fully unlocked upon Mainnet launch.
• Significant Unlocks: The vesting schedule includes major unlock events for key stakeholders:
  • Q2 2024: A significant unlock event was projected, with 1.4 billion SUI unlocking for private investors, representing 53.4% of the circulating supply at that time.
  • Q2 2025: Projected unlocks include 97.3 million SUI for Private Investors, 81.7 million SUI for the Ecosystem, 77.4 million SUI for Staking Rewards, and 48.0 million SUI for the Team.
  • Q3 2025: Projected unlocks include 57.9 million SUI for Private Investors, 37.8 million SUI for the Ecosystem, 36.3 million SUI for the Team, and 36.1 million SUI for Staking Rewards.

The gradual release of tokens, particularly those designated for the Ecosystem and Staking Rewards, indicates a long-term strategy focused on platform growth and incentivizing network participation. However, the exact details of the vesting schedules extending beyond 2030 have not been fully released.