Double Disinflation Rate

Summary

Reduce the inflation schedule by increasing the disinflation rate from the current -15% rate to -30%.

Technical Sponsor

Not required for this SGP.

The technical change is intentionally minimal and should be implemented through the normal Solana client development process. The relevant client teams should ensure the feature gate, conformance tests, and activation behavior are implemented consistently across validator clients.

Financial Sponsor

Not required for this SGP.

No separate funding request is proposed. The change is small in implementation scope and can be handled through existing protocol development processes.

Related SIMDs and SGPs

SIMD-0550 Double Disinflation Rate: The primary related SIMD. This SGP is intended to express validator and governance support for SIMD-0550 and its rollout requirements.

SIMD-0411 Prior Double Disinflation Proposal: An earlier version of SIMD-0550 that proposes the same changes.

SIMD-0228 Market-Based Emission Mechanism: Relevant historical context. SIMD-0228 proposed a more complex inflation mechanism and failed to reach quorum.

Motivation

While there is a significant appetite to reduce the nominal inflation rate of SOL, mechanism design has become a point of contention, ultimately leading to SIMD 228 failing to reach quorum. This SGP represents a simplification of the idea, delivering predictable inflation reduction by doubling the disinflation rate.

An SGP is the right instrument because this is first and foremost a governance question: should the network pursue a faster reduction in SOL inflation?

Proposal

This proposal asks validators and delegators to endorse doubling Solana's annual disinflation rate from 15% to 30%. After activation, SOL inflation should decline toward the 1.5% terminal rate twice as quickly as it does today.

This proposal preserves the current design of Solana's inflation schedule:

• the terminal inflation rate remains at 1.5%
• the schedule remains deterministic and predictable
• staking rewards continue to use the existing protocol reward mechanism
• commissions, MEV, transaction fees, and block rewards are unchanged

Dependencies

This SGP depends on SIMD-0550 being accepted and activated through the normal Solana feature-gate process.

Impact and Open Questions

Doubling disinflation accelerates the timeline of reaching the terminal emissions rate from a period of ~5.7 years to ~2.8 years. This would result in a reduction of approximately ~18.9 million SOL in emissions over the next 6 years, which is ~2.6% lower than the current disinflation schedule. With 41% of validators already opting for a 0% commission on emissions, this change would result in little realized reduction in revenue for many validators, with a soft taper so the remaining 59% do not experience any immediate significant shock to projected earnings. A more detailed breakdown can be found in the accompanying forum post.

• The realized impact on validator economics depends in part on future staking participation and commission trends, which may shift before activation.