Solana (SOL) developers have rolled out a sweeping upgrade to their privacy tooling under the banner of “Confidential Balances,” introducing a new suite of cryptographic extensions that discreetly shield token movements while preserving regulatory compliance.
The features, which build upon the earlier “Confidential Transfers” functionality launched in Solana’s Token2022 program, now offer token issuers a broader toolbox for hiding sensitive transaction details, including details about amounts transferred, minted, burned, or charged as fees, using homomorphic encryption and zero-knowledge proofs (ZKPs).
Unlike traditional privacy-focused technologies that often conflict with financial transparency mandates, Solana’s approach favors the term “confidentiality,” positioning the tools as compliant enhancements rather than mechanisms for anonymity.
Confidential Balances
Under the Confidential Balances umbrella, issuers and users gain access to multiple extensions: confidential transfers, confidential transfer fees, and confidential mint and burn.
These tools allow transactions to be validated on-chain without publicly exposing sensitive data. Rust-based backends are already powering early implementations of these features, allowing Wallets-as-a-Service providers to handle encryption and proof generation off-chain.
While mainstream wallets have yet to offer full native support, developers expect that to change with the upcoming release of JavaScript-based ZK-proof libraries later this year.
Once integrated, these client-side libraries could enable browser and mobile wallets to generate and verify cryptographic proofs locally, eliminating the need for server-side support and making confidential transactions more accessible to users.
Balancing user privacy with institutional compliance
The rollout also includes optional compliance features such as “auditor keys,” which allow institutions or regulators to review transactions without revealing amounts to the general public.
When configured by a token issuer, an auditor key can decrypt or access cryptographic proofs related to confidential token activity, such as the exact amounts transferred, minted, or burned, without exposing this data to the broader network or public.
These keys do not interfere with the confidentiality of user balances or transactions on-chain but instead act as a parallel mechanism for oversight. Importantly, their use is entirely optional and customizable: projects can assign auditor keys to regulated financial institutions, internal compliance teams, or third-party auditors, depending on jurisdictional needs.
This design allows for institutional-grade privacy with auditability, making it possible to meet anti-money laundering (AML), counter-terrorist financing (CTF), or tax reporting obligations while maintaining a high degree of user confidentiality.
