Ethereum co-founder Vitalik Buterin has voiced strong support for the enhanced privacy steps taken by Signal, a widely used encrypted messaging app, as the platform works toward letting users register without a phone number.
Buterin champions privacy and digital autonomy
Vitalik Buterin, a prominent advocate for privacy within the crypto ecosystem, has consistently backed initiatives focused on protecting both user data and metadata. In line with his priorities for Ethereum, Buterin argued in an April 2025 essay that whoever controls information wields significant power, stressing the importance of resisting concentrated data collection, especially in the digital sphere where these activities are most viable.
In November 2025, Buterin made notable donations of 128 ETH each to both the Signal Foundation and SimpleX Chat, organizations aiming to allow users to create accounts without having to submit personal identifiers. He specifically commended both platforms for their commitment to enhancing account privacy and strengthening protections for user metadata.
Buterin highlighted that Sybil and denial-of-service resistance are complex without relying on traditional identifiers like phone numbers, and praised ongoing efforts to find privacy-preserving alternatives.
Signal is managed by the Signal Foundation, a nonprofit organization that develops open-source privacy technology. The foundation’s efforts have received global attention from privacy advocates and the broader crypto community.
Mini dictionary: Sybil resistance, a mechanism used in decentralized networks to prevent one entity from creating multiple fake identities and disrupting the system’s operations.
Signal tests phone-number-free accounts
Currently, Signal requires a phone number for account registration, a policy that privacy proponents like Buterin have criticized as a possible vulnerability. Recent updates reported by AboutSignal, an independent project tracking the app’s development, indicate that Signal is implementing back-end support to permit new accounts without requiring a phone number.
Code commits identified in Signal’s server repository reveal that new phone-free accounts will remain separate from existing, phone-linked accounts. This separation means users cannot remove a number from an older account or add one to a phone-free account; instead, the option is available only for new sign-ups.
Signal CTO Ehren Kret addressed the technical and security challenges in March, noting that preventing mass account creation by bad actors was a primary concern. Kret explained that the team is considering ways to attach some form of cost to phone-free sign-ups, which may or may not involve monetary payment. He stated that Signal aims to launch a version of this feature later in the year.
“We gotta figure out some way to induce a cost for signing up without a phone number,” Kret explained, adding that implementation might not necessarily require a financial fee.
Aligning Ethereum’s privacy ambitions
Vitalik Buterin has also contributed to efforts to strengthen privacy on Ethereum’s mainnet, with an emphasis on enabling private, uncensorable transactions and unattached on-chain activity. These updates aim to prevent external parties from linking wallet addresses and transaction histories to individual users, though these features remain in development and are not yet live.
Buterin sees the push for privacy on Ethereum and the steps taken by Signal as part of the same struggle: reducing the reliance on identifiable information in digital infrastructure. While Signal’s move would cut the use of phone numbers as identifiers, Ethereum’s initiatives intend to eliminate similar linking mechanisms from blockchain activity.
