XRP Ledger Draft Adds NIST Post-Quantum Signatures, Keeps Fees Unchanged

The XRP Ledger Foundation has published a draft specification that would add NIST-standardized post-quantum signatures to the ledger while leaving its fee schedule untouched. The proposal, opened on July 8, 2025 and last updated May 20, 2026, would introduce ML-DSA-44 as a signing option covering account transactions as well as validator and publisher signatures. Activation requires a validator vote, and no activation date exists yet.

The Foundation's Nov. 4 roadmap schedules research on account migration for the first half of 2027, followed by development, review and audit work in late 2027 or 2028. The document estimates 640 development hours and a budget of $215,000 to $255,000, with development hours excluded from that amount.

What standard does the draft adopt?

ML-DSA-44 is a lattice-based signature scheme that the National Institute of Standards and Technology standardized in FIPS 204. The draft would make it available across XRP Ledger signing: user account transactions, and the signatures validators and publishers use to secure consensus operations.

The scheme carries a substantial storage penalty. An ML-DSA-44 public key runs 1,312 bytes and a signature can reach 2,420 bytes. The Foundation estimates 5,331 bytes for a protected use, compared with 1,704 bytes for an ordinary payment — roughly three times the on-chain footprint.

How would accounts migrate?

Existing accounts would not switch automatically. A user seeking post-quantum protection would need to replace the account's regular signing key with one derived from Dilithium, or transfer funds to a newly derived account. The migration study planned for the first half of 2027 is the Foundation's next step toward answering how that process works at scale.

The proposal deliberately avoids touching economics. It leaves fee and reserve levels to network operators through the ledger's standard fee-voting mechanisms, so the larger signature sizes do not translate into a hardcoded cost change.

Who pays for the build?

The $215,000-to-$255,000 estimate includes:

• 400 hours of Ripple review
• an external audit
• a reference implementation
• work on Ledger hardware wallets and community wallets

The 640 development hours sit outside the dollar budget as a separate line. The split reflects the project's structure: Ripple reviews the code, while the Foundation coordinates specification, implementation and third-party assurance.

The Foundation was explicit about the proposal's status. "Nothing here is promised. An amendment activates only if the validators vote it in," the organization wrote in the roadmap. Until that vote occurs, the draft remains a specification rather than an active network feature.

How does this relate to Ripple's own timeline?

Ripple separately set a 2028 target for a full post-quantum transition in April 2026. That corporate target is distinct from the Foundation's research schedule, which only commits to a migration study in the first half of 2027 before development begins. The two schedules could converge if development and audit work completes in 2028, but the Foundation's roadmap does not bind itself to Ripple's deadline.

For ledger operators, the near-term operational question is the migration study's findings in the first half of 2027, which will determine whether key replacement or fund transfer emerges as the dominant path for the roughly threefold increase in per-use data that quantum-resistant accounts will demand.