Project Leap tests post-quantum signatures in live payment systems
1 DECEMBER 2025, BASEL
Project Leap completed its second phase in December 2025, testing post-quantum signatures in live payment systems. The BIS Innovation Hub ran the work with the Banque de France, the Bundesbank, Banca d'Italia, Nexi-Colt and Swift. By involving real institutions and real infrastructure, the project moved post-quantum cryptography out of the laboratory and into practical payment settings.
The headline finding is encouraging but qualified. Post-quantum signatures work in live payment systems, but they add processing time compared with current cryptography. That result points to a real-world cost, which helps institutions plan for the performance impact of migration rather than discover it late in their own rollouts.
Testing in live systems is what gives the finding its value. Laboratory tests cannot fully reveal how new cryptography behaves under real payment loads and integrations, so running the signatures through actual systems with real institutions surfaces practical issues like processing time. Those are exactly the issues institutions need to understand before committing to a full migration.
Why it matters. Project Leap gives the financial sector hard evidence that post-quantum signatures function in live payment systems, along with a clear caveat about added processing time. That combination lets institutions plan realistically, budgeting for performance effects instead of assuming a seamless swap. The involvement of major central banks and Swift signals that the sector is actively testing migration, not just discussing it.