Quantum computing is no longer science fiction it’s a real security and policy challenge that many sectors, mainly Banking, must start planning for today. The main concern is that future quantum computers could break the encryption methods (RSA, Diffie-Hellman, ECC) that protect the core of banking: secure transactions, customer identity, payment systems, and even the software you rely on every day.

The risks in one page

  • Breakable building blocks – Asymmetric schemes we rely on (RSA/DH/ECC) rest on “hard math” like factoring and discrete logs. Quantum algorithms – most notably Shor’s – collapse that hardness, making today’s protections tomorrow’s liabilities. 
  • Harvest-Now-Decrypt-Later (HNDL) – Adversaries can steal encrypted data now and decrypt it later once quantum capabilities mature. If your data has a long shelf life (financial records, PII, legal archives), the risk is immediate, not hypothetical. 
  • Digital signatures at stake – It’s not just confidentiality. Signature forgery becomes feasible, undermining transaction integrity and identity proofs. For finance, that’s existential. 
  • Timeline uncertainty – Estimates vary, but many analysts suggest that strong quantum capabilities may appear within the next decade. The uncertainty itself reinforces the need for awareness and preparation.

Implications for the Banking System

  • Systemic risk – Banking relies heavily on encryption for secure communication, payments, and data storage. A breakthrough in quantum computing could compromise these foundations.
  • Regulatory expectations –  Supervisory authorities expect financial institutions to recognize quantum risk, assess exposure, and prepare transition strategies toward quantum-resistant solutions.
  • Post-Quantum Cryptography (PQC) – International standardization efforts, led by NIST, are advancing algorithms designed to withstand quantum attacks. These will gradually replace current cryptographic schemes across systems and services.
  • Critical areas of focus:
    • Long-lived sensitive data, which is already at risk due to “Harvest Now, Decrypt Later.”
    • Signature-based processes such as identity verification, code signing, and transaction approvals.
    • Dependency on vendors and third parties, where readiness may vary across the financial ecosystem.

The Strategic Response

The banking sector is expected to treat quantum risk as a multi-year transition in cryptographic governance. Key elements include:

  • Cryptographic inventory – Mapping where RSA, ECC, and other vulnerable schemes are used in protocols, products, vendor systems, and transaction processes.
  • Prioritization of long-lived data – Identifying and protecting sensitive information that must remain secure for many years.
  • Transition to post-quantum algorithms – Monitoring and adopting standards from NIST and related bodies to ensure resilience against quantum attacks.
  • Vendor and ecosystem coordination – Ensuring that third parties, payment networks, and technology providers align with post-quantum migration plans.
  • Supervisory alignment – Maintaining awareness at the executive level, conducting risk assessments, and aligning with regulatory guidance to ensure readiness across the sector.

Key message

Quantum computing introduces clear and measurable risks to the cybersecurity foundations of many organizations, but especially the banking sector. The ability to break today’s cryptographic standards directly impacts the confidentiality of customer data, the integrity of financial transactions, and the authenticity of digital identities. From a cybersecurity perspective, the threat is twofold: attackers may already be harvesting encrypted information for future decryption, and quantum capabilities could enable large-scale forgery of digital signatures.

While the exact timeline for quantum breakthroughs remains uncertain, the potential consequences for financial security and trust are significant. The sector is therefore expected to strengthen its cybersecurity posture by identifying where vulnerable cryptography is used, protecting long-lived sensitive data, and planning for a gradual transition to post-quantum standards.