Preparing for post-quantum encryption: what organisations should do now

Quantum computers capable of breaking widely used public-key cryptography may still be years away, but migration (to alternative encryption algorithms expected to be resistant to quantum computers) will take time and some data is already exposed to “harvest now, decrypt later” risk. We consider the emerging standards and the practical, legal and governance steps organisations should take now.

In July 2026, the UK National Cyber Security Centre (NCSC) published the findings from its first government–industry post quantum cryptography migration workshop (Post-quantum cryptography (PQC) migration workshop report | National Cyber Security Centre), convened with a telecoms company and the National Cyber Advisory Board. The NCSC workshop report concluded that “no organisation can navigate the transition alone”. The report brings the issue out of the laboratory and into the boardroom: executive sponsorship, supplier coordination, cryptographic discovery and realistic delivery planning are now immediate UK business priorities.

The timing matters. The NCSC’s first milestone is now less than two years away: by 2028, large organisations, critical national infrastructure operators and businesses with bespoke IT should have defined their objectives, completed discovery and produced an initial migration plan. In parallel, the EU roadmap envisages Member States beginning the transition by the end of 2026, with critical infrastructure moving as soon as possible, and no later than 2030. For UK and European businesses, post-quantum cryptography (PQC) has therefore become a present question of cyber resilience, procurement and regulatory preparedness.

PQC is moving from a specialist concern to a mainstream cyber-resilience issue. A sufficiently capable quantum computer could break the public-key cryptography on which RSA, Diffie–Hellman and elliptic-curve systems rely. Those technologies help secure TLS (transport layer security) connections, virtual private networks, identity systems, digital signatures, code signing and many other business processes. See our article: Preparing for the Post-Quantum Cryptography Transition

The date on which a cryptographically relevant quantum computer may emerge remains uncertain. The business risk, however, is not confined to that future date. An attacker can collect encrypted information today and retain it for later decryption. This makes long-lived confidential material, including intellectual property, health and financial information, strategic communications and authentication data, a present-day risk-management priority.

For boards and senior management, the key message is straightforward: PQC migration should be treated as a multi-year technology, procurement and governance programme, not as a future software patch.

The standards landscape

The international technical baseline was established in August 2024 when the US National Institute of Standards and Technology finalised three principal PQC standards: ML-KEM for key establishment, ML-DSA for digital signatures and the hash-based SLH-DSA signature scheme (NIST Releases First 3 Finalized Post-Quantum Encryption Standards | NIST).The UK NCSC has aligned its migration advice with these standards, while European bodies are developing coordinated implementation and standardisation arrangements intended to preserve interoperability across the single market.

The existence of final algorithms does not make migration a simple substitution exercise. Products, protocols, certificates, key-management systems, hardware security modules, embedded devices and third-party services must support new schemes in a reliable and interoperable way. UK and European organisations should therefore follow NCSC, European Union Agency for Cyber Security (ENISA), EU and relevant sector-regulator guidance, while distinguishing technical standards from legal obligations and sector-specific transition expectations.

UK and EU direction of travel

The UK NCSC’s “Timelines for migration to post-quantum cryptography” (Timelines for migration to post-quantum cryptography | National Cyber Security Centre) sets indicative milestones for large organisations, operators of critical national infrastructure and businesses with bespoke IT. By 2028, organisations should define their migration objectives, complete a discovery exercise and establish an initial plan. By 2031, they should undertake early, highest-priority migrations and refine a complete roadmap. By 2035, migration across systems, services and products should be complete, subject to limited exceptions for unusually difficult technologies.

At EU level,  the EU Commission published “ A Coordinated Implementation Roadmap for the Transition to Post-Quantum Cryptography” (A Coordinated Implementation Roadmap for the Transition to Post-Quantum Cryptography | Shaping Europe’s digital future) which calls for a synchronised, risk-based transition. All Member States should begin moving to PQC by the end of 2026; critical infrastructure should transition as soon as possible and no later than the end of 2030; and broader migration should be completed as far as feasible by 2035. The roadmap links national action with wider EU cybersecurity policy and makes supply-chain coordination, hybrid solutions and protection of high-risk use cases central priorities.

These timelines do not, by themselves, create a generally applicable obligation for every private organisation. Existing requirements under frameworks such as the GDPR, NIS2 and DORA may require organisations within scope to assess quantum-related risk as part of their obligations concerning appropriate security, risk management, operational resilience and third-party dependencies. The roadmaps may also influence future supervisory expectations and assessments of the state of the art. Organisations should therefore monitor national implementation and sector-regulatory guidance rather than assume that vendor upgrades alone will discharge their responsibilities.

For most organisations, the immediate task is not wholesale replacement of cryptography; it is to establish accountable governance, identify where vulnerable cryptography is used, prioritise systems and data by risk, test migration options and engage suppliers whose products or services form part of the cryptographic chain.

European financial services: prioritising migration

In January 2026, Europol and its partners published a practical prioritisation framework for financial institutions (Joint report outlines practical approach to prioritising post-quantum cryptography migration in financial services - Framework supports early action and long-term planning as quantum computing challenges existing encryption methods | Europol). It assesses each use case by the shelf life of protected data, exposure to attackers and severity of compromise, and then balances that quantum risk against migration time, solution availability, cost and third-party dependencies. The report identifies hybrid protection for public-facing websites and removal of weak cryptographic practices as potential “no-regret” actions.

European businesses can incorporate PQC into existing risk and modernisation programmes rather than create a wholly separate methodology. Prioritisation should reflect both the lifespan and sensitivity of data and the practical lead time required to replace dependent systems.

European telecoms and digital infrastructure: testing interoperability

European telecoms operators and digital-infrastructure providers have an important role in migration testing because PQC changes must work across networks, devices, cloud platforms and customer environments. The NCSC workshop convened with a telecoms company identified coordination across interconnected organisations as a central migration challenge. The EU roadmap similarly emphasises coordinated, standardised hybrid solutions where appropriate. Experience from web deployments outside Europe also provides a useful technical warning: larger PQC keys and handshakes can expose weaknesses in middleboxes, inspection tools and legacy interfaces.

Pilots should test complete European service chains, including cross-border connections, network appliances, certificates, managed services and operational technology. Interoperability, fallback and exception management should be treated as governance issues, not merely engineering details.

Questions for boards and senior management:

• Do we know where quantum-vulnerable public-key cryptography is used across our estate and supply chain?
• Which information must remain confidential or verifiably authentic beyond the likely migration period?
• Who owns the programme, what budget and skills are required, and how will progress be measured?
• Are PQC readiness and crypto-agility included in current procurements, renewals and transformation projects?
• What interim controls apply where migration cannot yet be completed?
• How will we validate supplier claims and track standards, regulatory guidance and implementation vulnerabilities?

What should organisations do next?

Organisations do not need to predict “Q-Day” to justify action. By 2028, those within the scope of the NCSC guidance should aim to have accountable governance, a cryptographic inventory, a risk-based prioritisation methodology and an initial migration plan. They should also identify strategic supplier dependencies and embed crypto-agility into procurements, renewals and transformation projects already under way. Early preparation creates options; delay risks compressed procurement, unsupported legacy systems and an expensive final scramble.

PQC migration is a resilience programme spanning technology, contracts, data governance and operational risk. The organisations best placed for the transition will be those that can identify their cryptographic dependencies, change them safely and demonstrate a risk-based roadmap.

Organisations should now assess whether their governance, cryptographic inventory, supplier engagement and migration planning are sufficient to meet the UK and EU timelines. If you would like to discuss how these expectations apply to your organisation or develop a practical PQC transition framework, please get in touch.