1. How UKCA and CE Mark diverged after Brexit
When the UK left the EU single market, the UKCA (UK Conformity Assessed) mark was introduced as a direct replacement for CE marking in Great Britain. For medical devices, this meant the UK Medical Devices Regulations 2002 (as amended) became the governing framework, sitting alongside — and then gradually diverging from — EU MDR 2017/745.
The early assumption was that UKCA would remain largely equivalent to CE marking, with mutual recognition agreements eventually resolving the duplication. That assumption has not materialised. As of 2026, the MHRA has implemented its own Software as a Medical Device (SaMD) guidance, updated classification rules, and established its own list of UK Approved Bodies — none of which are the same as EU Notified Bodies.
Northern Ireland continues to follow EU MDR under the Windsor Framework. Products placed on the Northern Ireland market require CE marking, not UKCA. If your distribution includes NI, your CE Mark obligations remain unchanged regardless of your UKCA status.
2. Key differences in 2026: side-by-side
The table below covers the most practically significant divergences for medical software companies seeking market access in 2026.
| Area | CE Mark (EU MDR) | UKCA (UK MDR) |
|---|---|---|
| Governing regulation | EU MDR 2017/745 | UK MDR 2002 (as amended) + MHRA guidance |
| Conformity assessment body | EU Notified Body (designated under MDR) | UK Approved Body (MHRA-designated) |
| Class IIa SaMD — third-party assessment required? | Yes — Notified Body involvement mandatory | Yes — UK Approved Body involvement mandatory |
| SaMD classification rules | MDR Rule 11 (4 risk classes) | MHRA SaMD guidance (broadly aligned, but with UK-specific interpretations) |
| AI/ML SaMD requirements | EU AI Act applies from August 2026 | MHRA AI/ML guidance (non-binding); no equivalent mandatory framework yet |
| Clinical evaluation | MEDDEV 2.7/1 Rev.4 + MDCG guidance | MHRA Clinical Evaluation guidance (similar but not identical) |
| Post-market surveillance | MDR Annex III — mandatory PMS plan, PSUR, PMCF | MHRA PMS requirements — comparable structure, different reporting timelines |
| Unique Device Identification (UDI) | EUDAMED registration required | MHRA device registration (separate UK database) |
| CE mark accepted in GB? | — | No longer accepted in Great Britain for new placements |
| UKCA mark accepted in EU? | Not accepted | — |
3. What changes specifically for SaMD
For software companies, two divergences matter most: AI/ML requirements and the classification of standalone software.
AI and machine learning
Under CE marking, your AI-based SaMD must now comply with both EU MDR and the EU AI Act — a dual-framework obligation with August 2026 deadlines, mandatory technical documentation under AI Act Annex IV, and Notified Body engagement that increasingly covers both regulations in a single assessment.
Under UKCA, the picture is different. The MHRA has published guidance on AI/ML as a medical device, but it is advisory rather than mandatory in the way the EU AI Act is. There is currently no UK equivalent to the EU AI Act's binding conformity assessment requirements for high-risk AI systems. This means the short-term documentation burden for UKCA AI/ML certification is lower — but it also means the UK framework is less predictable, as MHRA guidance can change without the formal legislative process that applies to EU regulations.
A less prescriptive UKCA AI/ML framework does not mean your product can be less rigorously validated. MHRA Approved Bodies are looking for evidence of responsible AI development even where the specific documentation requirements are not yet codified in law. Products with thin AI validation documentation are increasingly being questioned during UKCA assessments.
Classification of standalone software
EU MDR Rule 11 has a well-established interpretation framework supported by MDCG guidance documents. The UK has broadly aligned its SaMD classification with Rule 11 logic but with MHRA-specific guidance that in some cases leads to different classifications for the same product. The most common divergence occurs with clinical decision support software: products classified as Class I under EU MDR (and therefore outside Notified Body scope) have in some cases been classified as Class IIa by MHRA Approved Bodies applying UK guidance.
If your software sits near a classification boundary, you should run separate classification analyses under EU MDR Rule 11 and UK MHRA guidance — do not assume the result will be the same.
4. Do you need both marks?
The answer depends entirely on your commercial strategy, not your regulatory preference. The regulatory question is binary: if you want to sell in Great Britain, you need UKCA. If you want to sell in the EU or Northern Ireland, you need CE. There is no workaround.
The practical question is whether the investment in dual certification is justified by your revenue from each market. For most European SaMD startups, the EU market is primary and the UK market is secondary — but at 67 million people with a well-funded NHS and significant private healthcare spend, the UK is not a market to dismiss without deliberate consideration.
If you are pursuing CE marking under EU MDR, the incremental cost of adding UKCA is lower than you might expect — provided you plan for it from the start. Your ISO 13485 QMS, IEC 62304 software lifecycle documentation, and clinical evaluation can serve both certifications with relatively minor additions. The largest incremental cost is the UK Approved Body fee and the MHRA registration. Starting both processes simultaneously, rather than sequentially, typically saves three to four months of calendar time.
5. Going UKCA-only: when it makes sense
There are legitimate scenarios where pursuing UKCA before CE marking is the right commercial decision:
- NHS-first go-to-market strategy. If your initial customer base is NHS trusts or UK private hospitals and EU expansion is 18–24 months away, getting UKCA first allows earlier revenue while your EU MDR technical file matures.
- UK funding. Innovate UK grants and NHS Clinical Entrepreneur programmes sometimes require or strongly favour products with UK regulatory status. UKCA can unlock funding that accelerates EU certification indirectly.
- Lower classification in the UK. In rare cases where your product classifies higher under EU MDR than under UK guidance, UKCA-first is a faster path to market validation while your MDR Notified Body process proceeds in parallel.
UKCA-only is not a long-term strategy for most companies. The EU single market represents a combined population of 450 million with harmonised procurement rules across member states. Limiting yourself to Great Britain is a significant constraint on growth potential.
6. Timeline and practical next steps
If you are planning certification in 2026, these are the key timing considerations for each path:
CE mark timeline (EU MDR)
Notified Body capacity remains constrained. The average time from first contact with a Notified Body to completed conformity assessment for a Class IIa SaMD is currently 9–14 months, depending on the body and the completeness of your technical documentation at submission. If you need CE marking before the end of 2026, your technical file needs to be in substantially complete form now.
UKCA timeline
UK Approved Body capacity is less constrained than EU Notified Bodies, and assessment timelines for Class IIa SaMD are generally shorter — typically 6–10 months from a complete submission. However, MHRA device registration and UDI requirements add administrative steps that are easy to underestimate.
Recommended approach for dual certification
- Build your QMS to ISO 13485 with both markets in mind from the start — this requires minimal additional effort but avoids painful retrofitting later.
- Run classification analyses under both EU MDR Rule 11 and MHRA guidance in parallel before committing to a conformity assessment route.
- Select your EU Notified Body and UK Approved Body early — both have application queues and pre-submission meetings that take weeks to schedule.
- Plan your EUDAMED registration (EU) and MHRA device registration (UK) as parallel workstreams, not sequential ones.
- If pursuing AI/ML SaMD certification, build your AI Act Annex IV documentation from the start — retrofitting it into an existing MDR technical file takes significantly longer than building it in from the beginning.
UKCA and CE Mark are now genuinely different certifications requiring separate Approved Body and Notified Body engagements, separate registrations, and in some cases different documentation. They can be pursued efficiently in parallel, but they cannot be treated as interchangeable. Planning for both from day one of your certification programme costs almost nothing extra — planning for them sequentially costs months.