Harmonized standards are the most practical tool available to a MedTech startup for demonstrating compliance with MDR. When you follow a harmonized standard, you get a "presumption of conformity". The assumption, rebuttable but strong, that you have met the corresponding MDR requirements. Without harmonized standards, you would need to demonstrate compliance with every applicable GSPR from first principles. With them, you have a recognized, accepted path.
But here is the problem that has plagued the MDR transition: the harmonization of standards under MDR has been dramatically slow. Many standards that were harmonized under the old MDD have not yet been harmonized under MDR. This creates a gap. The standards exist, the industry uses them, but they do not carry the formal presumption of conformity under MDR.
This post maps the landscape of harmonized standards under MDR as of 2026, explains what the gaps mean, and provides practical guidance for startups navigating the situation.
How Harmonization Works
A standard becomes "harmonized" under MDR through a specific process:
- The European Commission issues a standardization request to the European Standardization Organizations (CEN, CENELEC, ETSI)
- The ESOs develop or adopt the standard (often based on international ISO/IEC standards)
- The standard is assessed for alignment with MDR requirements
- If it aligns, its reference is published in the Official Journal of the European Union (OJEU)
- Once published in the OJEU, following the standard creates a presumption of conformity with the specific MDR requirements (GSPRs) it covers
A standard that is NOT published in the OJEU under MDR is NOT harmonized under MDR. Even if it was harmonized under MDD, and even if it is widely used in the industry. This distinction is crucial.
The Harmonization Gap
When MDR came into application on 26 May 2021, the number of standards harmonized under MDR was very limited compared to the hundreds that had been harmonized under MDD. This "harmonization gap" has been one of the most discussed challenges in the MDR transition.
The gap exists because: - MDR changed many requirements compared to MDD, and standards needed to be revised to align with the new requirements - The assessment process for verifying alignment between standards and MDR GSPRs is time-consuming - The European Commission and the ESOs have a formal process that cannot be rushed without risking quality
By 2026, the situation has improved significantly, but gaps remain.
Key Standards and Their Harmonization Status
Here are the most important standards for MedTech startups and their current harmonization status under MDR:
Quality Management
EN ISO 13485:2016. Medical devices. Quality management systems. Requirements for regulatory purposes The foundation of your QMS. This standard has been harmonized under MDR. Following it creates a presumption of conformity with the QMS requirements of Article 10(9).
Risk Management
EN ISO 14971:2019 + A11:2021. Medical devices. Application of risk management to medical devices The core risk management standard. Check current harmonization status. The 2019 edition with the A11:2021 amendment has been aligned with MDR's risk management requirements.
Software
EN 62304:2006 + A1:2015. Medical device software. Software life cycle processes Essential for any software medical device.
Usability
EN 62366-1:2015 + A1:2020. Medical devices. Application of usability engineering to medical devices Usability engineering is required by MDR GSPRs.
Biocompatibility
EN ISO 10993 series. Biological evaluation of medical devices A series of standards covering biological evaluation, cytotoxicity, sensitization, irritation, systemic toxicity, and more. The harmonization status varies by part.
Electrical Safety
EN 60601-1:2006 + A1:2013 + A2:2021. Medical electrical equipment. General requirements for basic safety and essential performance The foundational electrical safety standard for active medical devices.
EN 60601-1-2:2015 + A1:2021. Electromagnetic compatibility EMC requirements for medical electrical equipment.
Clinical Evaluation
EN ISO 14155:2020 + A1:2024. Clinical investigation of medical devices for human subjects. Good clinical practice If you are conducting a clinical investigation, this is the standard for GCP compliance.
Sterilization
EN ISO 11607 series. Packaging for terminally sterilized medical devices EN ISO 11135. Sterilization of health-care products. Ethylene oxide EN ISO 17665. Sterilization of health-care products. Moist heat
Labeling and Symbols
EN ISO 15223-1. Medical devices. Symbols to be used with information to be supplied by the manufacturer Symbols used on medical device labeling.
What to Do When a Standard Is Not Harmonized
If a standard you rely on is not (yet) harmonized under MDR, you can still use it. You just do not get the automatic presumption of conformity. Here is the practical approach:
1. Apply the standard anyway. A well-recognized international standard, even if not formally harmonized, provides strong evidence of compliance. Notified Bodies and competent authorities understand the gap and accept non-harmonized standards as evidence. They just assess the evidence more carefully.
2. Document the relationship. In your GSPR checklist, reference the standard and explicitly explain how it covers the relevant GSPR. Map standard clauses to GSPR requirements. This mapping demonstrates that you have thoughtfully used the standard as evidence, not just listed it.
3. Supplement where needed. A non-harmonized standard may not cover every aspect of the MDR GSPR it relates to. Identify any gaps between the standard's requirements and the GSPR, and address them with additional evidence.
4. Monitor for harmonization. Standards are being harmonized on an ongoing basis. When a standard you are using becomes harmonized, update your GSPR checklist to reflect the presumption of conformity.
Tibor's practical view: "The harmonization gap is a bureaucratic problem, not a technical one. The standards themselves are good. They represent the state of the art. Whether or not they are officially harmonized under MDR, using them is the right thing to do technically. The paperwork around mapping them to GSPRs is slightly more work than citing a harmonized standard, but it is not a barrier to certification."
How to Check the Current Harmonization Status
The definitive source is the Official Journal of the European Union (OJEU). The Commission publishes and updates the list of harmonized standards under MDR through implementing decisions.
Practical sources for checking harmonization status: - EUR-Lex (the EU's legal database). Search for implementing decisions on harmonized standards under Regulation (EU) 2017/745 - European Commission standardization page for medical devices - CEN/CENELEC websites. The ESOs maintain lists of standards under harmonization requests - Notified Body guidance. Your NB can confirm which standards they accept as harmonized
Using Standards Strategically
For a startup, harmonized standards are not just compliance tools. They are strategic assets:
They Simplify Documentation
A GSPR checklist entry that says "Conformity demonstrated through EN ISO 14971:2019 + A11:2021 (harmonized)" is simpler than an entry that requires a custom justification of how your proprietary risk management approach meets GSPR requirements.
They Reduce Notified Body Review Time
When the NB sees harmonized standards in your GSPR checklist, they know the path. The review is faster because the evidence framework is recognized. Novel approaches require more NB time to assess. Which means more cost and longer timelines.
They De-Risk Your Certification
If you follow a harmonized standard and the NB accepts it, a market surveillance authority would need to challenge the standard itself (or your application of it) to question your compliance. This is a much higher bar than challenging a custom compliance approach.
They Provide Structure for Testing
Harmonized standards define test methods, acceptance criteria, and reporting requirements. For a startup that has never tested a medical device, the standard tells you exactly what to do. Without it, you would need to define your own test methods and justify them. A harder task.
The Full Landscape
Beyond the key standards listed above, dozens of standards cover specific device types, specific test methods, and specific aspects of medical device development and manufacture. The full landscape includes:
- Particular standards (IEC 60601-2-xx series). Device-specific safety standards for particular types of medical electrical equipment
- Performance standards. Standards defining performance requirements for specific device categories
- Process standards. Standards for specific manufacturing and quality processes (sterilization, packaging, cleaning)
- Environmental and shelf life standards. For stability and transport testing
Identifying which standards apply to your specific device is part of your regulatory strategy. The GSPR checklist drives this identification: for each applicable GSPR, identify the relevant standards and assess whether they are harmonized.
The Bottom Line
Harmonized standards are the startup's best friend in MDR compliance. They provide recognized, accepted paths to demonstrating conformity. They simplify documentation, speed up NB reviews, and reduce certification risk.
The harmonization gap has been a challenge, but it is closing. In 2026, many key standards are harmonized, and the rest can be used with appropriate documentation and mapping.
Your action items: 1. Identify all standards relevant to your device 2. Check their harmonization status against the current OJEU listings 3. Use harmonized standards wherever possible. They are the most efficient path 4. For non-harmonized standards, document the GSPR mapping carefully 5. Monitor harmonization updates. The landscape is evolving
Standards are not bureaucratic overhead. They are accumulated engineering wisdom, codified into practical requirements. Use them.