UK Medical Device Post-Market Surveillance Under Part 4A: An Overview

1. Key takeaways

SI 2024/1368 entered into force on 16 June 2025, inserting Part 4A (regs 44ZC–44ZR, sixteen regulations in total) into the UK Medical Devices Regulations 2002 and establishing a mandatory post-market surveillance (PMS) system for all devices on the Great Britain market. The new Part applies as one unified regime to both UKCA-marked devices and CE-marked devices, covers every device category including IVDs and active implantable devices, and offers no exemption on the ground that equivalent PMS work is already being carried out for the same products in other countries.

The practical consequence is that every manufacturer supplying Great Britain — whether it holds UKCA certification or relies on CE marking under the transitional recognition arrangements — must now maintain a documented PMS system and a PMS plan, implement preventive and corrective measures where required, report serious adverse incidents, notify field safety corrective actions, prepare the applicable periodic reports, analyse statistically significant trends and retain records in the prescribed manner. Because the scope of Part 4A is defined by the point at which a device is placed on the market rather than the point at which it was registered, products registered before the entry-into-force date remain fully in scope for as long as they continue to be placed on the market or put into service after 16 June 2025. Legacy devices cannot simply be grandfathered out of compliance, and the obligations sit alongside, rather than replace, the separate arrangements that continue to apply to Northern Ireland.

2. Legal basis

• The Medical Devices (Post-market Surveillance Requirements) (Amendment) (Great Britain) Regulations 2024 (SI 2024/1368): made on 16 December 2024; by virtue of reg 1(2) it came into force six months after the day of making, that is on 16 June 2025. reg 4 inserts Part 4A into UK MDR 2002; reg 3 amends reg 2(1), including a new definition of ‘working day’; reg 5 amends Schedule 2A; and reg 6 contains the saving provisions.
• UK MDR 2002 (SI 2002/618, as amended): the inserted Part 4A consists of reg 44ZC (interpretation), reg 44ZD (scope), reg 44ZE (PMS system), reg 44ZF (PMS plan), reg 44ZG (preventive and corrective actions), reg 44ZH (initial reports on serious adverse incidents), reg 44ZI (investigation and final reports), reg 44ZJ (FSCA and FSN), reg 44ZK (FSCA outside Great Britain), reg 44ZL (PMS report), reg 44ZM (PSUR), reg 44ZN (trend reporting), reg 44ZO (reports received by the Secretary of State), reg 44ZP (analysis of information), reg 44ZQ (retention of documents) and reg 44ZR (production of documents on request).

3. Expert insights

Insight one: Part 4A is the first substantive piece of reform of the UK device regime since the UK left the EU. Before Part 4A, the United Kingdom’s expectations on post-market surveillance remained relatively principle-based, with detailed obligations drawn largely by analogy from EU law. Part 4A now establishes a complete closed loop — system (44ZE) — plan (44ZF) — periodic reporting (44ZL/44ZM) — vigilance (44ZH–44ZK) — trend analysis (44ZN) — retention (44ZQ). Functionally, this loop is comparable to Articles 83–86 of the EU MDR, but the regulation numbers and the specific periods form a self-contained system. Compliance work must therefore be built from the UK text itself, not by transposing MDR deadlines and citations wholesale.

Insight two: the scope is defined by the point of placing on the market, not by the point of registration. Part 4A applies to all devices placed on the market in Great Britain, or put into service there, from 16 June 2025 onwards — including products that were registered before that date but continue to be placed on the market afterwards. As a result, existing products on the market cannot claim an exemption. This reading matters for manufacturers of legacy CE-marked stock: the trigger is what happens on or after the entry-into-force date, and a continuing supply flow into Great Britain restarts the obligations for each unit supplied.

Insight three: the new definition of ‘working day’ in reg 2(1) means that every deadline must be read on its own terms. SI 2024/1368 reg 3 adds a definition of ‘working day’ to reg 2(1), and reg 44ZI(3)(b) together with reg 44ZR expressly use 3 working days, whereas the 2, 10 and 15 day periods in reg 44ZH are expressed as days. The two counting bases are different, and SOPs must label them separately and never mix them. A calendar that treats a working day deadline as a calendar day deadline, or the reverse, will systematically misstate the time available, and the error usually surfaces only during an inspection or after a late submission.

4. Practical recommendations

GRZAN recommends building the PMS documentation tree by mapping each regulation from 44ZC to 44ZR in sequence: system documentation (44ZE) → plan (44ZF) → preventive and corrective action procedure (44ZG) → vigilance SOPs (44ZH–44ZK) → periodic reports (44ZL/44ZM) → trend reporting (44ZN) → retention rules (44ZQ) → response to production requests (44ZR). Every document in the tree should carry its corresponding regulation number in the header, so that the responsible person can locate the underlying requirement quickly when MHRA raises questions or conducts an inspection. As a practical estimate, most established manufacturers already hold much of the underlying content — risk management outputs, complaint files, periodic review summaries — and the main work is reorganising that material against the UK regulation numbers rather than writing new analysis from scratch. Teams should also record, for each document, the role that owns it and the review frequency, so that the system remains current as the product portfolio and complaint profile evolve over time.

5. Verification checklist

• □ PMS system documentation has been established in accordance with reg 44ZE
• □ PMS plan has been established and maintained in accordance with reg 44ZF
• □ The frequency of PMSR or PSUR preparation has been determined according to device classification
• □ Vigilance SOPs distinguish between the two counting bases of ‘days’ and ‘working days’
• □ Document retention periods have been set at 10 years or 15 years as applicable

Regulatory information verified as of 29 October 2026.

• Appointment of the UK Responsible Person (UKRP) and support with signing the letter of authorisation
• Full-process MHRA registration (DORS) filing and account lifecycle management
• Device classification determination, GMDN code selection and annual registration fee calculation
• Dual-route design for Great Britain and Northern Ireland, including UK(NI) solutions
• Establishment of post-market surveillance (PMS) systems, preparation of PMSR/PSUR and submission of vigilance reports
• Emergency handling of serious adverse incidents and field safety corrective actions (FSCA)
• Monitoring of UK regulatory changes and compliance gap assessment

For post-market compliance support in the UK market — vigilance reporting, recall management and MHRA inspection response — contact GRZAN at info@grzanglobal.com.