Simplifying UK Transaction Reporting: What Investment Firms Need to Know Ahead of the 3 April 2028 Change

At a Glance

PS26/15 finalises a streamlined UK transaction reporting regime for investment firms, trading‑venue operators and ARMs, reducing fields to 52, removing FX‑derivative reporting and shortening the default back‑reporting period to three years, with the new rules effective 3 April 2028.

The FCA is overhauling the MiFIR‑derived reporting framework to cut annual firm costs by more than £100 million. By trimming 13 data fields, dropping reporting for 7 million EU‑only instruments and exempting most corporate actions, the regulator aims to retain high‑quality market data while easing operational burden. A flexible supervisory approach will begin on 3 August 2026, giving firms time to adapt before the formal start date.

These changes create a planning and implementation workstream for system redesign, data‑mapping and governance updates. MEMA recommends that boards review whether reporting logic, incident‑management frameworks and the new Conditional Single‑Sided Reporting (CSSR) model are covered in controls, while senior managers should consider the revised back‑reporting policy and the upcoming schema consultation in October 2026.

What the Final Rules Change

Reduced data fields

The final rules cut the number of mandatory transaction‑reporting fields from 65 to 52, meaning firms must re‑configure extraction and validation routines to match the slimmer schema and test against the FCA’s forthcoming validation rules.

FX‑derivatives removed from scope

Reporting obligations for foreign‑exchange derivatives are eliminated, directly benefiting over 400 UK firms. Affected firms should update their product‑coverage matrices and confirm that no FX‑derivative trades are inadvertently routed to the reporting pipeline.

Back‑reporting period shortened

The default historical reporting window is reduced from five to three years, lowering the volume of legacy reports that may need to be resubmitted. Firms must revise retention policies and ensure that any required back‑fill aligns with the new three‑year horizon.

Conditional Single‑Sided Reporting introduced

PS26/15 creates a new CSSR framework for certain transactions, allowing a single‑sided submission where the stated conditions are met. Companies should assess whether any of their trade types qualify and embed the conditional logic into their reporting engines.

Flexible supervisory period starts 3 August 2026

The FCA will apply a flexible supervisory approach from this date until the regime’s launch on 3 April 2028, giving firms an early window to demonstrate compliance and receive guidance before the formal go‑live.

Who Must Act

The reforms apply to UK‑authorized investment firms that submit MiFIR transaction reports, operators of UK‑based trading venues and approved reporting mechanisms (ARMs). The scope also covers market participants that provide instrument reference data or order‑book data to the FCA. Firms affected by FX derivatives, most corporate actions or EU‑only instruments should assess how the final scope changes affect their reporting processes.

While the FCA invites comment on the draft schema and validation rules in the October 2026 consultation, the final rules are binding for the groups listed above. The FCA says affected firms should begin planning now; the implementation period runs from 3 August 2026 to the new regime’s 3 April 2028 start date.

Board Assurance

The board should ask whether the firm’s current transaction‑reporting architecture can accommodate a reduced field set and the new CSSR logic without extensive re‑coding. Evidence includes a gap analysis of existing data feeds, a prototype test against the draft schema and a risk assessment of any residual reporting gaps that could affect market‑integrity monitoring.

A second board question concerns the adequacy of the incident‑management framework under MAR 14.15.5G in light of the simplified regime. The board should request documentation that the framework now covers the three‑year back‑reporting window, the conditional reporting triggers and the removal of FX‑derivative reporting, and that escalation procedures are aligned with the flexible supervisory period beginning 3 August 2026.

For PS26/15, MEMA recommends that the board record the evidence considered, the challenge raised, each agreed action owner and the next test date. That creates a traceable governance record and shows whether the agreed action improved the intended outcome rather than merely closing an administrative task.

Implementation Dependencies

From a systems perspective, the reduction in fields and the new CSSR model mean that data‑mapping tables will need to be rebuilt. Firms should inventory current field feeds, identify the 13 fields slated for removal and confirm that downstream risk‑ and finance‑systems can operate without them. Parallel testing against the draft schema, once published in October 2026, will be essential to avoid last‑minute rework.

Governance will require an update to the incident‑management framework referenced in MAR 14.15.5G. Boards should ensure that the framework captures the reduced scope, the three‑year back‑reporting rule and the conditional reporting triggers. Senior managers must sign off on revised policies, and the compliance function should schedule a risk‑based review of breach‑notification thresholds, even though the FCA is not adding a new materiality threshold at this stage.

For PS26/15, begin with the decision that the approved source actually requires and the evidence available to the firm. Link each action to the affected process, accountable owner and assurance test, while recording assumptions that still require legal or operational confirmation. Keep PS26/15: Improving the UK transaction reporting regime with the working papers so the source boundary remains visible throughout implementation.

Implementation Priorities

Source Evidence

Plain English Glossary

• PS - Policy Statement. FCA publication confirming final rules following consultation, typically with the new Handbook text and feedback summary.

Disclaimer

This article is for general information only and does not constitute legal or regulatory advice. Firms should assess the application of regulatory requirements by reference to their permissions, products, customers and operating model.

How MEMA Can Help

MEMA can help firms translate regulatory change into practical controls, policies, monitoring activity and board evidence. Book a free scoping call to discuss what this development means for your firm.

MEMA helps firms apply regulatory developments through its ongoing FCA compliance support.

Further reading: the FCA's 2026 compliance priorities.