FCA Finalises UK Transaction Reporting Overhaul, Full Compliance Due April 2028

The UK Financial Conduct Authority (FCA) has finalised changes to the UK's MiFIR transaction reporting regime following a consultation last year. The regulator estimates that the industry currently spends £493 million annually on transaction reporting and expects the reforms to save more than £100 million a year.

The FCA described the changes as arguably the most significant to UK MiFIR transaction reporting since MiFID II came into force in 2018.

FCA: Key changes to reporting requirements

The number of reportable fields will fall from 65 to 52, and trading venues will no longer need to provide 11 instrument reference data fields. The scope of reporting will also narrow, with around seven million instruments that are tradable only on EU venues removed from UK reporting requirements.

FX derivatives will be removed from MiFIR transaction reporting altogether. The FCA considers UK EMIR a more appropriate reporting framework for this data. The change is expected to reduce costs for more than 400 UK firms while removing duplication.

The maximum period for correcting historical reporting errors will fall from five years to three. The exemption for corporate events will be widened, although IPOs, secondary offerings, placings and debt issuance will remain reportable.

The FCA has confirmed that its Financial Instruments Reference Data System (FIRDS) will become the definitive source for determining whether an instrument is reportable. A clear seven-day cut-off after execution will also apply. In practice, this should remove the need for firms to keep checking whether an instrument has entered FIRDS and become reportable after a transaction has taken place.

For derivatives on indices, where determining reportability can be difficult, firms will be allowed to voluntarily over-report these transactions.

PS26/15 also introduces a Conditional Single-Sided Reporting framework, intended to allow more firms to rely on reporting arrangements with counterparties instead of reporting the same transaction twice. The FCA noted that several buy-side respondents were sceptical about its potential benefits.

Implementation timeline

The new reporting regime will become fully effective on 3 April 2028. From 3 August 2026, the FCA will adopt a flexible supervisory approach across a defined list of areas, meaning firms will not face enforcement action for adopting several of the changes early. The shorter three-year back-reporting period also applies from this date.

In October 2026, the FCA is expected to publish a draft schema, validation rules and updated guidance, which together will form the Transaction Reporting User Pack. Until firms have access to the revised schema and validation rules, they can assess the scope of system changes but cannot begin building against the final technical specifications.

The reforms are part of a broader effort to simplify regulatory reporting in the UK. The FCA and the Bank of England have established a joint Transaction and Post-trade Reporting Industry Harmonisation Taskforce to develop a single reporting framework covering UK MiFIR, UK EMIR and UK SFTR, with the principle that firms should only have to report data once.

Although the FCA does not require firms to take immediate action, the scale of the changes and the time needed to implement them make it unwise to wait until 2028. Reporting teams and their external service providers should already be reviewing their existing arrangements, including reporting logic against the revised scope, data governance and reference data sources ahead of FIRDS becoming the definitive source, and correction and back-reporting procedures to reflect the new three-year limit.