Platforms · Software · Providers · Markets
The FCA has finalised a redesign of UK MiFIR transaction reporting after consulting last year. The regulator puts firms' current annual reporting bill at £493 million and forecasts savings of more than £100 million a year under the new rules.
The regime is due to switch fully on 3 April 2028. Some changes can be adopted earlier, with the FCA taking a flexible supervisory approach from 3 August 2026 in specified areas. The shorter limit for correcting old reports also applies from that date.
For retail FX and CFD brokers, the removal of FX derivatives from UK MiFIR is a central change. The FCA points to UK EMIR as the appropriate place for this data, ending duplicate reporting across the two regimes. It expects the shift to cut costs for more than 400 UK firms.
What changes in transaction scope
- Fewer fields. The number of data fields firms must submit drops from 65 to 52. Trading venues will no longer have to supply 11 instrument reference data fields.
- A smaller instrument universe. Around seven million instruments available only on EU venues will leave the UK reporting perimeter.
- Different treatment for derivatives. FX derivatives will no longer sit in UK MiFIR transaction reporting. For derivatives linked to indices, firms may report transactions voluntarily rather than build logic to distinguish those that fall outside the rules.
- Less time for corrections. The look-back window for fixing past reporting errors contracts from five years to three. The FCA is also widening the corporate events exemption, while IPOs, secondary offerings, placings and debt issuance remain within reporting requirements.
- A reference-data cut-off. The Financial Instruments Reference Data System, or FIRDS, will determine whether an instrument is reportable. A seven-day cut-off after execution is intended to give firms a clear point at which to assess that status.
How reference data and delegation change
Making FIRDS the authority for reportability should remove the need to keep checking whether an instrument became reportable after a trade. That puts more weight on knowing how reference data reaches reporting systems, how often it is updated and who owns its quality inside the firm.
PS26/15 also creates Conditional Single-Sided Reporting, allowing more firms to depend on a counterparty's reporting arrangement instead of submitting the same transaction themselves. The FCA heard scepticism from some buy-side respondents. Delegation still depends on reliable data exchange, explicit allocation of duties and contracts that support the arrangement, so firms will need to establish whether the conditions are workable in their relationships.
The FCA and the Bank of England have set up the joint Transaction and Post-trade Reporting Industry Harmonisation Taskforce. It is tasked with developing one framework spanning UK MiFIR, UK EMIR and UK SFTR, with the aim of limiting repeat submissions. Finance Magnates reported that the FCA expected to publish a draft schema, validation rules and revised guidance in October 2026 as the Transaction Reporting User Pack. Firms cannot build against final technical specifications until those materials are available.
Where this lands in the stack
For reporting and engineering teams, the immediate task is to map which feeds, classification rules and correction processes depend on the current scope. Check where FX derivatives are reported today, how instruments traded only on EU venues are identified, and whether the three-year correction limit is reflected in procedures already in use.
FIRDS also raises practical ownership questions: which system supplies the reference data, when does it refresh, and which team is accountable for exceptions? For Conditional Single-Sided Reporting, firms should establish what data must pass to a counterparty, how responsibility is recorded and what contractual terms are required. The answers will determine whether delegation reduces duplicate work or adds new checks.
When the October 2026 technical pack is available, firms can compare its schema and validation rules with their existing reporting interfaces and plan the changes and testing needed before 3 April 2028. The FCA has not required immediate action, but the scope of the work depends on firm-specific systems and arrangements. Teams should establish what must change before the implementation date rather than assume the reduced field count will deliver savings by itself.
