MiFIR (the Markets in Financial Instruments Regulation) and MiFID II (the second Markets in Financial Instruments Directive came into effect on 3 January 2018. Due to Brexit, the EU regulations have been onshored under the European Union (Withdrawal) Act 2018. On this page, MiFIR refers to both EU and UK MiFIR unless otherwise specified.

MiFIR and MiFID II together govern all aspects of the financial markets, including trading and reporting of financial instruments. Transaction reporting obligations are a large part of the regulatory regime and are contained in MiFIR. TRAction provides a full-service MiFIR solution that can simplify your transaction reporting requirements.
The scope of the MiFIR reporting regime includes:
- financial instruments admitted to trading or traded on an EEA trading venue or for which a request for admission to trading has been made;
- financial instruments where the underlying financial instrument is traded on a trading venue (ToTV) (guidelines state ‘underlying’ means immediate underlying instrument rather than ‘ultimate’ underlying instrument); and
- financial instruments where the underlying instrument is an index or a basket composed of financial instruments traded on a trading venue.

What is the reporting obligation?
As transaction reporting obligations are contained in the MiFIR regulation, there cannot be differing implementation between European nations. MiFIR imposes transaction reporting obligations in respect of specified transactions in financial instruments where the underlying instrument is traded on a European Economic Area (EEA) trading venue.
It is important to note that where an EU investment firm has executed its transactions via a UK branch or vice versa, the entity will have a dual reporting obligation. The FCA has made it clear post-Brexit that the branch will no longer be able to discharge the reporting obligations by transmitting orders to the other entities.
Who is required to report?
Transaction reporting obligations extend to:
- investment firms;
- investment managers providing advice and portfolio management to individuals;
- credit institutions;
- market operators;
- all financial counterparties under EMIR;
- central counterparties and persons with proprietary rights to benchmarks; and
- third-country firms providing investment services or activities within the EEA.
What to report and to whom?
There are 65 reporting fields under MiFIR, including:
- identification of the relevant parties – the legal entity, natural person or algorithm which submitted the order, made the investment decision or executed the order;
- identifying information – a Legal Entity Identifier (LEI) for legal entities and personal identification information for natural persons;
- product classification and identification – CFIs and ISINs for financial products; and
- date & time of trade – must be provided for each trade.

Firms can report directly to their National Competent Authority (NCA), or indirectly through an Approved Reporting Mechanism (ARM) or a third-party solution.
Wondering where to report your transactions post-Brexit? To an EU ARM or a UK ARM? Click here.
What are the MiFIR trade publication requirements?
The regulation requires European investment firms (IFs) to make public, through an Approved Publication Arrangement (APA), post-trade transparency information in relation to financial instruments which are traded on a Trading Venue or traded over-the-counter (OTC)/off exchange. The obligation only requires one counterparty to report the trade data.
For more information on trade publication requirements, please head to:
- Who has obligations to meet MiFIR trade publication requirements; and
- The differences between trade publication and transaction reporting in the UK and Europe.
What is a trading venue?
Under MiFID II, there are 3 categories of trading venue:
- Regulated Market
- Multilateral Trading Facility
- Organised Trading Facility
Do you know the difference? View our comparison of the three trading venues in this article.