Data reporting

This REMIT data reporting section outlines how ACER collects data.

Under REMIT, data reporting entities are required to submit data to ACER in line with the data reporting obligations set out in secondary legislation (REMIT Implementing Regulation 1348/2014, updated in 2026).

By harmonising and standardising reporting across the EU, this centralised framework supports effective market monitoring and promotes transparency and integrity in wholesale energy markets.

The main data reporting entities under REMIT are ‘market participants’ and ‘organised market places’ (OMPs), which submit data through:

• registered reporting mechanisms (RRMs) for wholesale energy transactions (trades and orders to trade) and exposures; or
• inside information platforms (IIPs) for 'inside information'.

To comply with their data reporting obligations, market participants must first register on the European register through the national regulatory authority (NRA) of the country where they operate.

Once registered, market participants choose the appropriate reporting entity depending on the type of data to report (IIPs for inside information, RRMs for transactions and exposures). These reporting entities then transmit the data in standardised formats to ACER via its ARIS Data Collection Interface (DCI).

Market participants that want to report directly as RRMs may apply for authorisation via ACER's Centralised European Register of Energy Market Participants (CEREMP) platform.

See the document 'REMIT data: What to report and how' for details on what data to report, how and when (e.g. frequency, timeframes, channels). This also covers new obligations introduced by the recast Implementing Regulation (2026), such as ‘exposure’ reporting of market participants’ trading positions.

What are ‘market participants’, ‘OMPs’, ‘RRMs’ and ‘IIPs’?

• Market participants are persons or companies trading on EU wholesale markets, including non-EU/EEA entities.
• Organised market places (OMPs) are platforms where multiple buyers or sellers interact to trade energy products (such as energy exchanges, brokers and capacity platforms).
• Registered reporting mechanisms (RRMs) are entities that have been authorised by ACER to report REMIT data to ACER on their own behalf (their own data) or to report data on behalf of other parties (as a service). The list of approved RRMs is publicly available on ACER's website. Authorisation is only available to RRMs that were founded within the European Union.
• Inside information platforms (IIPs) are internet-based platforms where market participants have to publish information they believe fall under the ‘inside information’ definition. With the revised REMIT, IIPs have the obligation to report to ACER the inside information data disclosed on their platform, and have to undergo an authorisation process defined in the Delegated Regulation (2026).

For further details on RRMs and IIPs and related registration/authorisation processes, see the dedicated section.

Among the REMIT actors involved in the data reporting, a specific role is also assigned to the ENTSOs in the REMIT Implementing Regulation (updated in 2026).

The European Network of Transmission System Operators for Electricity (ENTSO-E) and Gas (ENTSOG) report the ‘fundamental data’ on transmission systems (e.g. generation capacity, grid availability, cross-border electricity transmission capacity, gas pipeline capacity and flows, storage levels, outages, LNG terminal use).

ACER has two main systems to collect and manage energy market data:

• ACER REMIT Information System (ARIS). This is the central hub for all data submission, used to collect and share REMIT-related data submitted by reporting entities (RRMs, IIPs, ENTSOs). 
• ​ACER Electricity and Gas Information System (AEGIS). This platform supports ACER’s wider data management tasks (beyond REMIT). Within AEGIS, the TERMINAL application is used to collect LNG market data and publish the LNG price assessment and benchmark. From October 2027, market participants will report LNG market data via registered reporting mechanisms, instead of through TERMINAL.

ACER provides guidance to help reporting parties understand how to submit REMIT data (transaction data, exposures and fundamental data), including the electronic formats to use.

The guidance documents are updated periodically (in consultation with stakeholders). They are available in the REMIT Reporting Guidance section of the REMIT Documents page, as well as on the REMIT Knowledge Base (searchable by keyword).