Performance Assurance Parties (PAPs) can be audited as part of the BSC Audit, Technical Assurance of Performance Assurance Parties, or ad hoc audits. This page concentrates on the BSC Audit.

The BSC Audit

The BSC Audit is a key detective technique in ELEXON’s Performance Assurance Framework.

It is designed to provide assurance that the Settlement and Funding Share calculation provisions are complied with.

It is a national exercise undertaken each year by KPMG, as the current BSC Auditor, with the assistance and co-operation of many industry participants. The BSC Auditor is a BSC Agent procured and managed by ELEXON.

What happens during the Audit?

The BSC Panel sets the scope of the BSC Audit each year. Following this, the BSC Auditor develops an Audit Approach which describes how it will deliver the work required to meet the scope.

Below are copies of the current BSC Audit Scope, BSC Audit Scope Diagrams and non-confidential version of the BSC Audit Approach. Contact us if you require previous versions.

BSC Audit Scope 2015/16 [342kb]

Issued On: 28-September-2015

BSC Audit Scope 2014/15 [248 Kb]

Issued On: 10-March-2014

BSC Audit Scope 2013/14 [271 Kb]

Issued On: 30-September-2013

BSC Audit Approach 01/04/15 – 31/03/16

Issued 30-October-2015

BSC Audit Approach 01/04/14 – 31/03/15 [183 Kb]

Issued 31- October 2014

BSC Audit Approach 01/04/13 – 31/03/14 [228 Kb]

Issued 31- October 2013

BSC Audit Scope Diagrams [39 Kb]

Issued On: 11-October-2006

What happens after the Audit?

The BSC Auditor presents his Annual BSC Audit Report in June each year to the BSC Panel. This and Market Issues relating to specific market roles are located in Performance Assurance Reports. Individual and confidential Audit Issue Documents are distributed to Audited Entities. ELEXON works with those parties on resolution.

What does a ‘Qualified’ BSC Audit Opinion mean?

The BSC Auditor will ‘Qualify’ its audit opinion if it cannot provide reasonable assurance that the total level of error in Settlement is less than the Materiality Threshold. The Materiality Threshold is currently 1.4TWh which represents approximately 0.5% of the total annual electricity supplied across Great Britain.

Related Audits

The BSC Audit incorporates the Funding Shares Audit and takes account of the findings of the Balancing Mechanism (BM) Audit performed by National Grid’s Auditor. The BM Audit looks at the data submitted and used for balancing the system. You can download the BM Audit Report from the National Grid website.

I’m about to be Audited – what do I need to know?

Your OSM and the BSC Auditor will be in touch with you to discuss the audit process, and answer any questions you may have. You will be offered a planning meeting to talk about arrangements for the site visit and any data requests.

We offer an online tool, the BSC Audit Navigator, which is a secure central repository for BSC Audit documentation. You can use it to share information with the BSC Auditor and ELEXON. You can upload, view and download information relating to the Audit. If you want to use this facility please email

BSC Audit Issue Documents

Individual Issue Documents are raised by the BSC Auditor to highlight issues identified during its work. Individual documents are raised against Audited Entities: Suppliers, Supplier Agents, Supplier Meter Registration Agents, BSC Agents (in relation to the Central Systems) and ELEXON. You receive your final Issue Documents once you’ve agreed and accepted the content.

Audit Peer Comparison

During the BSC Audit Terms of Reference Review 2009, an Expert Group examined how performance under the BSC Audit could be measured, to incentivise Audited Entities to reduce non-compliances.

We put together a scoring mechanism, and compiled the results for each market role. The data from the 2013/2014 Audit Year which is published in BSC Audit Issue Resolution.