Audits and checks

This page explains the different types of audits and checks we use to monitor risks to Settlement.

Annual audits

Every year, Elexon carries out two audits of participants in the energy market:

• The BSC Audit, a process audit that checks whether participants are meeting their obligations under the Code
• The Technical Assurance of Metering (TAM) Audit, which checks that metering systems are installed and maintained correctly

Additional checks that may be needed

When we need additional information on a particular activity, process or risk, we may carry out targeted assurance checks:

• Assurance Information Request (AIR) – a formal request for specific information
• Technical Assurance of Performance Assurance Parties (TAPAP) – a more in-depth review of how obligations are being met

Assurance Information Request (AIR)

An Assurance Information Request (AIR) is a formal request from Elexon asking a Party or Agent to provide specific information that helps assess whether they’re meeting their BSC obligations and managing Settlement Risks effectively.

AIRs are typically issued when something looks unusual—such as missing data, repeated estimation, or a process failure—and Elexon needs more detail to understand the situation.

Example:
If a Supplier has a high number of estimated meter readings, Elexon might issue an AIR asking:

• which meters are affected
• why actual readings couldn’t be obtained
• whether there were system or agent issues
• what’s being done to fix the problem

This helps Elexon decide whether further action is needed to protect Settlement accuracy.

Technical Assurance of Performance Assurance Parties (TAPAP) check

A TAPAP check is a more in-depth review carried out by Elexon (or on its behalf) to assess how well a Party is meeting specific obligations under the BSC.

It can involve interviews, process walkthroughs, and document reviews to check that a process—like data collection, meter operation, or submissions—is being done correctly.

Example:
Elexon might carry out a TAPAP check to confirm that a Party is:

• correctly operating Half Hourly meters
• following procedures for data validation
• applying the right rules for estimating missing data

TAPAP checks are usually targeted, based on identified Settlement Risks, and findings are reported to the Performance Assurance Board (PAB).

Learn more or take action

• BSC Audit information (SOFY)
• TAM audit information (TAAMT)
• Non-compliance