Market Entry Assurance

Market Entry Assurance is the process applicants must undertake to provide assurance that their business capability can uphold market obligations. 

The MEA process consists of a series of documents applicants must complete to establish their interest in entering the market; their plan for operation; how they gained assurance and evidence on how they are able uphold their obligations; and if necessary, how they will carry out MEA testing. For further information on this process please refer to CSD 0001 (Market Entry Assurance and Market Re-assurance).

The MEA process is as follows:

1. Trading application
The Trading Application is a simple form to signal an applicant’s intent to start the MEA process. It provides MOSL with information on the applicant and their intentions within the market.

2. Application Information Return (AIR)
The Applicant Information Return (AIR) requires applicants to set out their plans for operating in the market. It includes questions regarding business structure; operating model; training; policies; procedures and systems that will be used. Not all capability needs to be in place at this stage of the process, but if it’s not, applicants need to provide dates of when it will be available to MOSL. The AIR is also where applicants decide how they will progress through the MEA process and whether they plan to go through enhanced certification or self-certification.

In order to undertake self-certification MEA, applicants must meet all of the following criteria:

  • Small scale of operations
  • Use of only the Low Volume Interface (LVI)
  • Mainly manual processes.

 If applicants are using the High Volume Interface (HVI), have a large scale of operations, and/or mostly automatic processes, they will need to undertake enhanced certification.

3. Market Entry Assurance Plan
Applicants will then set out their planned Market Entry Assurance Plan (MEAP) showing when they expect to proceed through the rest of MEA. Using the draft template above, applicants should enter their preferred training dates and when they plan to submit the rest of the documentation required. The MEAP helps applicants estimate their completion, and assists MOSL in planning for activities such as training and testing.

4. Market and Interface Training
Market and Interface Training is made up of three stages:

  • Market Training: 
    MOSL’s online Market Training will provide applicants with an overview of the market, including codes and subsidiary documents, the market framework, market entry assurance, and settlement. Applicants must complete Market Training before attending Interface Training. 
  • Bilateral Training: 
    MOSL’s online Bilateral Training will provide applicants with an overview of the Bilateral Hub, the centralised system which all trading parties use to initiate and manage bilateral transactions. Applicants must complete Bilateral Training before attending Interface Training. 
  • Interface Training:
    Interface Training is provided by MOSL and enables applicants to be trained directly on how to use the CMOS Portal (or Low Volume Interface (LVI)). All applicants must attend both stages of training, but it is particularly beneficiary for applicants who plan to only or mostly use the LVI.

Self-certification applicants

5. Self-Certification Declaration
Applicants who meet the criteria to complete the self-certification route need to complete a Self-Certification Declaration. This enables applicants to self-certify their own readiness to operate in the market. Applicants must provide assurance on a set of 36 assurance statements, confirming they have the capability in place to uphold market obligations. Applicants also need to include a third-party report, covering the applicant’s approach to assurance and the outcomes of this assurance. Any capability that was not in place when the AIR was submitted should now be ready, as applicants are providing assurance that they can operate and uphold all their market obligations.

6. Security Return
The Security Return should be submitted at the same time as the Self-Certification Declaration, for applicants going through self-certification MEA. It provides additional assurances on the applicant’s interaction with CMOS and provides evidence that they have sufficient security policies and procedures in place.

Enhanced applicants

7. Business Solution Assessment
The Business Solution Assessment (BSA) should be completed by all applicants going through enhanced MEA. It asks applicants to provide details of the approach they took to completing the assessment (which should be risk-based) and requests assurance on a set of 36 assurance statements, the assurance activities undertaken, and a view of company-specific risks considered. Like self-certification, the enhanced MEA process also asks companies to provide a third-party report. The third-party report should provide assurance on the approach the applicant has taken and on as many assurance statements as the applicant deems appropriate. Any capability that was planned but not in place for the AIR should now be implemented, as applicants are providing assurance on their ability to operate and uphold their market obligations.

8. MEA Testing
MEA Testing (MEAT) is made up of two phases; Interface and Data Transaction Testing (IDTT), which tests whether the applicant’s systems can communicate with CMOS and; Market Scenario Testing (MSR), which is a series of business scenarios likely to be used in both the market and the Bilateral Hub. Applicants need to complete both phases, but only need to carry out scenarios which involve capability to be used in the High-Volume Interface (HVI). If a scenario is intended to be carried out only using the Low Volume Interface (LVI), an applicant would not have to complete it.

The MEAT plan details how a company plans to run Interface and Data Transaction testing (through CMOS) and market scenario testing (the steps involved in switching a customer, i.e. registering a new supply point, submission of meter reads and settlement). It asks applicants to specify scenarios they will complete, the steps they will undertake in each scenario, and the exit criteria. The MEAT plan should be submitted at least 10 business days before applicants are due to begin testing. This allows MOSL sufficient time to review the plan and make amendments as required.

As part of the MEAT Plan, companies should fill in the MEA Test Script Pro-forma and Bilateral Assurance Test Script Pro-forma, where they specify scenarios they will complete, the steps they will undertake in each scenario, and the exit criteria. Once applicants have completed MEAT, they should submit a Systems Declaration to confirm the systems which were tested are those that will be used in the market. This is the last document enhanced applicants complete in the process. On acceptance of the Systems Declaration, MOSL will grant applicants with MEA Certification.

Visual representation of Market Entry Assurance process

9. MEA certification
Once an applicant has successfully completed either the self-certified or enhanced MEA process, MOSL will grant MEA certification, confirming the applicant’s capability is certified for use in the market. MOSL will also inform Ofwat that MEA certification has been granted, so they can issue the applicant with a licence to operate. 

10. MOSL Membership
Once an applicant has received their MEA certification and licence to operate from Ofwat, they should apply for MOSL membership by submitting the Accession Agreement and MOSL Membership. Once received, the board will approve or reject 

A completed copy of the Trading Party Contact details should also be provided to ensure that communications are sent to the correct persons in a timely manner. 

Related Documents

MOSL Template Accession Agreement Jan 2024


Bilateral Assurance Test Script Pro forma V1 0


MIT Declaration


Market Interface Training Wholesaler CMOS training


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