SmartestEnergy begins customer migration to MHHS

SmartestEnergy has reached another important milestone in its MHHS journey, with customer migration activity now underway.

Between October 2026 and May 2027, we'll transition customers to the new Market-wide Half-Hourly Settlement (MHHS) arrangements as part of the industry's move towards a more accurate, flexible, and efficient electricity market.

We’re committed to guiding our customers through this change clearly and confidently, managing the complexity behind the scenes while keeping you informed about what matters to your business.

What does migration mean?

MHHS migration is the process of moving electricity customers from the current settlement arrangements to the new MHHS framework.

This changes how electricity consumption data is collected, processed, and settled across the market. Importantly, it won’t change your electricity supply, your contract with SmartestEnergy, or how your site is physically supplied with electricity.

How migration will take place

Customers will be migrated through four industry-defined migration sprints between October 2026 and May 2027. This phased approach allows suppliers and industry participants to manage the transition in a controlled and structured way.

We've been preparing our systems, processes and teams for migration and working closely with our industry partners to support our customers through the transition.

Your migration schedule 

All customers and TPIs should now have received communication from SmartestEnergy outlining their planned migration schedule, including:

• which migration sprint their MPANs are currently expected to migrate in.
• what to expect during the migration process.
• where to find additional support and guidance.

If you believe you should have received this communication and have not seen it, please contact your Account Manager.

What do customers need to do?

For now, there is nothing you need to do. SmartestEnergy is managing the migration process on your behalf and will contact you directly if any further information is required.

All of our customers' electricity supply, contract arrangements and agreed pricing will remain unchanged as a result of MHHS migration. As migration progresses, we’ll continue to keep customers informed throughout the transition, sharing clear guidance and updates on our MHHS journey.