The UK’s energy system is undergoing a major transformation with the introduction of Market-Wide Half-Hourly Settlement (MHHS). Starting this year and set for completion in 2027, all non-half-hourly (NHH) electricity meters will transition to half-hourly (HH) settlement. But what does this mean for your organisation?

We caught up with Jurjen de Greeve, Commercial Strategy Director for MHHS at Stark, our appointed partner for the migration of meters as part of MHHS, to break down these changes and how they will affect you.

What is Market-Wide Half Hourly Settlement (MHHS)?

MHHS is a regulatory change that will ensure all electricity meters in the UK are read and settled every 30 minutes, instead of the current estimated billing system for NHH meters. This will improve accuracy, efficiency and transparency in energy usage and billing.

Why is this change happening?

MHHS is part of the UK’s plan to modernise its energy market and support sustainability goals. By measuring energy usage more accurately, the system will be better equipped to integrate renewable energy, reduce waste and improve grid management.

How will MHHS affect my electricity bill?

Customers may see cost increases due to the higher expense of managing HH meters. Suppliers will likely pass these costs on through standing charges or additional billing line items. However, MHHS also brings opportunities for savings, with more accurate billing, improved energy insights and the potential to reduce costs by shifting usage to off-peak hours when electricity is cheaper.

What are the benefits of half-hourly metering?

• More accurate billing – Reduces estimation errors, ensuring fairer charges.
• Better energy management – Access to real-time consumption data allows businesses and households to optimise energy use.
• Increased transparency – Customers gain insight into their energy usage patterns and costs.
• Support for net zero journey – Enables smarter energy decisions and better integration of renewable sources.
• Potential cost savings – Take advantage of time-of-use tariffs and off-peak energy rates to lower your bill, such as overnight EV charging.

What challenges should I be aware of?

• Supplier readiness – Some suppliers may not be fully prepared for the transition, limiting customer options initially.
• Data collection changes – New technology will be required for accurate and frequent data processing.
• Potential cost increases – Higher monitoring and data collection costs could impact energy bills.

When is this happening?

The first wave of migrations will begin in October 2025, with additional waves every six months. By mid-2027, all electricity meters will be settled on a half-hourly basis.

What should I do next?

If your organisation is affected, it is a good idea to get ahead and prepare for the necessary upgrade to a half-hourly meter now. You’ll gain early access to the benefits half-hourly metering brings.

If you do nothing, your energy supplier will appoint an organisation to manage the upgrade for you, which may cost more and limit your ability to maximise the benefits of the transformation.

MHHS is a significant step towards a smarter, more efficient energy system. While there are challenges, the long-term benefits will support a more sustainable and transparent energy market for all.

To find out how Zenergi and Stark can streamline your transition to a half-hourly meter, get in touch today.