Market-Wide Half-Hourly Settlement (MHHS)

MHHS is an industry reform led by Ofgem that will require electricity suppliers to settle all customer usage based on actual Half-Hourly (HH) data, rather than estimates. This means energy suppliers must buy and bill energy based on real-time, 30-minute usage data for every customer with a capable smart meter.

What is Market-Wide Half-Hourly Settlement in Simple Terms?

Imagine your electricity meter is like a stopwatch that tells the energy companies exactly when you use electricity - not just how much you use in total.

Right now, most businesses and homes get billed based on guesses or averages - like saying you probably use the same amount of energy every hour.

But with Half-Hourly Settlement, your meter sends readings every 30 minutes, so suppliers know exactly when you used energy.

Why is this a big deal?

  • - You can save money by using power when it's cheaper (like when the sun is shining or wind is blowing).

  • - The whole system becomes smarter, so the UK can use more green energy and waste less.

  • - You get better deals because energy companies compete more fairly based on real usage.

This change is happening across the UK and will affect everyone over the next couple of years.

Why is MHHS being introduced?

The current system often relies on estimated energy usage, which doesn't reflect real-time demand. MHHS aims to modernise the energy market by using accurate data to improve efficiency, reduce costs, and support the shift to a smarter, low-carbon energy system.

How does MHHS benefit businesses?

- More Accurate Billing - Charges based on actual usage rather than assumptions.

- Optimised Tariffs - Access to more flexible and time-of-use tariffs that reflect when you use energy.

- Cost-Saving Opportunities - Businesses can shift usage to cheaper, off-peak times.

- Supports Net Zero Goals - Encourages smarter energy usage and enables better integration of renewables.

- Enhanced Data Insights - More granular consumption data to inform energy efficiency strategies.

Do all businesses need to take action?

Not immediately - but businesses with smart meters (particularly SMETS2) will be well-positioned to benefit. Over time, the rollout will impact all electricity users. If your business hasn’t upgraded to a smart meter yet, now is a good time to prepare for MHHS.

When is MHHS being rolled out?

Migration begins in April–September 2025, with full roll‑out expected by mid‑2027. Preparations are already underway across the industry and we’re here to help you get ahead of it - so you benefit, not just react.

Does MHHS affect contracts or switching?

No - MHHS doesn’t affect your ability to switch suppliers or negotiate contracts. In fact, with more accurate usage data, it could help secure more tailored and competitive deals.

For more information, refer to: https://www.mhhsprogramme.co.uk/