Changes to the top line of your MPAN of your electricity meter
As part of MHHS, the top line of your MPAN electricity meter will have changed from September 2025. Read more about the MPAN top line changes.
What is Market-wide Half-Hourly Settlement?
Market-wide Half-Hourly Settlement (MHHS) is an industry-wide reform designed to modernise the UK electricity market. Electricity suppliers will use half-hourly data to settle energy more accurately with the grid. This helps the energy system run more efficiently and supports the UK's move towards Net Zero.
Smarter for your business, better for the planet.
How can MHHS benefit my business?
Market-wide Half-Hourly Settlement is designed to make the UK’s electricity system smarter and more efficient by settling energy use every 30 minutes.
Improve accuracy
Suppliers can match what customers use with what's bought on the grid more closely.
Unlock more renewable energy
Making it easier to bring wind and solar power into the system.
Support Net Zero goals
Helping the UK cut carbon and move towards a greener energy grid.
Open the door to future opportunities
Such as new tariffs and tools to give clearer insights into how your business uses energy.
According to Ofgem, MHHS is expected to deliver net benefits for consumers in Great Britain of £1.6 billion to £4.5 billion from 2021 to 2045. This marks a significant step toward a smarter, more sustainable energy system.
How does Market-wide Half-Hourly Settlement work?
Today’s approach
Most customers are settled on estimates based on profiles, not real-time data. This means suppliers often rely on forecasts that don’t fully reflect when and how energy is used.
With MHHS
Meters will provide half-hourly readings, so suppliers and the grid know exactly when energy is consumed. This real-time insight helps the whole system run more efficiently.
Our key Market-wide Half-Hourly Settlement milestones
Here's the timeline we're working towards for our business electricity customers.
MPAN top line changes
From September 2025, the MPAN top line of your electricity meter will have changed. Read more about the MPAN top line changes.
British Gas business transition begins
From August 2026, we’ll begin transitioning our customers’ meters to the new MHHS half-hourly settlement process.
All meters moved to half-hourly settlement
All energy suppliers, including us, will need to have moved to the new half-hourly settlement process by May 2027.
Changes to the MPAN top line of your electricity meter
From September 2025, the MPAN top line of your electricity meter will look slightly different on your bills and contracts.
- The Meter Time Switch Code (MTC) will be replaced with the 4 digit Standard Settlement Configuration ID, which will show as '0000' if not applicable.
- The Line Loss Factor Class (LLFC) ID is being replaced with a Distribution Use of System (DUoS) Tariff ID. DUoS charges fund the local electricity network costs.
Don't worry, any business electricity contracts or rates won't change.
Get ahead and request a business smart meter
Smart meters provide the half-hourly data that the new MHHS system uses - helping to make energy settlement more accurate and supporting a smarter, greener grid.
Our existing customers can request a smart meter upgrade today.
Understanding MHHS
What is the Market-wide Half-Hourly Settlement (MHHS)?
Market wide half-hourly settlement (MHHS) will modernise the UK electricity market. It's a regulatory programme, aimed at supporting the UK's transition to Net Zero by introducing half-hourly settlements. Electricity readings will be sent every 30 minutes, giving your business a clearer view of usage.
How will MHHS work?
Electricity suppliers have traditionally estimated customer energy use based on average consumption patterns. The new MHHS system replaces this with a smarter, data-driven approach. By using actual half-hourly data, suppliers can now match the electricity they buy with what you use in real time, every 30 minutes, instead of relying on a one-size-fits-all estimate. Ofgem, the UK's energy regulator, oversees the programme.
What are half-hourly settlements?
Half-hourly settlements track your electricity use every 30 minutes. It's about us paying the grid for the energy that's being used. It's a smarter way to manage energy helping you take control of costs and make the most of off-peak savings.
What is Net Zero and what role does MHHS play in achieving Net Zero?
Net Zero is all about balancing emissions we put into the atmosphere with the amount we remove. It's a key driver in our efforts to fight climate change, and the UK is committed to reaching Net Zero by 2050.
The MHHS Programme is core to this plan. By switching to half-hourly settlements, energy suppliers can accurately track and settle electricity usage in real-time. This will encourage us to be more mindful of our energy use, helping us to shift consumption to off-peak times when there is more renewable electricity available. Overall, the MHHS Programme not only promotes energy efficiency but also contributes to a more sustainable energy system, driving us closer to our Net Zero goals.
Is it mandatory for energy suppliers to transition to the new MHHS arrangements?
Yes, the transition to the MHHS arrangement is mandatory for all energy suppliers. Different suppliers will start transitioning their customers at different times. We'll keep you informed if there are any important changes you need to be aware of.
As part of MHHS, will the MPAN top line of my electricity meter change?
Yes, the MPAN top line of your electricity meter will change to include new data points.
The Meter Time Switch Code (MTC) will be replaced with the 4 digit Settlement Configuration (SSC) ID.
The Line Loss Factor Class (LLFC) ID is being replaced with a Distribution Use of System (DUoS) Tariff ID. DUoS charges fund the local electricity network costs.
This MPAN change won't affect your current contract or rates.
Customer actions
Do I need to do anything to prepare for MHHS as a customer?
We've got it all in hand. All preparations and updates needed for this transition will be handled by us. We'll let you know if anything changes, or if there is anything you need to do.
What if my business doesn't have a smart meter?
All meter types are included in MHHS smart, advanced, and traditional. You don't need to do anything now, but having a smart meter will help you benefit sooner if new products become available.
When you log into your online account to submit a meter reading, you'll be asked if you want to upgrade to a smart meter once you submit your latest reading.
What if I switch supplier during the transition?
You'll still be covered. MHHS includes processes to ensure switching suppliers is seamless, whether your meter has been changed to MHHS with your previous business energy supplier or not.
Billing & usage
How will MHHS change the way my electricity usage is calculated?
Instead of using estimates, MHHS uses actual half-hourly readings from your meter. This gives a more accurate picture of when you use energy and helps the system run more efficiently.
Will MHHS change how I’m billed if my usage varies throughout the day?
If you’re on a time-of-use tariff, like PeakSave for business, your bills will reflect when you use energy, as they do now. For other tariffs, MHHS won’t change your pricing, it just makes settling your meter readings more accurate behind the scenes.
When will I see a change in my bill?
As part of MHHS, the MPAN top line of your existing electricity meter will change in your business electricity bills after September 2025.
We're working on the MHHS transition for August 2026. If your bill changes before then, we’ll let you know - and we’ll keep you updated as we get closer to the switch.
Will MHHS affect my current contract or prices?
No. Your agreed contract terms and prices will stay the same until your renewal date. MHHS will not add any new charges during your contract.
Will MHHS affect my business gas contract?
No. MHHS only applies to business electricity meters.
What if I already have a half-hourly meter?
If you’re already settled half-hourly, nothing changes for you. MHHS simply standardises this approach across the market.
