Introduction
With the market-wide half-hourly settlement (MHHS) rollout now well underway, many businesses are starting to ask the same questions: what does this mean for my organisation, what changes do I need to make, and how will it impact my energy costs and operations moving forward?
We’ve put together a list of FAQs to break down the key aspects of the MHHS metering scheme, explain what businesses should expect during the transition, and answer the most common questions around compliance, smart metering, billing, and next steps.
What is the Market-Wide Half-Hourly Settlement (MHHS) in Simple Terms?
MHHS is a major change to the way electricity usage is measured and billed in the UK. Instead of estimating energy consumption over monthly or quarterly periods, energy use will now be recorded every 30 minutes through compatible smart meters.
This gives suppliers and businesses a much clearer and more accurate picture of how and when electricity is being used, leading to more precise billing and better energy management.
The change is being introduced by Ofgem as part of the UK’s wider net zero and sustainability goals, helping to create a smarter and more efficient energy system. As part of the rollout, traditional Non-Half-Hourly (NHH) meters are being phased out, meaning all new metering installations will need to be Half-Hourly (HH) compatible going forward.
Currently, 52 per cent of all non-domestic meters are smart devices. This figure is now certain to rise.
Does the Market-Wide Half-Hourly Settlement Affect All Businesses?
Yes- MHHS will eventually affect almost all businesses that use electricity, although the level of impact will depend on the type of meter you currently have installed.
Businesses that already have Half-Hourly (HH) or smart meters may notice fewer operational changes, as their energy usage is already being recorded at regular intervals. However, businesses with older Non-Half-Hourly (NHH) meters will be transitioned to HH-compatible metering as part of the nationwide rollout.
For many organisations, the transition may simply involve a meter upgrade or changes to the way energy data is collected and reported.
When is the Market-Wide Half-Hourly Settlement Happening?
The MHHS programme has been delayed from the original December 2026 target. The current industry timetable now runs through to July 2027, following Ofgem approval of a 6.5-month extension in late 2024.
Here’s an updated version of the timeline:
- 2023–2025 – System Integration Testing (SIT) for industry participants.
- April 2024 – Under P432, all new NHH CT connections must now be HH.
- Late 2024 – Suppliers expected to reduce mass agent appointments ahead of migration.
- October 2025 / May 2026 – MHHS migration activity begins across suppliers, with phased industry rollout.
- May 2027 – Target date for completion of meter migrations to HH settlement.
- July 2027 – Final MHHS programme completion and transition to the new settlement timetable.
If your existing electricity meter is not already HH, AMR, or Smart (SMETS), it is expected to require upgrading or conversion ahead of your supplier’s MHHS migration window.
Will My Electricity Bill Change Under the Market-Wide Half-Hourly Settlement?
Potentially, yes. Whilst your actual energy usage may not change, some businesses may see changes to their electricity bills under the MHHS update.
One of the main reasons for this is the way energy data will now be collected and processed. Traditionally, Non-Half-Hourly (NHH) meters operated on a much longer settlement window (up to 14 months), meaning suppliers only needed occasional meter readings to remain compliant.
However, under the MHHS update, all eligible meters will move to a Half-Hourly (HH) settlement approach, which works on a much shorter 7-day settlement window. This means suppliers and metering providers will be handling significantly more usage data, far more frequently.
As a result, businesses may notice increases in certain metering, data collection, or settlement-related charges to reflect the additional administration and data processing involved.
Will My Business Experience Any Operational Changes Under the Market-Wide Half-Hourly Settlement?
Businesses should not experience any operational changes during the MHHS update, though they may have some changes to their billing and charging (see above).
Do I Need a Smart Meter for the Market-Wide Half-Hourly Settlement?
Not necessarily- but your business will need a meter that can record half-hourly energy usage data under MHHS rules.
Both Smart meters and HH/AMR-enabled meters can do this, meaning they both meet the new settlement requirements. So, if you already have a compatible Half-Hourly (HH) or AMR meter installed, you may not need a full smart meter upgrade straight away.
However, traditional Non-Half-Hourly (NHH) meters are becoming outdated. Some can be upgraded with AMR (Automated Meter Reading) technology to send half-hourly data automatically.
Will Businesses be Forced to Upgrade Their Existing Meters?
Businesses will only need to replace their existing meters if the meter they currently have at their site/sites is not capable of sending half hourly data. These meters are often referred to as traditional or ‘dumb’ meters.
Does the Market-Wide Half-Hourly Settlement Affect Gas and Water?
The MHHS only applies to electricity meters and does not affect gas or water meters.
It is worth noting that water companies are increasingly introducing smart water meters for remote readings, leak detection, and usage monitoring, but there is currently no equivalent “half-hourly settlement” programme for the UK water industry.
In the longer term, some MHHS-style concepts could appear in the water industry, such as more frequent meter readings, smarter data collection, or time-based pricing. However, the timeline for this is much longer.
Will Businesses Benefit from Moving to Market-Wide Half-hourly Settlement?
Yes, businesses are expected to benefit from MHHS in several ways. One of the biggest advantages is improved access to energy data and greater billing accuracy.
With half-hourly (HH) metering, electricity consumption is recorded every 30 minutes rather than relying on periodic manual readings or estimated profiles. This means:
- More accurate billing with fewer estimated invoices
- Better visibility of when and how energy is being used
- Faster identification of unusual consumption or waste
- Improved budgeting and forecasting based on real usage patterns
The increased level of data can also support wider energy management initiatives. Businesses can use HH consumption data within a Virtual Energy Management (VEM) platform or energy monitoring system to:
- Track usage trends across sites or equipment
- Identify opportunities to reduce consumption and costs
- Shift usage away from peak periods where possible
- Support carbon reduction and sustainability reporting
- Improve operational efficiency through smarter energy management
Over time, MHHS is intended to create a more flexible and data-driven electricity market, helping businesses make more informed decisions about their energy usage.
What Challenges Are Businesses Facing Regarding the Market-Wide Half-Hourly Settlement?
Businesses may face a number of practical and operational challenges as the energy industry moves to the new Market-Wide Half-Hourly Settlement.
Here are the main challenges businesses are dealing with:
- Huge scale of change
Around 30 million electricity meters across the UK need to move to the new MHHS operating model. Managing a project of this size is a major logistical challenge for suppliers, meter operators, and businesses.
- Upgrading older meters
Of the 2.6 million meters in the Industrial and Commercial (I&C) market, around 900,000 are still older Non-Half-Hourly (NHH) traditional meters. These meters are not fully compatible with MHHS and will need upgrading, replacing, or reconfiguring.
- Pressure on engineering resources
There are concerns about a shortage of engineers needed to install, upgrade, and maintain meters. With so many meters requiring work at the same time, businesses may face delays in appointments and implementation.
- Data and system complexity
MHHS relies heavily on accurate and frequent data collection. This means businesses and energy suppliers must ensure their systems can handle much larger volumes of data securely and efficiently.
- Disruption to businesses
Some businesses may experience operational disruption during meter upgrades or changes, especially if site visits are required.
- Managing different meter types
While many larger businesses already use advanced digital or half-hourly capable meters, the market still includes a mix of traditional NHH meters, smart SMETS meters and advanced I&C meters as well as around 30,000 unmetered supplies.
- Dependence on smart and digital metering
The market is now heavily focused on smart and digital services:
- Around 95.7% of domestic and microbusiness meters are SMETS or traditional NHH meters requiring data and metering support.
- Advanced metering for larger I&C and SME businesses represents only 4.24% of the market, meaning many organisations are still adapting to more advanced two-way communication systems.
What Should Businesses Do Now?
Businesses should start preparing for Market-Wide Half-Hourly Settlement as early as possible to avoid delays, disruption, and potential compliance issues.
Here are the key steps businesses should take:
- Review current metering arrangements
Check whether your existing meters are compatible with MHHS requirements. Older Non-Half-Hourly (NHH) traditional meters may need upgrading, replacing, or converting.
- Plan ahead for upgrades and installations
Organising meter upgrades sooner rather than later can help avoid delays and reduce operational disruption.
- Work with an experienced metering partner
Consultus already has a framework in place with a provider to help make the transition as smooth as possible. This includes managing meter upgrades, new installations, meter conversions, software requirements and end-to-end project delivery.
- Reduce disruption to business operations
Consultus’ metering team can project manage the entire process, including handling supplier negotiations and coordinating installations, helping businesses avoid unnecessary impact on productivity.
- Improve monitoring and reporting
Businesses can also use myEnergy, Consultus’ online portal, to track energy costs and consumption data in one place. This can help organisations better understand their usage and prepare for more detailed half-hourly reporting.
- Seek expert support early
The earlier businesses engage with MHHS planning, the easier the transition is likely to be. Consultus’ metering team already has experience processing half-hourly (HH) data and can guide clients through the changes.
To learn more about the metering solutions that Consultus offer or for support with the transition to the market-wide half-hourly settlement, call 0330 808 0866 or fill out an enquiry form.