MHHS Migration Waves: Are You Ready?
MHHS migration is underway.
If your metering estate isn’t ready, you’ll pay the price in manual read charges and estimated bills.
The industry’s biggest transformation in decades is no longer on the horizon – it’s happening now.
Market-wide Half Hourly Settlement (MHHS) migration launched in October 2025, and every electricity supply in the UK will move to the new system by May 2027.
The question is: will your supplies migrate smoothly, or will you face costly disruption?
What MHHS migration involves
MHHS Migration isn’t a simple flip of a switch. It’s a structured process that moves your electricity supplies from the current settlement system to the new MHHS framework.
During migration, existing Data Collectors and Meter Operators will be deappointed from the old system and reappointed to the new MHHS system.
Your Supplier and their agents coordinate this transition.
But the readiness of your metering estate determines whether the process runs smoothly or becomes expensive.
Understanding the MHHS migration waves
MHHS migration is delivered in waves.
Each Supplier is assigned to a specific wave and must migrate all customer supplies in a defined window.
Your migration timing depends entirely on which wave your Supplier is in.
You can use this information now.
Check the MHHS Programme’s “Facilitating Engagement between Suppliers and Agents Central Register” to confirm your Supplier’s wave assignment.
- The supplier must submit MPANs to the programme.
- Customers can request this if needed.
- Once submitted, Suppliers have 9 months to migrate those MPANs, with most migrations happening in the first 6 months of the programme.
What you must do
Here’s the reality: poor metering infrastructure means expensive migration.
If your meters can’t provide Half Hourly data remotely, you’ll face:
- Increased manual read charges because someone must visit your meters more often
- Estimated bills that typically overcharge
- Compliance risks because manual reads won’t meet MHHS data quality targets
- Lost Time of Use savings due to missing accurate consumption data
Get Your Data & Metering Partners Ready Now
Your Data Collector and Meter Operator must be MHHS-qualified. This is not optional.
Your action list:
- Confirm your Supplier’s migration wave
- Audit your metering estate (Traditional, Advanced, and Smart)
- Upgrade or replace meters that can’t provide remote Half Hourly data
- Verify your data & metering agents are MHHS-qualified
- Update your site contact details with your Metering agent
Without this preparation, you’re heading into migration blind.
Why Data Quality matters more than ever
Under MHHS, data quality directly impacts your costs.
Poor data means estimated bills, manual read charges and missed opportunities to optimise consumption.
Your choice of Data Collector and Meter Operator is now critical.
Stark is the best-performing Data & Metering combination for settlement data in the market. We’re the only agent who can dial all meter types, fully qualified for all MHHS services, and we put data quality first.
When you combine Stark Data with Stark Connect:
- Fewer manual read charges
- Accurate billing based on actual consumption
- MHHS-ready infrastructure
- Single point of contact for all your data and metering needs
Our data quality is consistently above industry standards because we’ve been doing this for over 40 years. We deliver the data you need, when you need it.
The cost of waiting
Every day you delay increases your risk.
If your metering estate isn’t ready when your Supplier’s wave arrives, you won’t have time to fix it. You’ll be migrated with whatever infrastructure you have – working or not.
That means months of estimated bills, unexpected manual read charges, and no way to unlock the Time of Use savings MHHS data promises.
What happens next?
Migration is underway. Your Supplier has a wave assignment. Your meters need to be ready.
Don’t wait until the last minute.
