You may already be aware that Market-wide Half-Hourly Settlement is the biggest change to impact the energy industry since privatisation. But do you know what’s happening when?

In my previous blog, I shared a ‘big picture’ overview of what Market-wide Half-Hourly Settlement – or MHHS for short – is all about.

But in response to so many questions about the MHHS timeline, I’m going to share more details about the key dates as we understand them today - to give you a better idea.

Like an iceberg

First off, it’s important to note that as far as energy consumers are concerned, not much will appear to be happening across the industry until April 2025.

Depending on your energy supplier’s migration plans, you may then start to see changes to the way your electricity supply meter is classified and the terminology on your energy invoices.

Further out, once MHHS has been fully implemented, there is the potential for greater data insight (for those who don’t currently have access to half-hourly data) and new products and services to emerge.

But between now and next spring, MHHS is rather like an iceberg – not much is visible on the outside but there is lots going on beneath the surface.

All industry participants are busy working behind the scenes to get ready for the internal industry changes that MHHS will require. And it’s these milestones that I’ll outline here.

This summer: getting ready to ‘qualify’

Suppliers are preparing to qualify under the new requirements for the industry system architecture and processes outlined by the MHHS programme.

As this involves the whole electricity industry, qualification will be phased through 2025 and 2026.

Once ‘qualified’, migration to the new MHHS model can commence. When you as a customer migrates will depend on when your energy supplier qualifies.

At nBS, we’ll find out over the coming months when we will be able to start migration.

April 2025: systems go live

By next spring, all the supporting central industry systems will be live and ready for meter migrations to begin.

April 2025: migration starts

This is the earliest that any newly qualified suppliers can start working with the central industry-wide systems to begin migrating their customer meter details (MPANs).

 But as above, each supplier will have their own migration timescales, depending on when they qualify.

This migration process is unlikely to result in any physical meter changes for customers.

However, you may potentially start to see new terminology on your energy invoices. But any changes will be fully explained in advance.

October 2026: migration complete

By October 2026, all suppliers should have migrated all their customer meters (meter point administration numbers - also known as MPANs).

In addition to new energy invoice terminology, customers should also be aware of any other changes that may result from MHHS. Again, anything new will be communicated in advance.

Hear from the experts

If you want to know more about the wider MHHS project – including key changes and potential benefits for business consumers – watch our webinar on demand from Tuesday 16 July at 10:30.

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