UMS Metering Systems (P434)

Half-Hourly Settlement for Unmetered (UMS) Supplies (P434) is an industry modification that requires all Non-Half-Hourly (NHH) MPANs to be Half-Hourly (HH) settled via a Change of Measurement Class (CoMC), by the mandated Completion Date of 31st March 2025.

Additionally, by 1st April 2025, all NHH UMS MPANs must be removed from the industry. This modification is a pre-cursor for the Market-wide Half-Hourly Settlement programme.

There are two main reasons for P434. The first, is to provide greater accuracy in Settlement & Billing for customers. The second, is to help support the nation in its Net Zero ambition. For our customers, this modification will:

• Provide more accurate bills due to the increased nature of reads.
• Provides less invoices due to NHH consolidation into HH.
• Improve our customers portfolio awareness.

If you are an impacted customer, to proceed with this modification, what you need to do first is to understand your current NHH portfolio (how many NHH meters you have). Once you have assessed your portfolio, please decide on how you wish to progress.

There are 4 ways to proceed with this modification:

1.  Match all Non-Half Hourly Supplies with a new Half-Hourly UMS MPAN
2.  Merge groups of Non Half-Hourly UMS into 1 or more Half-Hourly MPAN(s) 
3.  Move all Non Half-Hourly supplies volume into current Half-Hourly UMS MPAN
4.  Move all Non Half-Hourly supplies volume into NEW Half-Hourly UMS MPAN