Energy & utilities · UK
Half-Hourly Settlement
Every electricity meter in Great Britain moves to settlement on actual half-hourly readings, replacing estimates.
ForSettlement and metering leads at electricity suppliers, and their data service providers.
What’s changing, and when
Since 22 October 2025, suppliers have been moving their customers' meters to market-wide half-hourly settlement, which uses actual half-hourly consumption instead of estimates. Migration of every meter completes by 7 May 2027, and old and new settlement run side by side until July 2027. On 2 July 2027 settlement cuts over to a shorter timetable of about four months instead of fourteen.
- Oct 2025 Meter migration starts
- May 2027 Every meter migrated
- Jul 2027 Shorter settlement timetable begins
Why it can’t happen in one step
Millions of meters move supplier by supplier, so old and new settlement run in parallel and every reading has to reconcile across both.
How Polymonial carries you across
- Meter readings that cannot be quietly altered, from meter to settlement.
- Old and new settlement keep working together until every meter has moved.
- Readings reach only the parties entitled to them.
Trust that travels.
Secure, trusted and under your control.