Smart Meters, Half-Hourly Settlement and What They Mean for Home Batteries
- Settlement is how suppliers are charged for what customers use. It is separate from your bill.
- By mid-June 2026, more than 11.3 million meters had moved, about a third of Britain's metering systems.
- The programme is on track to migrate all meters by May 2027, per the government's roadmap.
- Settlement does not set your tariff or change your bill by itself.
- Battery owners gain most from tariffs with different prices at different times.
Half-hourly settlement means suppliers are charged for the electricity their customers use in each 30-minute period, rather than an estimated average. Great Britain is moving every meter to it, and it is part of the groundwork for tariffs that price electricity by time of day.
What settlement is
Behind every bill sits a settlement process. The market works out how much electricity each supplier's customers used, so that suppliers can pay for it. Traditionally, for most homes this relied on profiles and estimates rather than your own half-hourly readings.
Market-wide half-hourly settlement changes the supplier's side of the arrangement. It does not, by itself, change what you are charged per unit.
Where the rollout stands
The government's Clean Flexibility Roadmap update, published on 13 July 2026, says more than 11.3 million smart meters had moved to half-hourly settlement by mid-June, about a third of Britain's metering systems. It says the programme is on track to migrate all meters by May 2027.
It also says a code change made in May 2026 stops suppliers taking on new customers if they miss the May 2027 deadline, and that a benefits plan is due by October 2026. Those are the programme's own milestones, and dates can move.
Why it matters for batteries
A battery earns its keep by moving use from expensive periods to cheap ones. That needs two things: a tariff with different prices at different times, and meter data fine enough to bill it. A smart meter can already supply half-hourly data for a time-of-use tariff today, so you do not have to wait for settlement to change before using one.
What settlement changes is the supplier's exposure. In principle, when suppliers are charged by the half hour for each customer's use, they have more reason to price and manage by the half hour as well. The roadmap says Ofgem will consult on how the price cap should adapt to half-hourly settlement, with proposals for 2027 expected after engagement over the summer.
We could not confirm which suppliers will launch new tariffs because of it. Treat any claim to that effect as marketing until the tariffs are published.
Good to know
A tariff with cheap and expensive periods only helps a battery if the gap between them is wide enough to cover losses. Check the actual rates before you commit.
What to do about it
Check that you have a smart meter and that it is working in smart mode. Ask your supplier what time-of-use or half-hourly tariffs it offers and whether export is measured. If you already own a battery, see how to earn money with a home battery on a dynamic tariff, and for how software picks charging times, read AI smart charging explained.
Common questions
Do I need a smart meter for a home battery?
Not for the battery to work. Time-of-use tariffs generally need one, though, so check with your installer and supplier.
Will half-hourly settlement raise my bill?
Settlement does not set your tariff, and the roadmap does not say it will change bills. Ofgem is consulting on how the price cap adapts, and proposals are due in 2027.
When will every meter be migrated?
The government's roadmap says the programme is on track to migrate all meters by May 2027. That is a target, not a guarantee.
Does it affect my export payments?
We could not find anything saying settlement changes export rates. Ask your supplier how your export is measured and paid.
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