JohnP wrote:
Realisticallty - if it was a new norm - what additional cost would it be
for new builds to have a 3 phase supply brought to the meter enclosure for
possible use for a car charger?

https://www.ssen.co.uk/ConnectionsIn...EstimatorTool/
gives 'illustrative' prices:

New supply - House/Flat

Urban single phase: £5140
Urban three phase: £9518

Rural single phase: £4017
Rural three phase: £4675

I'm guessing the urban three phase might be cheaper if you were building an
entire new street, rather than a new build slotted in between existing
houses.

Theo