Horsham or Billingshurst: Which Grid Operator Serves You?

Most people never need to know which company runs the cables to their house. If you are adding solar panels or a battery, you do, because that company, the distribution network operator, approves the connection. In Horsham district the answer depends on where you live, because the boundary between two operators runs through it.

Our postcode checks, using Octopus Energy's public grid supply point data, put Horsham town (RH12 and RH13) on UK Power Networks' South Eastern network. Billingshurst (RH14), a few miles to the south-west, is on SSEN's Southern network. Further west in West Sussex, Chichester, Bognor Regis, Midhurst and Petworth are SSEN too, while Worthing and Crawley are UKPN.

You can check your own home in a minute. Find the MPAN on your electricity bill, the long number usually shown in a grid with an S. The first two digits of the core number are the distributor ID: 19 means South Eastern, which is UK Power Networks, and 20 means Southern, which is SSEN. If your home is on an independent network, you will see a different code, and the installer should confirm the details.

Why does it matter? First, paperwork. A solar-only system up to 3.68kW per phase is notified under G98 after installation, but a battery or larger system needs a G99 application approved before fitting. That application goes to your operator, and each runs its own process, so your installer needs to know which one before booking a date.

Second, export rates. Octopus sets some tariffs by region, and the network boundary is the regional boundary. On 17 September 2026 Octopus Flux paid 29.79p per kWh between 4pm and 7pm in the South Eastern region that covers Horsham town, against 29.00p in the Southern region that covers Billingshurst. The daytime rates were 10.24p and 10.08p, and the 2am to 5am rates 5.05p and 4.74p. The Outgoing Octopus tariff pays 12p in both.

The difference is small, but it is real, and it is a good test of any quote: an installer who knows the local network will get it right without being asked.

Generation, by contrast, barely changes across the district. PVGIS 5.3 puts a 4kW unshaded, south-facing array at about 4,231 kWh a year in Horsham and about 4,278 kWh in Billingshurst. Both are below the Sussex coast, where the same array in Worthing models at about 4,618 kWh.

If you are in the district and want to know what your roof could do, our page on solar panels Horsham covers local yields, prices and the connection process. We file the G98 or G99 paperwork with whichever operator serves your address.