Find my block letter

Block letters help the electricity networks identify which part of the electricity grid your home is connected to.

Your home and street are connected to the electricity network through a substation. This connection is given a code known as a ‘Block Letter’. You can find this on the first page of your energy bill or by entering your postcode on our website.

The country is divided into many block letters. In the unlikely event that a power cut rota is introduced in an energy shortage, most people in the same block letter will be timetabled to be without power at the same time.

Your Block letter won’t change unless you move home. It’s based on where you live and how your property is connected to the electricity network.

You can find your Block Letter:

  • By entering your postcode on our site

  • By looking for the letter at the top of your energy bill. It usually appears near the supply address and will be a single letter in a box. Depending on who supplies your energy, it might be labelled ‘Rota Block Letter’ or it may not have a label.

If you cannot find your Block Letter from either this website or your electricity bill, call 105 for free to speak your local network operator.

Learn more about energy shortages.