Send a letter to your energy supplier online
Billing disputes, complaints about a smart meter, deemed contract queries or a formal complaint before going to the Energy Ombudsman - write it here and we'll post it the same working day.
Energy suppliers are required by Ofgem rules to acknowledge a formal complaint and give you a final response, or a deadlock letter, within 8 weeks. A written complaint by post is the clearest way to start that clock, and it's the piece of evidence the Energy Ombudsman will ask for if your supplier doesn't sort things out.