We do not go to market on a bill we have not read. Send the last three invoices. We check the volume, the meter type, and whether the last contract was a rush job.
Then we take the volume to the suppliers we hold — more than fifteen — and come back with a comparison you can actually read: term, product shape, standing charges, unit rates. A full tender is usually back in one to three days once we have the meter information.
Start as early as you can. We can tender up to 36 months before the current contract ends, so a rising market or a geopolitical shock is not a surprise on the bill. We keep a diary so cover does not lapse because someone was on leave.
You can walk away, stay short, or not switch at all.