You’ll need to contact the Valuation Office Agency to appeal against your Council Tax band.
The banding is determined by the Valuation Office Agency.
This band is determined by the value of your property (this value is the amount for which the property would have been expected to sell for on the open market on 1 April 1991). The table below shows the values for each band:
You can check the banding of any property by visiting the Valuation Office Agency website at www.voa.gov.uk