Over 2,400 homes have benefited from Council Tax discounts on family annexes or 'granny flats'.
More than £1.3 million has been knocked off bills nationwide since the charge was reduced last year. Before the change two Council Tax bills were being levied on the same home if it had a 'granny flat' or similar extension.
Discounts of 50% were granted for properties where families were housing non-dependent relatives, in addition to existing exemptions given to families who were housing a dependent relative.
Nearly 17,000 households are now getting a discount or exemption.
According to Government figures, Cornwall is the granny flat capital of England with 595 households receiving support.
The top 10 looks like this:
Number of exempt annexes: Class T
Number of exempt annexes: Class W
Estimated number of dwellings that received a family annex discount
Total annexes getting support
King's Lynn and West Norfolk
Number of exempt annexes is the number of dwellings in Class T and W exemptions on the October 2014 Council Tax Base form
Class T applies to annexes which may not be let separately from the main property because of a planning restriction
Class W is the dependent relative exemption
Ministers believe that many more people are entitled to the reductions and they're urging town halls to be more forthcoming with residents who are likely to benefit from the scheme.
If you think you might be entitled to this Council Tax cut, make sure you contact your local council. You should get back any Council Tax you have overpaid dating back to last year.
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