You can get non-domestic rates relief through the Small Business Bonus Scheme if:
the combined rateable value of all your business premises is £35,000 or less
and, the rateable value of individual premises is £18,000 or less
From 1 April 2020 SBBS relief will only be available for properties that are actively occupied.
It's free to apply for rates relief, including the Small Business Bonus Scheme. You should be wary of anyone who proposes to apply on your behalf for a fee. Please read more here.