Under the blight provisions of the Town and Country Planning Act, owner occupiers of premises which are the subject of compulsory purchase powers or other development proposals may serve a blight notice on the acquiring authority. Service of a blight notice which is not countered by the authority takes effect as a deemed notice to treat. This means that the authority can be compelled to acquire the property and/or pay compensation, whether or not the CPO or development proposal proceeds. The owner must have attempted to sell the premises, and those attempts have either failed, or a sale could only have been achieved at a substantially reduced price.

In order to serve a blight notice, the premises must be below a rateable value threshold. Currently this is £29,200 but as from 1 April, the threshold is increased to £34,800.