0842 numbers are categorized as "Special Services: Basic Rate" numbers.
They are not currently in operation and are reserved for future use.
They are in the same category as 0844 and 0843 numbers, so won't be included in free call bundles from telecoms providers, unlike 0845 numbers.
Numbers in this category are typically used by businesses for sales, enquiry and customer service lines. They are also sometimes used for pay-per-minute internet services.
The cost of calling 0842 numbers will be in line with those of 0844 and 0843 numbers: currently up to 13p per minute from a land line, and up to 41p per minute from a mobile phone. The calling cost varies with the telecoms provider and the individual number.
0842 numbers cannot be described as 'local rate' numbers, and the Advertising Standards Authority can take action against companies that describe them as such.