Below is the UK's definitive guide to different premises usages in the UK. The government in 1987 decided to class different units with different usages, this is designed to give councils control to diversify streets, e.g. not just estate agents for takeaways etc.
In 2008 A3 was rebranded into 3 separate categories A3, A4 and A5 a business with the old A3 consent does not need to apply for A5 as they already have this permission in their current A3 Licence.
For full details on all planning issues please see the governments website for change of use
A1 Usage - Shops - Shops, retail warehouses, domestic hire shops, undertakers, hairdressers, travel and ticket agencies, pet shops, post offices, sandwich bars, showrooms, funeral directors internet cafes and dry cleaners.
A2 Usage - Financial and professional services - Financial services such as building societies and banks, professional services e.g. betting offices and employment and estate agencies.
A3 Usage - Restaurants and cafes - For the sale of drink and food for consumption on the premises - snack bars, cafes and restaurants.
A4 Usage - Drinking establishments - Wine bars or Public houses or other drinking establishments excluding night clubs.
A5 Usage - Hot food takeaways - For the sale of hot food for consumption off the premises.
B1 Usage - Business - Offices (other than those that fall within A2), development and research of processes and products, light industry appropriate in a residential area.
B2 Usage - General industrial - Use for industrial process other than one falling within class B1.
C1 Usage - Hotels - Guest Houses, Hotels, and boarding where no significant element of care is provided.
C2 Usage - Residential institutions - Residential nursing homes, hospitals, boarding schools, care homes, training centres and residential colleges.
C2A Usage - Secure Residential Institution - Use for a provision of secure residential accommodation, including use as a detention centre, custody centre, prison, secure training centre, young offenders institution, secure local authority accommodation, short term holding centre, secure hospital or use as a military barracks.
C3 Dwelling Houses
C3(a) Usage - covers use by a single person or a family (a couple whether married or not, a person related to one another with members of the family of one of the couple to be treated as members of the family of the other), an employer and certain domestic employees (such as an au pair, nanny, nurse, governess, servant, chauffeur, gardener, secretary and personal assistant), a carer and the person receiving the care and a foster parent and foster child.
C3(b) Usage - covers up to six people living together as a single household and receiving care e.g. supported housing schemes such as those for people with learning disabilities or mental health problems.
C3(c) Usage - allows for groups of people (up to six) living together as a single household. This allows for those groupings that do not fall within the C4 HMO definition, but which fell within the previous C3 use class, to be provided for i.e. a small religious community may fall into this section as could a homeowner who is living with a lodger.
C4 Usage - Houses in multiple occupation - Small shared houses occupied by between three and six unrelated individuals, as their only or main residence, who share basic amenities such as a kitchen or bathroom.
D1 Usage - Non-residential institutions - Clinics, day nurseries, crèches, day centres, health centres, places of worship, schools, museums, art galleries, libraries, halls, church halls, law court. Non residential education and training centres.
D2 Usage - Assembly and leisure - Cinemas, bingo, music and concert halls and dance halls excluding night clubs, skating rinks, swimming baths, gymnasiums or area for indoor or outdoor sports and recreations (except for motor sports, or where firearms are used).