Green Belt is a policy, and land-use zone designation set out by Government and used in planning to retain areas of land and protect development that contributes to urban sprawl.
Unless you can demonstrate Very Special Circumstances then most development in Green Belt land is prohibited. There are some exceptions, mainly for agriculture and leisure, that apply. Green Belt is fixed and defined, you are either in it or you are out of it.
Greenfield is a term used to describe land that is previously underdeveloped, i.e. virgin land or agricultural land. Various definitions of greenfield exist so it is a woolier, more loosely used planning term. As greenfield sites are those considered to have potential for development they may typically (although not exclusively) be located at the edge of urban settlements. As 70% of land in the UK is designated for agricultural use this will make up the majority of greenfield in rural areas, with other land types including woodland or amenity spaces.
Although sounding similar, the implications and meaning of the two words are substantially different. If you are a landowner or Farmer wanting to develop in the Green Belt, it pays to have the strategy from the start.
The team at TRPC are well versed and experienced in dealing with planning in the Green Belt.