There will be consultation on listing generally in the government's forthcoming Heritage Green Paper.
The 13 commercial, three industrial and five railway buildings added to the list of buildings of special architectural or historic interest are spread across the country.
They also include New Street Signal Box, Birmingham; the Rhone Poulenc canteen in Dagenham; the Heinz headquarters building in Hillingdon; the Sheldon Bush Shot Tower in Bristol; and the CIS Building in Manchester.
National heritage secretary Virginia Bottomley said: 'The best of modern buildings should be listed to protect them from unsympathetic development and preserve them for future generations.
'We have considered carefully all the evidence, including English Heritage's advice and representations from owners and others. We are satisfied that the 21 buildings listed today are among the best of their kind and are individually of special architectural or historic interest.'
'For the first time we gave owners and the general public the chance to comment on listing recommendations and received more than 2000 responses. In reaching our decisions we were able to take account of a wide range of informed comment.
'The deep interest of the public - from passers by to local authorities and architectural experts - in our most important buildings has been demonstrated by the response to this consultation.
'Although all the buildings recommended by English Heritage which we have declined to list are of high quality, we were not satisfied that they individually possessed those special qualities we must look for when making decisions.
'I hope that there will be further public discussion of the principles, extent and future of the listing process when we publish a Green Paper early in the New Year.'