From 1 April 2015 the main rate of corporation tax applicable to larger companies is 20%. Historically, this was 30% and has been reducing over the last few years.
The small companies rate had been 21% and it also reduced to 20% a couple of years ago.
This means the UK now has one 20% rate of corporation tax for all companies no matter what their size.
This is one of the few examples of a rule simplification that also generates tax savings and is very much welcomed by us all… All for one tax rate and one tax rate for all.