Mandatory entrance requirements to master's programs in British universities are:
For admission to the teaching and research programmes usually requires a bachelor's degree in the same or a related field, and CV, confirming the experience of scientific research and independent research work.
On most professionally-oriented programs having a professional experience is an entry requirement.
The level of requirements to the level of English depends on the subject area on which you do the General admission requirements of the University.
A number of programs primarily in the Humanities and social Sciences, also requires from students good writing skills texts and oral speech.