In the UK, a Master's in Computer Science degree usually takes one year of full-time study to complete. Some universities may offer a part-time option, which would take longer to complete, typically two years. However, the duration of the program can vary depending on the institution, the specific program, and the mode of study (full-time, part-time, or online). It's important to check the program details for the specific university you're interested in attending to determine the exact length of time required to complete the degree.