The Government has issued new guidance on the NMW which can be found here: https://www.gov.uk/guidance/calculating-the-minimum-wage
The age bands and rates have been amended as follows:
23 years old + (National Living Wage) £8.91
21-22 years old £8.36
18-20 years old 3.56
Less than 18 £4.62
Apprentices £4.30