The inflation rate was up from the 4.7 per cent figure in June.
The increase was driven largely by higher food prices over the past year. They were 9.1 per cent higher in July 2008 than in the same month last year.
In May 2008, annual inflation stood at 5.4 per cent.
Monthly inflation increased by 0.2 per cent between June and July this year as transport costs grew by 5.6 per cent. However, food prices were down slightly by 0.1 per cent over the month, despite having risen so sharply over the past year.