Diabetes UK said more than 280,000 people a year are diagnosed with diabetes - the equivalent to the population of Newcastle.
Each day 738 people are told that they have type 2 diabetes - which is linked to being overweight- and 30 are diagnosed with type 1 diabetes - which is not linked to weight.
About 3.8 million people in the UK now have the condition and about 35 per cent of the population have borderline diabetes.
Diabetes UK has called for more focus on preventing type 2 diabetes, saying that if the rate of people getting the condition continues the consequences could be "disastrous".
The chief executive of the charity, Barbara Young, said: "It is deeply worrying that more than 700 people a day are being diagnosed with diabetes and this clearly shows the frightening scale of what is fast becoming a national health emergency.
"If we continue to see people being diagnosed at this rate then the consequences will be disastrous.
"As the number of people with diabetes grows, we are likely to see even more people endure devastating health complications such as amputation and kidney failure and more people die tragically young. It would also lead to an increase in NHS costs that would be simply unsustainable."