Life insurance is available for diabetics but it can depend on the type of diabetes and how well the diabetes is controlled.
Some insurers are slightly less concerned with Type 1 diabetes compared to Type 2 and whether or not the diabetic in question is on tablets or insulin injections can also make a difference.

Insurance companies will consider a number of factors to asses a life insurance application for a diabetic and the most crucial is the HbA1C reading.
If the diabetes is well controlled the HbA1C reading should be between 6% and 8% (non diabetic levels are between 3.5% and 5.5%).
If the diabetes is well controlled then life insurance companies are usually happy to offer cover and in many cases this can be at competitive rates. Most life insurance companies are satisfied the control is good if the HbA1C reading is below 9.
Poorly controlled diabetes will attract a loading and the diabetic concerned will have to pay more for their life insurance. Some insurers will not offer cover with an HbA1C reading above 10.
In some cases if the HbA1C reading of a diabetic goes down and the diabetes is brought under good control, life insurance companies may reassess a policy and adjust the price accordingly.
As with any life insurance policy there are other factors which can affect the price such as height & weight, smoking & alchohol consumption and any history of illness.
Insurance companies choose to assess diabetes differently from one another so where one company may offer cover, another may not. It therefore makes sense to discuss options with a specialist who has experience of the market.