Simply put, drying clothes on a radiator can lead to increased bills over time. Essentially, the use of radiators or heated towel rails to dry clothes will force your boiler to work harder than it would otherwise need to, in turn causing running costs to increase.
There are also health risks attached to drying clothes on a radiator, plus concerns about potential damage it could cause to the surface of your heating device, therefore it is not recommended to dry clothes on a radiator.
To find out more details, take a look at our blog, Should I dry my clothes on a radiator?