Members of visiting forces and certain international institutions
Where an adult isn't counted for council tax, any person in the household can apply for the 25% discount.
For example: one student living with one adult who pays council tax
As the student, you can apply for the 25% discount for this household as there is only one adult who should pay council tax for that property. Alternatively, the adult who should pay council tax, could apply for this discount.
Please note, a full exemption would apply where all adults living in the property are not counted for council tax. For example, three students living together.