In order to get exemption from payment of council tax, students need to be studying full-time.
Do not assume just because you are students that there will automatically be no charge made for council tax during your tenancy. You will need to supply Oxford City Council with proof of your student status. The administration office at your college will be able to provide you with a "student status" letter which will confirm your college and the dates of your course. This letter needs to be scanned and sent to firstname.lastname@example.org with your property address.
The council will issue you an exemption certificate for your property. It is important to retain this certificate and advisable to let your landlord or letting agency have a copy too.