Who is responsible for unpaid utility bills, the renter or the tenant?
That would depend upon the rental agreement. It should be listed in the rental agreement who is responsible for the utility payments. If in the rental agreement states that the tenant is responsible then the tenant is responsible. If it states in the rental agreement the landlord is responsible, then the landlord is responsible. If it isnt in the rental agreement, then I would say that then it would be the responsibility of the landlord, but it could be different depending on the laws of the state or county the landlord and tenant reside in.