I just bought a single family home that fits 5 people, it is close to a university so I am renting each room seperately to students generally. I have in my contract that utilities are the tenants responsibility.  However, one of the students left early for the summer. He has been great and paid for rent for the rest of the contract (about a month and a half), but apparently is not paying his share of utilities. The tenant in charge of the utilities contacted me and wants me to withhold security deposit money to pay for the other student's portion.  Keep in mind, none of the tenants knew each other before they moved in, and I had designated his room as the tenant to be in charge of utilities, so he didn't choose his position as being in charge of utilities.  I feel like it is a bit unfair for him to be saddled with the other person's utility portion, but I also don't know if I am able to or unable to withhold security money.  It seems like if the contract says it's the tenants responsibility to pay utilities, then it is almost like a rent money and can be withheld from security deposit. 

Going forward I want to make some sort of clause where it is super clear what happens in this kind of a situation. But I am not quite sure what the best way to move forward is. I also, really would like to not have to do this sort of thing in the future and just make sure I am getting rent money.  If I don't withhold security deposit money for tenant's who don't pay utilities, then should I move forward with kicking them out because they are not paying their share? What is the best way to do utilities when you have individual contracts with each person, but it is still all of their responsibility to pay it?