Unfortunately, depending on the amount of utilities, a verbal agreement may not be binding based on the statute of limitations. If two families live under the same roof (not clear from your question), then whomever is on the utility is the responsible party and whatever separate agreement you have verbally may not be binding if you haven't performed on it yet. I assume since there is a threat of shutting off utilities to the second party, this is either a duplex or similar living situation. If so, consider getting the utilities placed in your name. Simply contact the utility company, explain what is happening and have them come out and see if it can be done. If the other party owns the duplex, the utility company and the agency that handles landlord tenant matters may both have to get involved.