Monthly utility costs include separate charges for electricity, gas, water, sewer and trash. If you choose to add Internet and cable, this will be an additional charge you will want to budget for. Average monthly utility bills can vary based on two factors: the square footage breakdown of your apartment and the number of people who live in your apartment. Additionally, your costs will depend on how much you use your appliances and the amount of time you spend in your apartment home. Monthly costs can range from $50 - $100 for electricity, $20 -$35 for gas, $50 - $100 for water, trash and sewer, and $80 - $120 for Internet, cable and streaming services. Utilities may also vary by location. For example, your monthly gas charges may be less in Northern California, but higher in the Seattle Metro area where winters can be more intense.