Common Business Expenses are all the costs incurred to run a business. This includes everything from advertising and marketing services to employee salaries, rent or mortgage payments, taxes, utilities, insurance and other miscellaneous costs. Understanding these expenses will help you properly report them on your tax returns so you can maximize deductions. Every business should keep detailed records of these expenses in order to accurately track and organize finances. Additionally, paying close attention to these expenses can greatly increase the efficiency of your business operations.