When it comes to running a business, knowing the difference between office supplies and office expenses is key. Office supplies are items that you purchase to help you do your job, such as computers and other electronics, pens and paper, desk organizers, etc. On the other hand, office expenses refer to costs related to keeping the office functioning, such as rent or lease payments, utility bills, insurance premiums, etc. In short, office supplies are used to complete your work while office expenses keep the office operational. Put simply: supplies ‘do’ while expenses ‘pay’.