Office Expenses are costs related to the operation of your business. These include items such as web site services, computer software, domain names, merchant fees, desktop computers, office phone systems, employee cellphones, etc. However, higher priced office expenses, e.g. computers, smartphones, are considered assets and can be depreciated.
Office supplies are items that aid in the short-term operation of your business. These items usually need to be refilled or replaced. These include items such as printer ink, paper clips, paper, pens, staples, record keeping supplies, janitorial supplies, break room supplies, etc.