Ordinary and Necessary

• To deduct office supplies or other business expenses, the expenses must be both ordinary and necessary for your business or profession. A necessary expense is something that will help the business, even if that expense is not a critical need, and an ordinary expense is one that's common for the type of business you operate or for the profession you are in.
  
  

Business Expenses

• Business expenses are items and activities that are needed for the business to carry on and continue operating. Office supplies such as printer paper, pens and pencils, staplers, binders, tape and file folders are generally considered both ordinary and necessary for all businesses; as a valid business expense, they are tax deductible.
  
  

Capital Expenses

• Capital expenses are part of the investment you make in your company. They can include business assets, startup costs and improvements. Office furniture is an example of a capital expense. Since the furniture is an asset and investment in your company, it is more than just general office supplies and cannot be deducted as an office supply expense.
  
  

Cost of Goods Sold

• The cost of goods sold can sometimes be confused with office supply expenses for certain types of businesses. If, for example, you purchase a pallet of printer paper and resell it for a profit, the costs of the printer paper are costs of goods sold.