The following are some commonly encountered items that usually will not be allowed as a business expense deduction. In most cases, a deduction is denied for these items either because they are nondeductible personal expenditures, or because Congress specifically made them nondeductible.
Nondeductible Business Expenses
bar or professional examination fees
capital expenditures (not fully deductible in the year placed in service, but yearly deductions are allowed to recover the cost of the item over a specified time period)
charitable contributions or gifts by a business that is not a C corporation (sole proprietors may deduct contributions on their individual tax returns, rather than on Schedule C).
clothing, unless it's protective equipment, or a uniform that would not be worn during non-working hours
country club, social club, or athletic club dues
estate taxes, even if largely due to the ownership of a business interest
expenses, including interest, paid to generate tax-exempt income
federal income tax
fines and penalties incurred for violations of law, such as child labor violations, federal income tax penalties, traffic tickets.
gift tax; inheritance tax
gifts to employees that are valued at more than $25
any portion of a gift to a business contact that is valued at more than $25
interest on indebtedness incurred by a business taxpayer to purchase life insurance coverage in excess of $50,000 on the life of any its officers, employees, or other person having a financial interest in the taxpayer's trade or business
interest on indebtedness incurred to purchase single premium life insurance contracts, or any life insurance contract under a plan of financing the purchase by withdrawing some or all of the yearly build-up in policy cash values
job hunting expenses (for a new trade)
life insurance premiums, if the business, or the business owner, is a direct or indirect beneficiary.
lobbying expenses (appearances before legislative bodies and expenses to influence voters)
partnership organizational expenses, unless amortization election made
personal, living, or family expenses; however, certain interest, taxes, bad debts, medical expenses, theft or casualty losses, or charitable contributions may be deductible in whole or in part as an itemized deduction on your individual tax return