Allowable business expenses are those costs that a company incurs as part of its operations which have been deemed to be “reasonable and necessary” by the Internal Revenue Service (IRS). These costs may include items such as materials, travel, office supplies, and equipment rental. Expenses must be documented with receipts or other proof of purchase in order to be eligible for deduction from the company’s taxable income. It is important for companies to remember that although certain expenses may help them gain an advantage against their competitors, not all expenses are actually allowable under tax law. Keeping accurate records of all expenses is key to ensuring that only eligible expenses are claimed.