Miscellaneous expenses are defined by the IRS as any write off that doesn't fit into one of their tax categories. Small business owners can claim these expenses to reduce their taxable income. Miscellaneous expenses must be itemized in your taxes; you can't take the standard deduction for them.

In both business and travel accounting, miscellaneous (or "misc") expenses are small, irregular, or non-recurring costs that do not neatly fit into major established categories like "Lodging," "Airfare," or "Meals." These are often "one-off" purchases that are too minor to justify creating a dedicated line item in a budget. Common examples during travel include tipping (to porters or housekeeping), small administrative fees like ATM surcharges, laundry services, or emergency purchases like a replacement charging cable or an umbrella. In a business context, it might include a small "thank you" gift for a client or a one-time postage fee. While individual miscellaneous expenses are small, they can add up significantly over a long trip. Most companies have a "de minimis" rule where small expenses under $25–$75 do not require a formal receipt for reimbursement, though it is always best practice to keep a log. Accountants generally advise keeping "miscellaneous" to less than 5% of a total budget to ensure financial transparency and to avoid triggering red flags during a tax or corporate audit.