We are not aware of GAAP standards requiring a certain level of documentation for payments. However, the IRS does require documentation to substantiate expenditures. The guideline is that the each transaction, such as an invoice or business expense receipt, provides enough information to document the economics of the transaction and what the expense was for. The IRS also states that you cannot deduct amounts that you approximate or estimate. T&E reimbursements would fall under this documentation. The IRS does not require receipts below $75 (though many companies internally require receipts for amounts over $25 or $50). In IRS Publication 463, (see pages 25-26) the IRS specifically states: "Documentary evidence ordinarily will be considered adequate if it shows the amount, date, place, and essential character of the expense...A restaurant receipt is enough to prove an expense for a business meal if it has all of the following information:
- The name and location of the restaurant.
- The number of people served.
- The date and amount of the expense."