Business Expense Report Categories are essential in helping businesses keep track of their finances. These categories serve to divide expenses into logical areas and ensure that all related costs can be accounted for accurately. Common categories include travel, training, materials and supplies, overhead, insurance and payroll. Each category can be further broken down into more specific types of costs. Businesses should keep track of these expenses as they will help them monitor their spending and make informed decisions about their budget. Knowing which expenses are necessary and how much is being spent on each helps to create a healthy financial system.