Business Expense Categorisation Calculator

Why categorising business expenses matters

Business expense categorisation is the process of sorting every cost your business incurs into defined groups. It is a fundamental part of bookkeeping, tax preparation, and financial management. Without clear categorisation, it is almost impossible to understand where your money is going, whether your spending is aligned with your priorities, or where you might cut costs without harming revenue.

This calculator gives you an immediate visual breakdown of your monthly expenses by category, sorted by size. Seeing which categories take the largest share of spending is often revealing. Many business owners are surprised to discover that payroll costs represent 60 to 70 percent of total expenses, or that marketing spending is a much smaller proportion than they assumed. This clarity is the starting point for cost control decisions.

Consistent categorisation also makes tax preparation much simpler. Different expense categories may be treated differently for tax purposes. COGS is deducted as a direct business expense. Professional fees, marketing, and technology costs are typically deductible operating expenses. Rent and utilities are deductible. Some categories have specific rules or limits. Keeping categories consistent throughout the year ensures you can produce the right reports quickly at tax time.

Standard business expense categories

While every business is different, most accounting systems use a similar set of categories: cost of goods sold (direct costs of products or services delivered), payroll and wages, rent and facilities, marketing and advertising, technology and software, professional services (accountants, lawyers, consultants), travel and transport, utilities, insurance, and a catch-all "other" category. Some businesses add equipment depreciation, R&D, and customer service as separate categories.

How should I handle mixed personal and business expenses?

If an expense is used partly for business and partly for personal purposes (a home office, a vehicle, a phone), only the business-use proportion is deductible. Track the business portion and record it accurately. For vehicles, a mileage log is the most defensible record. For home offices, the square footage proportion is the standard method. Never mix personal and business expenses in the same account.

What is the difference between fixed and variable expenses?

Fixed expenses do not change with your revenue or output: rent, insurance, software subscriptions, and base payroll are typically fixed or semi-fixed. Variable expenses move with activity: cost of goods sold, sales commissions, shipping, and hourly labour scale up and down. Understanding which of your expenses are fixed versus variable helps you model how costs will change as your business grows or shrinks, and identifies where you have the most flexibility during a downturn.

How often should I review my expense categorisation?

Monthly is the right cadence for most businesses. A monthly review catches mis-categorised transactions quickly before they pile up into a year-end nightmare. It also gives you 12 comparable data points per year, making it easy to spot trends, seasonal patterns, and unexpected cost increases early enough to act on them.