The general rule
South African tax law lets you deduct expenses incurred in the production of income that are not of a capital nature. In plain terms: costs you genuinely incur to run and grow the business, as opposed to buying long-lived assets (those get treated differently, through wear-and-tear allowances). Get comfortable with that test and most questions answer themselves.
The everyday deductions
The bread and butter: rent, salaries and wages, stock and materials, bank charges, accounting and legal fees, insurance, marketing and advertising, business travel, phone and internet, software subscriptions, and repairs to business equipment. If it's a real cost of doing business and you can prove it, it generally comes off your taxable income.
Home office — allowed, with conditions
If you genuinely work from a dedicated home office, you can claim a proportion of your home running costs — rent or bond interest, rates, electricity — based on the floor area used exclusively for business. SARS is strict here: the space must be regularly and exclusively used for work and specifically equipped for it. Claimed properly it's valuable; claimed loosely it's an audit magnet.
Vehicles and travel
Business travel is deductible, but private use isn't — so the rules hinge on records. Keep a logbook distinguishing business from private kilometres; without one, SARS can disallow the claim entirely. This is the single most common area where good intentions meet bad record-keeping.
Wear-and-tear (capital assets)
You can't deduct the full cost of a laptop, machine or vehicle in one year — instead you claim wear-and-tear allowances that write the asset off over its useful life (Small Business Corporations get accelerated write-offs, sometimes 100% in year one for certain assets). It's still a deduction; it's just spread differently.
What you can't claim
Private and domestic expenses, fines and penalties, the capital portion of loan repayments, and entertainment that's really personal. The line between a genuine business cost and a personal one dressed up as business is exactly where SARS focuses on audit — and where an accountant earns their fee by keeping you on the right side of it.
The thing that makes it all work: records
Every deduction stands or falls on evidence. Valid tax invoices, a clean separation of business and personal spending (a dedicated business bank account is non-negotiable), and current bookkeeping turn "I think I spent that" into a defensible claim. Deductions aren't found at year-end — they're captured all year. That's what our bookkeeping does.