how much can you write off a car for business

Short answer: you can only write off the business-use portion of a car, not the Sunday Bunnings run. The purchase price is capital, claimed via depreciation; if it’s a ‘car’ under ATO rules (under 1‑tonne payload or <9 seats), a car limit caps the amount you can depreciate. Many utes and vans with >1‑tonne payload aren’t ‘cars’, so that cap may not apply, but you still only claim the business-use percentage.

Small businesses may be able to use the instant asset write‑off for eligible vehicles and tools up to a set threshold, but the threshold and dates change often. Running costs—fuel, servicing, insurance, rego, interest—are generally deductible to your business‑use %, and GST credits are usually limited the same way. Keep a 12‑week logbook (or solid trip records) and talk to your accountant, because the ATO loves detail almost as much as you love parking near the kerb.