All self-employed people, including contractors and sole traders, can claim expenses against their income.

Brian from Mount Roskill

What you can claim for
Business expenses can include:
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vehicle expenses, transport costs and travel for business purposes
rent paid on business premises
depreciation on items like computers and office furniture
interest on borrowing money for the business
some insurance premiums
work-related journals and magazines
membership of professional associations
home office expenses
work-related mobile phones and phone bills
stationery
work uniforms
tax agent’s fees.
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If you own an investment property, expenses you can claim for include:
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repairs and maintenance (but not renovations that substantially improve the value of the property)
professional services fees, like accountants, lawyers or property managers
rates and insurance
mortgage repayment insurance
vehicle and travel expenses when you travel to inspect your property or do repairs
depreciation on capital expenses, like whiteware, appliances or heat pumps
legal fees involved in buying a rental property, as long as the expense is $10,000 or less.
How much can you claim?
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You can't claim the whole cost of all items, even those only for business use. Some things you can only claim half for, eg some entertainment expenses. You can only claim 100% of the cost for an expense that’s entirely for business use.
If you have an expense that’s partly for your business and partly for your private use, you can claim the proportion that relates to your business.
Example:
If you spend half the time driving a vehicle to deliver goods and the other half for your own reasons, you can claim 50% of the travel costs for your business.
For some expenses, like business entertainment, eg client meals and staff functions, you can only claim half.
Working from home
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If you use an area of your home for your business, eg your study or garage, you can claim a portion of the household expenses, eg:
rates
power
house and contents insurance
mortgage interest if you own the home
rent if you are renting the home.
You must keep invoices for these expenses.
How it works
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If your home is 100 square metres and your working space is 10 square metres — 10% of the total area — you can claim 10% of expenses that are not solely for your business, eg your home phone line.
If you aren't using a separate area of your home for business, you'll need to take into account how much time you spend on your business and the area used.
If you're GST registered, the GST content on home office expenses can be claimed as they’re paid — in each GST return period — or at the end of your tax year. Mortgage interest and rent don’t include GST.
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