What is a tax deduction? Definition, types and how to claim

Published Thursday 23 July 2026

Table of contents

• Tax deductions definition
• Example of a tax deduction calculation
• Types of tax deductions for small business
• What you can't claim as a tax deduction
• How to claim tax deductions
• Record keeping requirements
• Common tax deduction mistakes to avoid
• Simplify your tax deductions with Xero
• FAQs on tax deductions

Key takeaways

• A tax deduction is a business expense that reduces your taxable income, meaning you pay less tax overall. Common deductible expenses include office costs, business travel, professional services and marketing.
• You need to keep detailed records of all business expenses for 5 years, including receipts, invoices and documentation that proves the business purpose of each expense.
• If an expense is used for both personal and business purposes, you can only claim the business portion. For example, if you use your phone 80% for work, you can deduct 80% of the cost.
• Using accounting software to capture and categorise expenses as they happen makes it easier to track every eligible deduction and simplifies the process at tax time.

Understanding tax deductions can help you reduce your tax bill and keep more of the money your business earns. Here's what tax deductions are and how they work.

Tax deductions definition

A tax deduction is a business expense that reduces your taxable income, so you pay less tax. Tax deductions work by subtracting eligible expenses from your gross income to arrive at your taxable income.

Common deductible expenses for small businesses include:

• Office expenses: rent, utilities, equipment and supplies
• Business travel: transport, accommodation and meal costs
• Professional services: insurance, legal fees and accounting costs
• Marketing costs: advertising, website expenses and promotional materials

The Australian Taxation Office (ATO) sets the rules for which expenses you can claim and when. Always check the ATO website for the latest guidance on eligible deductions.

Getting the numbers right starts with understanding how deductions affect your tax. The next section walks through a real-world example.

Example of a tax deduction calculation

Tax deductions reduce your taxable income by subtracting legitimate business expenses from your total income. Here's how it works in practice.

Jo owns a photographic studio and earned $77,000 last year. She has $15,000 in deductible business expenses, which reduces her taxable income to $62,000.

$77,000 (gross income) - $15,000 (deductions) = $62,000 (taxable income)

Jo pays tax only on $62,000, not her full $77,000 income, so she saves money on tax.

Business purpose requirement

For an expense to qualify as a tax deduction, it must have a legitimate business purpose. A camera is deductible for a photographer, but not for a baker.

Personal vs business expenses

Not every expense you pay is fully deductible. You need to separate personal and business costs.

• Personal expenses: cannot be deducted (groceries, personal clothing).
• Mixed-use expenses: claim only the business portion (80% business use = 80% deduction).
• Purely business expenses: fully deductible when used exclusively for work.

Record keeping essentials

Keep receipts for all expenses you plan to deduct. Proper documentation protects you during an ATO audit and makes sure you can claim legitimate deductions.

Now that you understand how deductions are calculated, here are the specific types of expenses you can claim.

Types of tax deductions for small business

Australian small businesses can claim a range of deductions. Check the latest guidance from the ATO or speak with an adviser to make sure you claim the right expenses.

Work-related expenses

These are costs you incur to earn your income. They can include vehicle and travel expenses, self-education related to your work, and clothing and laundry for uniforms. In 2023-24, Australians claimed a combined $27.6 billion in work-related expenses, with car expenses ($10.3 billion) making up the largest category. Clothing deductions are only available in limited circumstances and must fit into specific categories.

Business operating costs

These are the day-to-day running costs of your business. They include items like rent for your office, staff salaries and office supplies. Some expenses may also qualify for the instant asset write-off, which allows eligible small businesses to immediately deduct the cost of eligible assets. Check the ATO website for current thresholds and eligibility.

Home office deductions

If you work from home, you may be able to claim a portion of your household running expenses. Around 4 million Australians claimed working-from-home expenses in 2023-24.

Using the ATO's fixed rate method, you can claim 67 cents for each hour you work from home. This covers costs like electricity, phone, internet, and the decline in value of office furniture. Alternatively, the actual cost method lets you calculate the specific costs of running your home office, which may result in a higher deduction if your expenses are significant.

Vehicle and travel expenses

If you use your vehicle for business purposes, you can claim the cost of those trips. The ATO offers 2 methods for calculating car expense deductions.

• Cents per kilometre method: claim a set rate per business kilometre (currently $0.88 per km for 2024-25), up to a maximum of 5,000 business kilometres per year.
• Logbook method: keep a logbook for at least 12 continuous weeks to establish the business-use percentage of your car, then claim that percentage of your actual running costs.

Business travel expenses like flights, accommodation and meals for work trips are also deductible, as long as the primary purpose of the trip is business-related.

Self-education expenses

You can claim self-education expenses if the course or training directly relates to your current work. The education must maintain or improve a specific skill or knowledge required in your current role.

Eligible costs include course fees, textbooks, stationery, student union fees and travel to attend classes. You can't claim self-education expenses for a course that helps you get a new job or move into a different occupation.

Depreciation and asset write-offs

When you buy assets for your business, such as equipment, tools or vehicles, you can claim their cost over time through depreciation. The ATO's instant asset write-off allows eligible small businesses to immediately deduct the full cost of eligible assets up to a set threshold, rather than claiming depreciation over several years.

Check the ATO website for the current threshold amount and eligibility criteria, as these can change each financial year.

Knowing what you can claim is only half the picture. It's equally useful to understand what you can't deduct.

What you can't claim as a tax deduction

Some expenses are never deductible, no matter how closely they seem connected to your business. Being clear on what falls outside the rules helps you avoid penalties and wasted time at tax time.

Expenses you can't claim include:

• Personal expenses: groceries, personal clothing, gym memberships and other costs unrelated to earning your income.
• Fines and penalties: traffic fines, parking tickets and ATO penalties are not deductible, even if they were incurred during work.
• Entertainment: the cost of entertaining clients or staff at restaurants, sporting events or social functions is generally not deductible.
• Capital expenses: costs related to buying or improving a long-term asset (like renovating your office building) are not immediately deductible, though they may be claimed through depreciation over time.
• Private portion of mixed expenses: if an expense is partly personal and partly business, only the business portion is deductible.

If you're unsure whether a specific expense qualifies, check the ATO website or speak with a registered tax agent.

Once you know which expenses qualify, the next step is understanding how to claim them correctly.

How to claim tax deductions

Claiming deductions doesn't have to be complicated. It comes down to following a clear process and keeping good records throughout the year.

Follow these steps to claim your deductions:

1. Confirm you spent the money yourself and weren't reimbursed.
2. Make sure the expense directly relates to earning your income.
3. Keep a record (like a receipt) to prove the expense.
4. Calculate the deductible amount, separating any personal use.
5. Enter each deduction in your tax return under the correct category.

Using accounting software to track deductions

Tracking expenses manually can lead to missed deductions and errors. Using accounting software helps you capture and categorise expenses as they happen, so you can claim all your eligible deductions at tax time.

Good records are the foundation of every successful deduction claim. Here's what the ATO expects you to keep.

Record keeping requirements

The ATO requires you to keep records that prove your income and expenses. Good records make tax time smoother and protect you in case of an audit.

What records to maintain

You should keep records for all your business transactions. This includes invoices, receipts, bank statements and contracts.

For expenses, your records should show:

• What you bought
• When and where you bought it
• How much you paid
• How it relates to your business

How long to keep records

You need to keep your business records for 5 years from the date you lodge your tax return. The ATO requires you to keep your written evidence for this period, so make sure your filing system is organised and accessible.

Digital vs physical records

You can keep records in paper or digital format. Digital records are easier to store, search and back up. Use software to snap photos of receipts and reduce paper clutter.

Even with the right records in place, there are common pitfalls that can trip you up. Here's what to watch out for.

Common tax deduction mistakes to avoid

Knowing about common mistakes can help you claim with confidence at tax time.

Personal vs business expense confusion

You can only claim the business-use portion of an expense. If you use your car for both business and private trips, you need to separate the costs and only claim the business part.

Insufficient documentation

You can't claim a deduction if you don't have a record to prove it. Make sure you keep clear, organised records for every claim, and store them securely for at least 5 years.

Overclaiming risks

If you claim something you're not entitled to, you may face penalties. Over-claimed deductions are one of the key drivers of Australia's small business income tax gap, which the ATO estimates reached $27.2 billion in 2022-23. If you're unsure whether an expense is deductible, check the ATO website or ask an accountant or bookkeeper.

Staying on top of your deductions throughout the year is easier with the right tools. Here's how Xero can help.

Simplify your tax deductions with Xero

Tracking every receipt and categorising every expense throughout the year can feel like a big job. Xero accounting software automates the process by connecting to your bank feeds, matching transactions and organising your expenses in real time.

With Xero, you can snap photos of receipts using Hubdoc, categorise expenses as they happen and generate reports that make tax time straightforward. Your accountant or bookkeeper can access your data directly, so there's no back-and-forth at the end of the financial year. Get one month free.

Here are answers to some frequently asked questions about tax deductions.

FAQs on tax deductions

Can you claim a $300 tax deduction without receipts?

For work-related expenses, you can claim up to $300 without receipts. According to the ATO, if your total claim for work-related expenses is $300 or less, you don't need full written evidence, but you must still be able to show how you calculated the claim.

What's the difference between a tax deduction and a tax offset?

A tax deduction reduces your taxable income before tax is calculated. A tax offset (also called a tax credit) directly reduces the amount of tax you owe, which usually results in a larger saving dollar for dollar.

Can I claim personal expenses as business deductions?

You can only claim the business portion of an expense. If an expense is partly personal, you need to calculate and claim only the percentage used for business purposes.

Is income protection insurance tax deductible?

Premiums for income protection insurance are generally tax deductible if the policy pays a regular income stream when you can't work due to illness or injury. Lump sum policies don't qualify for the same deduction.

Are superannuation contributions tax deductible?

Personal superannuation contributions may be tax deductible if you lodge a notice of intent with your super fund and receive an acknowledgement before lodging your tax return. The concessional contributions cap applies, so check the current limit on the ATO website.

How do I know if an expense is tax deductible?

An expense is generally deductible if it directly relates to earning your income and you have a record to prove it. The ATO provides detailed guides for different industries, and a registered tax agent can give you advice specific to your situation.