Whether you are looking to claim a deduction in your business or as an individual it is important to understand how the tax system works.
A tax deduction often feels like “free money,” but in reality it just reduces your taxable income — so the tax benefit is only a fraction of what you spend. Here’s a clear way to think about it:
What a Tax Deduction Actually Does
A tax deduction reduces the income the government taxes.
- Without a deduction:
You pay tax on your full income. - With a deduction:
You pay tax on a lower amount of income.
It does not give you back the full amount you spent.
Simple Example
Let’s say:
- Your income: $100,000
- Tax rate: 30%
- You claim a $10,000 deduction
Without deduction
- Taxable income = $100,000
- Tax = 30% of $100,000 = $30,000
With deduction
- Taxable income = $90,000
- Tax = 30% of $90,000 = $27,000
Result
- Tax saved = $3,000
- But you spent = $10,000
You are still $7,000 worse off in cash terms
The Core Principle
A deduction only saves you:
Your tax rate × the amount deducted
So:
- If your tax rate is 30% → you “get back” 30 cents per dollar spent
- If your tax rate is 45% → you get back 45 cents per dollar
You always spend more than you save.
Why You Usually Have to Spend Money
Most deductions exist because you incurred a cost related to:
- Earning income (e.g. work expenses)
- Running a business
- Investing (sometimes)
So to claim the deduction, you generally:
- Spend money
- Then reduce your taxable income by that amount
Real-World Examples
1. Work expenses
- You buy tools or training: $1,000
- Tax saved (30%): $300
- Net cost: $700
2. Business expenses
- Marketing spend: $20,000
- Tax saved (30%): $6,000
- Net cost: $14,000
The Key Insight (Very Important)
A deduction should never be the reason you spend money
Bad thinking:
“I’ll buy this because it’s tax deductible”
Better thinking:
“If I need to spend this anyway, the deduction softens the cost”
When Deductions Do Make Sense
They’re valuable when:
- The expense generates income (e.g. business investment)
- You needed it anyway
- It improves long-term financial outcomes (education, tools, etc.)
Deduction vs Tax Credit (Quick Contrast)
This helps clarify why deductions are limited:
- Deduction: reduces income → partial benefit
- Tax credit: directly reduces tax → full benefit
Example:
- $1,000 deduction → saves ~$300 (at 30%)
- $1,000 credit → saves $1,000
Bottom Line
- You almost always spend $1 to save less than $1
- The actual benefit = your marginal tax rate times the expense
- Deductions reduce pain, they don’t create profit
McNamara & Company - Chartered Accountants, located minutes from the Melbourne CBD
www.mcnamaraandco.au/contact-us
Phone +61 3 9428 1062
Email admin@mcnamaraandco.au
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