Sole trader reserve system

Build a tax reserve rule that works the moment a payment lands

Turn a realistic payment pattern into a simple reserve rule for tax, GST, and optional super. Start with the calculator, read the guides only if you need more context.

Reserve rule

7

dollars per 100 received

Use your own numbers →
Example

Where each dollar goes at 7-per-100

$4,500/monthly with $18,000 annual expenses, no HELP, no GST registration, private health insurance.

Component / 100 Annual
Income tax
7 $2,848
Medicare + MLS
1 $720
Business costs
33 $18,000
Owner pay
60 $32,432
Run with your own numbers →
Guides

Read only the context you actually need

Use the calculator first. These guides answer the questions that come right after the reserve rule is set.

Next steps

Move from reserve rule to the next tool in the workflow

After the reserve rule, the next job is usually BAS detail, annual modelling, or due dates.

Task routes

Choose the next tool by the decision you are making

Use one of these short routes if the reserve rule is clear but the next operational question still is not.

FAQ

Questions this tool is designed to answer quickly

How much tax should a sole trader set aside in Australia?

There is no single percentage that fits every sole trader. The right reserve rule depends on annual profit, GST registration, HELP debt, Medicare settings, and whether you also want to set money aside for super.

Should I separate GST from income tax?

Yes. GST is not your income. If you are GST registered, treat GST collected as a separate bucket and only rely on the net amount after eligible GST credits from creditable business purchases.

Does this tool replace advice from an accountant or BAS agent?

No. It is an informational planning tool built to simplify set-aside decisions. You should confirm your exact tax, GST, and reporting obligations with a registered tax professional.

Is this a bookkeeping system?

No. It is a reserve-rule app. The point is to create a simple habit for each typical payment pattern, not a full ledger.

Why show dollars per 100 received?

A ratio is easier to apply in real life than a yearly estimate when money hits the account.

Will super always reduce the tax estimate?

No. The calculator only treats personal super as deductible when you choose that setting, and the estimate assumes you will meet the ATO deduction conditions.

Can I share a setup with my accountant?

Yes. The calculator stores state in the URL so the same assumptions can be shared directly.


Last updated 13 March 2026 Tax year 2025-26

Data sources: ATO (ato.gov.au), Services Australia

This tool is general information only, not financial advice.

Reviewed by AusTax Tools Editorial Desk

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