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🦎 Elite Tools #2: Iggy IRAS Relief Optimizer (YA 2026)

Stack Your Tax Reliefs. See What IRAS Doesn't Show You.

The Investing Iguana's avatar
The Investing Iguana
Mar 25, 2026
∙ Paid

The full forensic breakdown of how these reliefs stack is in the explainer article — this post is where the tool lives.


Mr. Lim is fifty-six, earns S$195,800, and was staring at a S$20,394 tax bill.

After running his numbers through the Iggy IRAS Relief Optimizer, his chargeable income dropped to S$90,800. His tax bill dropped to S$4,592. The difference—S$15,802—came entirely from reliefs the tax code already allowed him.

He did not do anything differently. The forensic audit just read the receipt correctly.

The tool does the same for your numbers. Four income scenarios, modelled in parallel, in under two minutes.

Members: tool access and usage guide below.

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How to Use the Iggy IRAS Relief Optimizer

The tool opens in a new tab via Google AI Studio. A Google account sign-in is required to access the interface, but no personal data is collected or stored — your inputs exist only in your session and are not saved anywhere.

Step 1 — Enter your income

Input your gross employment income, net rental income (gross rental minus allowable expenses such as mortgage interest, property tax, maintenance, and agent fees), and any other assessable income. Leave SGX dividends out — Singapore does not tax dividends and they do not appear in your IRAS assessment.

Step 2 — Enter your current reliefs

Tell the tool what you are already claiming: SRS contributions made to date, CPF cash top-up amounts, number of qualifying parents and whether they are co-resident, and any IPC donations made in the income year. If you are unsure of a figure, use zero — the tool will show you the gap.

Step 3 — Run the four scenarios

The tool generates four parallel scenarios automatically:

  • Current Plan — your tax position based on reliefs already entered

  • Max SRS — effect of topping up SRS to the S$15,300 cap before December 31

  • Max CPF Top-Up — effect of full S$8,000 personal top-up plus qualifying family top-ups

  • Full Forensic Max — all levers deployed simultaneously, including donation deduction at the amount you specify

Each scenario shows final chargeable income, final tax bill, delta against your current plan, and the saving expressed in plates of chicken rice at Ya Kun prices.

Step 4 — Export your results

Use the PDF export to save your scenario comparison for reference when filing at myTax Portal. The export includes your inputs and all four scenario outputs. It is not a tax return — it is a planning reference.

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