Common Taxation Mistakes in the RES Exam and How to Avoid Them

TL;DR: Candidates often fail the taxation section by applying the wrong tax rates to joint buyers or miscalculating the holding period for Seller’s Stamp Duty (SSD). Success requires mastering the 'highest applicable rate' rule for ABSD and distinguishing between the contract date and legal completion date for duty triggers.

One of the most common Taxation mistakes RES exam candidates make involves Additional Buyer’s Stamp Duty (ABSD) for joint purchasers. When two or more individuals with different profiles (e.g., a Singapore Citizen and a Foreigner) buy a property together, the law dictates that the highest applicable ABSD rate applies to the entire purchase price. Many students mistakenly try to pro-rate the tax based on share of ownership, which is a major distractor in Paper 2 MCQs. For example, if a Singapore Citizen (1st property) and a Foreigner buy a residential property together, the foreigner's rate (currently 60% as of recent cooling measures) applies to the full value, regardless of whether the foreigner owns 1% or 99%.

This confusion often arises because candidates assume tax is 'fair' and proportional. In the RES exam, examiners use scenarios where a couple with mixed residency statuses buys a home to see if you will fall for the pro-rated calculation trap. Remember, for the RES exam, which requires a 75% passing score (60 out of 80 marks), getting these high-weightage calculation questions right is critical. For RES exam candidates, this topic falls under Taxation in Paper 2. You can practice questions on this in the Prepare app.

In the Singapore RES exam, ABSD for joint purchasers is always calculated by identifying the buyer profile with the highest tax liability and applying that specific percentage to the total purchase price or market value, whichever is higher, without any pro-rating between the parties involved.

A frequent source of Taxation exam errors is the calculation of the holding period for Seller’s Stamp Duty (SSD). Candidates often incorrectly use the 'Legal Completion Date' (the day keys are handed over) instead of the 'Date of Contract' (the date the Option to Purchase was exercised) to determine if the three-year window has passed. Under the Stamp Duties Act, the holding period begins on the date of acquisition and ends on the date of disposal, both of which are defined by the contract date.

Tax Type	Trigger Point	Basis of Calculation
Buyer’s Stamp Duty (BSD)	Date of Acceptance/Exercise	Purchase Price or Market Value
Additional Buyer’s Stamp Duty (ABSD)	Date of Acceptance/Exercise	Profile-based (Citizenship/Count)
Seller’s Stamp Duty (SSD)	Date of Disposal/Sale	Selling Price or Market Value
Property Tax	Ownership (Annual)	Annual Value (AV)

Exam setters often create scenarios where a seller sells exactly three years and one day after the completion of their purchase, but only two years and eleven months after the exercise date. If you use the completion date, you’ll wrongly conclude no SSD is payable. To avoid Taxation mistakes, always look for the date the Option to Purchase (OTP) was exercised. As of 2026, with the registration fee for the RES exam at S$408.55, you cannot afford to lose marks on these timing nuances.

To correctly calculate Seller’s Stamp Duty (SSD) liability in the RES exam, you must measure the duration between the date the buyer exercised the Option to Purchase and the date the subsequent sale contract is signed, rather than using the physical move-in or legal completion dates.

Candidates frequently struggle to distinguish between Property Tax and Income Tax on rental income. To avoid Taxation mistakes, you must remember that Property Tax is a tax on property ownership and is calculated based on the Annual Value (AV) of the property, not the actual rent collected. Conversely, Income Tax is levied by IRAS on the actual net profit derived from renting out the property.

In Paper 2, a common distractor involves providing a scenario with both a high 'Annual Value' and a lower 'Actual Rent.' Candidates often mistakenly use the actual rent to calculate Property Tax. This error stems from real-world confusion where landlords focus on their cash flow. However, the IRAS guidelines are clear: Property Tax uses the AV (the estimated annual rent the property could fetch if it were rented out).

According to the CEA Annual Report, there are over 33,000 registered property agents in Singapore as of 2026, and all had to master this distinction. If a question asks for the 'tax payable on ownership,' look for the AV and the progressive tax rate table. If it asks for 'tax on rental income,' you are dealing with Income Tax. For more on this, check our Taxation topic overview.

Property Tax in Singapore is an asset tax determined by multiplying the property’s Annual Value by the prevailing tax rates, whereas Income Tax is a separate levy applied to the actual rental profit earned by the owner after deducting allowable expenses like maintenance and interest.

Goods and Services Tax (GST) is a major hurdle in the Taxation section. A common mistake is failing to identify when GST is applicable. In Singapore, GST is only charged on the sale and lease of non-residential (commercial and industrial) properties. Residential properties are exempt from GST. Candidates often miss marks by either applying GST to a residential condo sale or forgetting to add it to a warehouse or office transaction.

Exam-setters often use Taxation tricky questions where a GST-registered company sells a commercial unit to an individual. Candidates must know that if the seller is GST-registered, they must charge GST (currently 9% in 2026) on the purchase price. Another trap is the 'Option to Purchase' price—does it include or exclude GST? Unless stated otherwise, the price is usually exclusive of GST in exam scenarios.

Understanding GST is vital because it significantly impacts the buyer's cash outlay. For RES exam candidates, this topic falls under Taxation in Paper 2. You can practice questions on this in the Prepare app. Mastery of GST rules ensures you don't provide wrong financial advice in the simulation questions of the exam.

In the RES Examination, GST must only be factored into calculations for commercial or industrial property transactions involving GST-registered entities, as residential property sales and leases are legally exempt from GST under current Singapore tax regulations administered by the Inland Revenue Authority.

Q: Is ABSD calculated before or after BSD? A: They are independent. Both are calculated based on the higher of the Purchase Price or Market Value. You do not add BSD to the price before calculating ABSD. This is a common mathematical error in the exam.

Q: Does the SSD rate change based on the seller's citizenship? A: No. Unlike ABSD, Seller’s Stamp Duty (SSD) rates are the same for Singapore Citizens, PRs, and Foreigners. The only factor is the holding period. This is a classic distractor where the exam provides the seller's nationality to tempt you into choosing a different rate.

Q: How do I handle a mixed-use property (e.g., a shop-house) for GST? A: You must pro-rate. The residential portion is exempt, while the commercial portion is subject to GST. This requires careful reading of the floor area or value split provided in the question.

Preparing for these Taxation tricky questions requires consistent practice. The Prepare app offers over 2,000 practice questions, including 116 specifically on Taxation, to help you navigate these nuances. With a 75% passing threshold, every calculation counts.

Successful RES candidates avoid common taxation errors by treating Buyer’s Stamp Duty and Additional Buyer’s Stamp Duty as separate calculations based on the same valuation, while ensuring that Seller’s Stamp Duty remains focused solely on the holding duration regardless of the seller’s residency status.