Allowable business expenses under the Income Tax Act: Frequently asked questions

Raffles Corporate Services works with a panel of corporate and employment law firms; this article is general information, not legal advice. Allowable business expenses under the Income Tax Act are costs that a Singapore company can deduct against its taxable income because they were wholly and exclusively incurred in the production of income, as opposed to private, capital, or disallowed expenditure. Getting this classification right affects how much corporate tax a company pays and how clean its filing is when IRAS reviews the computation.

What counts as an allowable business expense under the Income Tax Act?

Section 14(1) of the Income Tax Act 1947 sets the general test: an expense is deductible if it is revenue in nature (not capital), and was wholly and exclusively incurred in the production of the company’s income during the basis period. Typical allowable items include staff salaries and CPF contributions, rental of business premises, utilities, professional fees for accounting or legal services connected to the trade, advertising and marketing costs, and general insurance premiums on business assets. Capital expenditure, such as the cost of acquiring machinery or renovating premises, is not immediately deductible under section 14 but may instead qualify for capital allowances or specific renovation and refurbishment relief under separate provisions.

Who needs to understand these rules?

Every Singapore-incorporated company preparing its annual tax computation needs a working grasp of allowable versus disallowable expenses, since the tax computation starts from the accounting profit and adjusts it for items the Income Tax Act treats differently from financial reporting standards. This matters most for SME finance staff and directors who review draft accounts before filing, bookkeepers and accountants preparing the tax schedule, and any business owner personally guaranteeing company debts who wants to understand why the accounting profit and the chargeable income are two different numbers on the same set of financial statements.

What are the specific rules and exclusions to check before claiming an expense?

Section 15 of the Income Tax Act 1947 lists specific disallowed expenses, including private or domestic expenses, capital withdrawn from the business, any sum not wholly and exclusively laid out for the trade, and certain specifically disallowed items such as fines and penalties, which remain non-deductible even where the fine arose from carrying on the business. Entertainment expenses are a frequent grey area: client entertainment connected to generating income is generally deductible, but expenses with a strong private or non-business character are not. Medical expenses for staff are deductible up to a cap, usually expressed as a percentage of total remuneration, unless the company has implemented a qualifying portable medical benefits scheme, in which case the cap can be higher. Motor vehicle expenses for S-plated private cars used by the business are generally disallowed under a longstanding restriction, while commercial vehicles and Q-plated or RU-plated vehicles used for business are treated differently.

What are the cost and timeline implications of getting expense classification wrong?

Misclassifying a capital item as a revenue expense, or claiming a specifically disallowed cost, understates chargeable income and can trigger an IRAS query or audit. Where IRAS raises an assessment after discovering an understatement, the company faces the additional tax payable plus a penalty that can run up to 400% of the tax undercharged in cases of wilful intent, though penalties for genuine errors are typically lower and may be reduced where the company voluntarily discloses the mistake before IRAS starts a review. A standard tax computation review by an accountant for an SME typically takes 1 to 2 weeks once full records are available, while an IRAS query response, if one is raised, is commonly expected within 14 to 30 days of the request letter. Keeping clean, contemporaneous documentation at the time an expense is incurred, rather than reconstructing the rationale a year later, is the single biggest factor in avoiding delay.

What is the step-by-step process for preparing the expense schedule in a tax computation?

First, start from the audited or management accounts profit and loss statement. Second, identify every expense line that may be capital in nature, specifically disallowed, or subject to a statutory cap, such as medical expenses or entertainment. Third, add back any disallowed or capital item to the accounting profit. Fourth, separately claim capital allowances on qualifying fixed assets under the relevant provisions, since these replace the accounting depreciation that was added back. Fifth, cross-check related-party transactions, directors’ remuneration, and any donations, since these have their own specific tax treatment distinct from ordinary trade expenses. Sixth, finalise the computation and retain supporting invoices, contracts, and board approvals for the statutory record-keeping period, generally five years, in case IRAS requests substantiation later.

What are the most common mistakes businesses make when claiming expenses?

The most common error is claiming private motor vehicle running costs for an S-plated car as a business deduction, which is specifically restricted. The second is deducting the full cost of office renovation or fit-out as a revenue expense in the year incurred, when much of it is capital and should instead be claimed under the renovation and refurbishment deduction scheme or as capital allowances where applicable. The third is failing to apportion expenses that have both a business and a private element, such as a home office or a mixed-use vehicle, resulting in an overstated claim. The fourth is omitting supporting documentation entirely and relying on a bank statement alone, which is generally insufficient on its own to substantiate the business purpose of an expense if IRAS asks for more detail.

How does expense classification interact with GST input tax claims?

A separate but related question SMEs often raise is whether an expense that is allowable for income tax purposes automatically allows the company to claim GST input tax on the same cost. The two regimes are independent: an expense can be income-tax deductible but have its input tax specifically disallowed under the GST (General) Regulations, the clearest example being costs relating to private motor cars, club subscriptions, and certain medical and insurance expenses for staff, which are blocked for GST input tax claims even where the underlying cost is deductible for income tax. Finance teams preparing both the GST return and the tax computation from the same set of accounts should check each expense against both rule sets separately rather than assuming one clears the other.

How should a company treat employee benefits-in-kind for tax deduction purposes?

Benefits provided to staff, such as subsidised meals, transport allowances, club memberships, and non-contractual bonuses, are generally deductible to the company as part of staff remuneration costs, provided they are incurred wholly and exclusively for the business and properly recorded as employment costs. The more complex question is usually on the employee’s side, since many of these benefits are separately assessable as taxable income to the employee under the Inland Revenue Authority of Singapore’s benefits-in-kind guidelines, even though the company itself can still claim the deduction. SMEs introducing a new flexible benefits scheme should check both sides of this equation: whether the cost is deductible to the company, which is usually straightforward, and whether it needs to be reported on the employee’s Form IR8A, which is a separate compliance obligation under the Income Tax Act 1947 that is easy to overlook when a benefit is informally introduced without payroll or HR sign-off.

Training costs sit in a similarly favourable position: expenditure on staff training that is relevant to the employee’s current role in the business is generally deductible as a revenue expense, and certain training costs may separately qualify for enhanced deductions under current incentive schemes such as the Enterprise Innovation Scheme, subject to its own qualifying conditions and caps. Training that equips an employee for a role unrelated to the current business, however, sits closer to a capital or private expense and is more likely to be challenged if claimed as a straightforward deduction.

What should a company do if IRAS queries a specific expense claim?

If IRAS issues a query letter asking for substantiation of a specific expense line, the company should first locate the original invoice, contract, or approval for that item, then prepare a short written explanation of the business purpose connecting the expense to the company’s income-producing activity. Where the expense genuinely falls into a grey area, such as entertainment with a partly social character, it is usually more efficient to voluntarily apportion the claim to the clearly business-related portion than to defend the full amount and risk a protracted dispute. Companies that respond promptly, typically within the 14 to 30 day window IRAS specifies in its letter, and that provide organised documentation on the first request, resolve the large majority of these queries without further correspondence or penalty.

FAQs

Are directors’ fees an allowable business expense?
Directors’ fees are generally deductible to the company provided they are approved in accordance with the company’s constitution and are not excessive relative to the services rendered, though they are taxed as income in the hands of the director.

Can start-up costs incurred before incorporation be claimed?
Certain pre-commencement revenue expenses incurred within one year before the first day of the accounting period in which the business earns its first dollar of income may be deductible as if incurred on that first day, subject to the usual wholly-and-exclusively test.

Is interest on a business loan deductible?
Interest expense is generally deductible where the borrowed funds are used to produce income, but interest relating to non-income-producing investments or private use is restricted.

Can a company deduct donations as a business expense?
Donations to approved Institutions of a Public Character typically qualify for a separate tax deduction at an enhanced multiple of the donation amount, rather than being treated as an ordinary section 14 trade expense.

What records should be kept to support an expense claim?
Original invoices, receipts, contracts, and, where relevant, board approval for significant expenditure, retained for at least five years as required under the Income Tax Act 1947.

Related guides

For the common mistakes and rejection reasons on this exact topic, see our companion article, Allowable Business Expenses Under the Income Tax Act: Common Mistakes and Rejection Reasons. For a related deduction that is frequently confused with ordinary business expenses, see Tax Treatment of Keyman Insurance Premiums in Singapore: The Five IRAS Conditions. Where a company with cross-border staff also needs to check pass conditions affecting payroll classification, see S Pass Job Scope Change: When MOM Requires a Fresh Application.

Authoritative references for this article include the Inland Revenue Authority of Singapore at iras.gov.sg for the e-Tax guides on deductible and disallowable expenses, the Accounting and Corporate Regulatory Authority at acra.gov.sg for financial reporting obligations that interact with the tax computation, and the Ministry of Finance at mof.gov.sg for the policy basis of Singapore’s corporate tax deduction framework.

Need help with this? Call, SMS or WhatsApp +65 8501 7133, or email [email protected]. Raffles Corporate Services works with a panel of corporate and employment law firms; this article is general information, not legal advice.