Construction business expenses in Singapore: GST on every project, blocked input tax, and capital allowances

Singapore keeps construction tax simple in structure but specific in the details that cost money: GST applies to every construction job, the input tax on motor cars is blocked, and plant goes through capital allowances rather than depreciation. There is no Construction Industry Scheme and no statutory mileage rate, so the work is in getting the GST treatment and the capital classification right. Every point below is sourced from IRAS guidance in the Sources section.

GST applies to all construction, residential included

A GST-registered company charges GST on all construction services, whether the property under construction is residential or non-residential ^[1] . This catches firms that assume residential work is exempt: the sale or lease of residential property is exempt, but the construction service is taxable.

Where the construction service relates directly to land or improvements situated outside Singapore, it can qualify as an international service and be zero-rated ^[1] . The Singapore GST guide covers the rate history and the standard-versus-zero-rated split in more depth.

Blocked input tax: the motor car rule

Singapore’s input tax rules deny credit on specific categories no matter how business-related they feel. Under Regulations 26 and 27, you cannot claim input tax on the purchase and running costs of motor cars, or on benefits provided to family members or relatives of staff ^[2] .

For a construction company this is a clean line: GST on a lorry, excavator, scaffolding, and materials is recoverable; GST on a company car is not. Coding purchases correctly at capture time keeps the GST return defensible.

Capital allowances on plant and machinery

Plant, machinery, and equipment are capital, so they are deducted through capital allowances, which IRAS grants in place of depreciation (accounting depreciation is not deductible) ^[3] . A company claims capital allowances when the expense is incurred, spread according to the asset and the basis chosen ^[3] . Pure consumables and small tools used up in the work are deductible as ordinary business expenses rather than capitalised.

Vehicles, tools, and protective gear

Singapore has no statutory per-kilometre rate, so vehicle costs are claimed on actual business records, and for motor cars the GST is blocked regardless. A company-rate mileage log is the usual way to evidence business use for income tax. Tools, protective equipment, and safety gear required for the work are deductible; ordinary clothing is not.

Progress claims and timing

Construction contracts in Singapore typically run on progress claims, and GST timing follows the normal time-of-supply rules: the earlier of when payment is received or a tax invoice is issued. For a contractor billing in stages across a long project, that means each progress claim is its own GST event, and the input tax on the materials and subcontractor work behind it is claimed in the period the supplier’s tax invoice falls. Keeping the supplier invoices matched to each stage is what makes the GST F5 reconcile cleanly. A retention sum held back by the customer is still part of the contract value, so it should not be lost from the records even though the cash arrives late. Getting the classification (standard-rated, zero-rated, or blocked) fixed at the point each document arrives keeps both the income tax computation and the GST return defensible at year end.

Where ExpenseFlow fits

The Singapore construction load is classification: every purchase needs the right GST treatment (claimable, blocked, or zero-rated) and the right capital-versus-expense call, and both decisions are easiest at the moment the document arrives. ExpenseFlow captures each receipt and supplier invoice, extracts the GST and line detail, and syncs the transaction into Xero or QuickBooks Online with the image attached, building the five-year record archive IRAS expects. Its compliance checks flag input tax that Regulations 26 and 27 block, such as GST on a private motor car or a benefit for a relative of staff, so a disallowed credit is caught before it reaches the GST F5 rather than in an IRAS query. It surfaces the data your accountant needs to file the F5 and the corporate return, with the statutory exceptions left for human confirmation; it does not file the returns for you.

Common mistakes

• Treating residential construction as GST-exempt because residential property sales are exempt ^[1] .
• Claiming input tax on a company car, which Regulation 27 blocks ^[2] .
• Capitalising consumables, or expensing plant that should run through capital allowances ^[3] .
• Assuming a per-kilometre mileage rate exists and claiming on that basis.