How long to keep business records in Singapore: IRAS rules

Singapore pairs the shortest headline retention period of the major five jurisdictions, five years, with some of the most explicitly digital-friendly rules: electronic records need no approval, and originals can go once a proper copy exists. The teeth are real, though: up to $5,000 in penalties and, more painfully, disallowed deductions and input tax claims for anything unsubstantiated. IRAS sources are in the Sources section.

Five years, anchored to the Year of Assessment

Companies and self-employed persons must keep proper records and accounts of business transactions for at least 5 years from the relevant Year of Assessment ^[1] . GST-registered businesses keep the records supporting each GST return for at least 5 years ^[2] .

The YA anchor adds a year of effective life compared with a document-date rule: a receipt from January 2025 belongs to YA 2026, so its 5 years run to the end of 2030, nearly six years after the spend.

What must be kept

IRAS’s record-keeping guides expect a complete substantiation chain ^{[1] [2]} :

• Source documents: receipts, invoices (including tax invoices for GST), vouchers, import and export permits.
• Accounting records and schedules: ledgers, the link from each return box to its source documents.
• Bank records for the business accounts.

For GST-registered businesses, the tax invoice rules are the strictest part: input tax claims need valid tax invoices, and a missing or defective invoice is a disallowed claim regardless of whether the spend was genuine.

The format rules: digital by default

Singapore’s position is unusually clean ^{[1] [2]} :

• Source documents can be kept in physical or electronic form.
• No approval is needed from the Comptroller to keep records electronically or in imaging systems, provided the requirements in IRAS’s record-keeping guides are met.
• Once a proper electronic copy exists, the paper original does not need to be retained.

This makes the compliant workflow and the convenient workflow the same workflow: image every document at arrival, store it against the transaction it supports, discard the paper. The InvoiceNow rollout reinforces the direction of travel, but note that transmitting invoice data to IRAS does not replace record-keeping; the underlying records must still be kept ^[3] .

Concessions for small businesses

IRAS publishes a Simplified Record Keeping regime for qualifying small businesses, set out in its e-Tax Guide on simplified record keeping requirements ^[1] . The simplification reduces the granularity of the accounting records a qualifying business must maintain; it does not shorten the 5-year period or remove the need to keep source documents for business expenses. Treat it as a reduction in bookkeeping formality, not in evidence. In the other direction, GST registration ratchets requirements up: once registered, the business inherits the full tax-invoice discipline of IRAS’s record keeping guide for GST-registered businesses, and the documentation standard is checked in practice every time a refund-position F5 return draws review.

The penalties

Failure to keep proper records carries penalties of up to $5,000, with imprisonment of up to 6 months in default of payment ^[1] . The quieter, larger cost: IRAS can disallow expense claims, capital allowances, and GST input tax claims that records cannot support ^[1] . For a GST-registered business, a year of unsupported input tax claims dwarfs the statutory penalty.

A retention policy that runs itself

Because IRAS accepts electronic records without ceremony, the entire obligation reduces to one habit: every receipt and supplier invoice gets imaged and attached to its ledger transaction on the day it arrives. That habit is what ExpenseFlow automates for Singapore businesses: documents are captured by photo, email, or drive pick-up, extracted and coded with the correct GST treatment (including blocked input tax categories under Regulations 26 and 27), and synced into Xero with the source document attached. When IRAS asks about a YA 2026 deduction in 2030, the evidence is two clicks from the ledger line, not somewhere in a five-year-old box. The filings and the records both live in the accounting platform; ExpenseFlow makes sure the records actually get there.