The September 2026 guide
The sixth edition, published on 1 September 2026, covers first-time ACAP participation, independent testing, awards and continuing obligations. Its five appendices address review methodology, ordinary and certified post-ACAP reviews, transfers and common risks. ACAP is a voluntary risk-based assessment of GST controls; a checklist score alone cannot establish that a control works.
Three layers of controls
Entity controls provide management oversight, responsibilities, systems, communication, change management and monitoring. Transaction controls ensure correct tax treatment and capture at sales and purchase source. Reporting controls ensure complete extraction, compilation and submission. Missing Trader Fraud exposure forms part of the framework. ACAP particularly suits complex organisations, high transaction volumes and reliance on system controls.
Eligibility
Every key control needs at least 60% of listed or equivalent features. Latest financial statements require an unqualified audit opinion, including an audit if none was previously required. The business must be financially active with an operating record and at least three years of GST registration; proposed members of a new GST group also need three years. No current IRAS GST audit, good GST/income/property/withholding tax and Customs compliance, no outstanding tax and a qualified reviewer are required. Instalment amounts and the next GIRO deduction are excluded from outstanding tax. Surveys and technical-ruling clarifications are not themselves GST audits.
Application and timing
Complete SRC and submit GST F 23 through FormSG with score summaries; groups and divisions supply individual and combined summaries. For applications requiring review, IRAS states it notifies status within one month. Begin after approval and submit the full package within 15 months. Use the latest 12 months of filed returns or the past financial year. Added controls need at least three months of operation, extending the period where appropriate. Request deadline extension at least one month before the due date.
External reviewer qualifications
A public accounting entity or tax affiliate uses an SCTP Accredited Tax Advisor (GST) team lead, reports to an audit/tax partner or tax director and applies recognised controls-testing methodology. First-time firms undergo IRAS screening of resources, audit experience, methodology, onboarding and GST proficiency. A consultancy without a qualifying accounting-entity connection cannot use this arrangement merely because it performs ASK or internal-audit work.
Internal audit and independence
An in-house internal-audit lead belongs to a professional accounting/auditing body, with an SCTP GST Practitioner or Advisor on the team. Report to an independent non-executive audit committee, directly or through an independently tasked committee; global teams need the corresponding overseas structure. Joint work follows lead-team eligibility. External firms that prepared/reviewed GST returns use a different period or an entirely separate team including the responsible partner/director. Process-design/documentation staff cannot review their own work.
Premium and Merit
First awards last five years for Premium and three for Merit. Premium normally requires at least 80% at entity, sales, purchase and reporting levels and overall; Merit requires 60% at each and overall. Premium reflects integrated effective controls and regular monitoring; Merit allows less integration and ad-hoc monitoring with improvement measures. IRAS considers errors, effects and remediation. It may permit additional verification after improved controls operate at least three months or longer as required.
Benefits and penalty relief
Benefits include fewer GST interventions, quicker refunds absent anomalies, faster rulings/issues and applicable MES/IGDS/ACMT scheme auto-renewal. Major anomalies or policy-related risks still permit intervention. First ACAP gives one-time relief for genuine non-wilful past errors voluntarily disclosed, if extra tax is settled and Premium/Merit attained. This extends the normal VDP one-year grace period, subject to IRAS review; otherwise ordinary VDP reduced penalties may apply.
Trend analysis
Compare the review year with the previous 12 months and its individual return periods. Reconcile supplies to revenue and non-revenue financial-statement/management-account items and all return figures to listings and adjustments. Explain fluctuations, turnover differences and purchase-to-supply ratios in Annex 2. Groups may analyse totals but must provide member/unit contributions for planning.
Single/divisional representative units
Selected units jointly cover at least 50% of total supplies and taxable purchases, include higher-risk units and comprise at least 50% of all business units. Supplies include standard-rated, zero-rated and exempt; purchases include standard-rated and zero-rated. Combining units as one requires common systems/controls, central GST decisions and no segmental-reporting requirement, while covering all major income streams. In the four-unit example A has 55% of supplies but 20% of purchases: A+C or A+D meets coverage; higher-risk D must be included where relevant.
GST group selection
Two-member groups select both unless a member is inactive or wholly intra-group. Larger groups include the representative, cover at least 50% of external supplies and taxable purchases and at least half the active/non-wholly-intra-group members, with riskier members included. In the five-member example A reaches 50% of both values but two others remain necessary for the count test. Risk indicators include outsourcing, new systems, related parties, partial exemption, CA/RC/OVR and staff turnover.
Records and test period
Provide SRC, trends, ownership/function charts, source-to-return processes, tax decision trees and requested information. Identify non-revenue GST items: gifts above S$200 where input tax was claimed, payroll recoveries, assets, benefits and marketplace/group/branch transactions. For each unit select six months within the 12-month period, not necessarily consecutive or the same across units. Significant categories outside these months require alternative checking or reselection.
Entity review in two stages
Interview personnel and inspect evidence across control environment, activities, systems, change management, communication and monitoring. Gaps may require extra transaction/reporting tests. Reassess after these tests: a written policy does not justify an effective rating where staff ignore changed models or repeat errors. Record gaps in the factual report and Annex 5.
Walk-through and controls testing
Trace major sales/purchases from initiation and classification to recording and listings. Demonstrate system tax logic and compare manual decisions with guidance. Test staff knowledge and preventive/detective controls under recognised audit methodology. Similar work reduces testing only if performed for the same period and aligned with GST objectives and relevant units; document reasons. Shared systems may consolidate walk-throughs without losing coverage.
Material transactions and sample expansion
Test exceptional-value, new-model, complex, related-party, netting, asset, lease, scheme, deemed-supply and CA/RC/OVR transactions in every applicable category. Check value, tax rate, timing, classification, legal conditions and documents. Increase samples if controls fail or material items exceed minimums. Include cash receipts, journals and manual billing outside normal invoice modules.
Initial supply sample numbers
Per unit normally use 10 standard-rated and 20 zero-rated samples. Non-regulation-34 businesses with over 90% standard-rated supplies use 20 and 10 respectively. Non-regulation-33 exempt supplies require five for ordinary mixed-exempt businesses, or 20 for regulation-34 businesses and residential developers; inapplicable where only regulation-33 exemptions exist. Out-of-scope needs five, schemes ten. Banks can combine zero/exempt/out-of-scope. CA made/received each needs 2–12 and RC 5–15; use higher minimum without other standard-rated supplies. OVR remote services and low-value goods each need five. Received CA/RC checks both input and output tax.
Initial purchase sample numbers
Per unit use 20 standard-rated, five zero-rated, ten suspended-tax imports, ten tax-paid imports and ten scheme purchases; CA needs two and RC five, checking input and output tax. Where full input recovery is unavailable, inspect the entire year for RC hidden in out-of-scope/non-taxable accounts, including foreign loans, inter-company charges and foreign creditors. Minimums assume effective controls and enough material-item coverage.
Documentary and cross-border tests
Check valid tax/CA/RC invoices, import permits, consignee, SGD amounts and periods. Inputs relate to business taxable activities; wrongly charged OVR GST is not claimable. Verify exports, third-country location, CA eligibility and schemes. Connected-person imported services use market value when consideration is lower; relevant overseas-group/branch allocations may exclude permitted salaries, wages, interest and proportionate mark-ups. OVR low-value supply includes transport/insurance; identify marketplace, redeliverer and own overseas-establishment transactions.
Testing GST reporting
Choose one return period within the test period and trace extraction to submission with preparer/approver. Decentralised arrangements test each selected unit and consolidation team. Reconcile every figure to listings and working schedules, including unselected units, and recompute where needed. Examine manual changes, residual input apportionment, deemed supplies, unpaid RC invoices and approval evidence.
Findings and technical clarification
Record gaps/errors with audit evidence and explain scope deviations. Seek technical concurrence preferably at least three months before deadline. September 2026 changes require a tabulated request summary in Annex 5 section 3 and detailed separate cover letter following IRAS guidance. Supporting documents need not accompany ACAP/renewal requests upfront but are retained on request. Quantify affected-year values or period values with extrapolation pending ruling. The responsible partner/director or authorised internal-audit head signs according to the lead arrangement.
Error quantification
Quantify errors across all 12 months and all units, including unselected ones, plus recurring prior-year errors. If difficult, examine at least three months and justify extrapolation without waiting for IRAS agreement. Proxies are not allowed for additional tax claims or over-accounted tax refunds. Tax-impact errors must be quantified unless ASK concession applies; incomplete disclosure may lead to rejection/protective assessments. Removed GST-group members still require past-five-year coverage as measured at the due date or submission, whichever earlier.
Remediation and the full report
Assess ripple effects, other mitigating controls and whether adjustments or major system changes are needed. Optional extended review tests improved controls operated at least three months and adds a factual-report addendum and Annex 5. Deliver the factual report, SRC, trends, charts, process documentation, gaps/errors follow-up, ACAP declaration and any available risk framework within the 15-month deadline.
Post-ACAP reviews and teams
First PAR uses latest 12 months filed at the end of status year one and finishes within 18 months of award. Final PAR, if not renewing, uses latest 12 months at Premium year four/Merit year two and is due six months before expiry. Select a higher-risk/value three months, check trends, recurrence, new processes and business changes, and report to board/audit committee. In-house leads need deep GST/process knowledge and preferably accreditation; external leads must be SCTP GST Advisor/Practitioner with comparable-business experience.
Ordinary PAR samples: single registrants
Standard-rated supplies/output tax:20–25; input claims:30–45. Substantially taxable businesses use zero-rated:30–45. Regulation-34 businesses/residential developers use zero-rated:20–30, exempt:30–45. Other businesses use one exempt sample if only regulation-33, otherwise five non-regulation-33 samples or ten when these reach 10% of total supplies. Out-of-scope:five; import schemes:20–30; other schemes:ten; CA made/received:two each; RC:five; OVR remote services/low-value goods:five each. Inputs include imports, bad debts and unpaid-purchase repayments.
Ordinary PAR samples: groups/divisions
Samples apply to the whole group/entity, not each member/division. Standard supplies/output:20–30; inputs:30–60. Substantially taxable businesses use zero-rated:30–60; regulation-34/residential developers use zero-rated:20–45 and exempt:30–60. Other-business exempt rules stay one or five-to-ten. Import schemes:20–45; out-of-scope, other schemes, CA, RC and OVR retain single-registrant minimums. This differs from initial ACAP sampling per representative unit.
PAR sample exceptions
If transactions are fewer than minimum, inspect all. Increase towards maximum if minimum covers below 30% of value, unless all transactions have second-level checks or ASK pre-filing checklist was used. Overseas-principal import agents use 30 samples(single) or 45(group/divisions) and reconcile ME permits unless already controlled. Full-input-recovery-ineligible RC businesses test five extra RC transactions even if already in standard samples; if all standard supplies are only RC, use 20 or all if fewer and no extra sample. CA/RC checks both input/output. IRAS may approve reduction for analytical tools case by case.
Apportionment and new-process checks
Above de-minimis exempt supplies, verify residual input identification/apportionment. Exclude received CA, imported RC services/low-value goods and OVR marketplace/redeliverer underlying-supplier supplies from both standard recovery-formula numerator and denominator. Check duplicated inputs, gifts, reimbursements/disbursements, missing sales, extraction and purchases unpaid 12 months after due date. New systems, outsourcing/contracts/models need updated source treatment and controls, not just samples.
Completion declarations from February 2026
From 1 February 2026 every PAR requires FormSG completion declaration by deadline. Keep F 28 and appendices even if not submitted. Submit reports when IRAS requires extra review, business/operating/financial processes changed, PAR supports scheme application, or final review replaces renewal. First three include applicable errors/quantification/concession declarations and trends; Final PAR adds supply/exempt/input/refund/own-and-principal import working papers. Correct through F 7, or next F 5 only if administrative concession applies.
Certified Final PAR for schemes
A scheme user not renewing ACAP uses ASK methodology/sample sizes, not ordinary reduced PAR. An accredited in-house/external GST Advisor/Practitioner performs it, or in-house staff obtain external accredited certification under ASK procedures. Check earlier gaps, IRAS risks, new activities and controls. Submit F 28A, trends, error/concession details and transaction/import papers with completion declaration six months before expiry; externally certified in-house work adds certification summary. IRAS-discovered extra errors outside reviewed samples do not qualify for VDP relief through that review.
Revocation and continued oversight
Notify IRAS of going-concern-qualified/adverse financial opinions, qualified internal-control assurance, receivership/liquidation/creditor arrangements, cessation/inactivity, unmet requirements, false or misleading information, or negligent/wilful incorrect returns. Status may be revoked; serious PAR system errors can impose extra retention conditions. Regular checks remain advisable since delayed disclosure beyond VDP one-year grace can attract penalties.
Restructuring limits
Joining a non-ACAP group revokes individual status; leaving an ACAP group does not create individual status. Acquisition of a separate entity does not extend status, nor does disappearing into a non-ACAP acquirer transfer it. Appendix 4 permits specific whole-business transfers, all-ACAP group formation, survival after business absorption and qualifying additions with evidence and extra testing. Contact IRAS with entity IDs, scenario, facts, confirmations, documents and responsible declarant.
Whole-business transfer
The transferee must be GST-registered with no existing operations or ACAP status. The entire going concern, not a part, transfers with unchanged activities/processes/controls, management commitment and all accounting/ACAP records. Obtain consent before transferor GST cancellation, confirm same controls, complete SRC, document additions and declarant sign-off. Submit at least one month before transfer.
New group of ACAP entities
All proposed members have individual ACAP, retain systems/GST staff, update intra-group coding and group-reporting controls, and commit extra review. Submit F 23, each SRC and review commitment one month before group registration. Test intra-group exclusion, reporting and new processes. Formation before PAR: report with PAR; after PAR but before renewal: report within six months of registration.
Absorption and ACAP-member addition
A surviving ACAP entity absorbing non-ACAP business identifies risks, adapts controls, trains staff and tests reporting/new processes. Adding an ACAP member keeps activities/controls, updates intra-group treatment, provides each member previous-12-month values and tests exclusions/reporting/changes. Both cases before PAR report with PAR; after PAR but before renewal are covered during renewal. A separate acquired entity remains outside status.
Adding non-ACAP members
Per inclusion, projected external supplies and taxable purchases each cannot exceed 10% of enlarged-group respective 12-month totals, excluding dealings with the group. Incoming members need all controls at 60%-feature standard, unqualified latest statements and ASK review of pre-entry returns with findings within six months of entry. Provide confirmations, prior-year member values, updated flows and tests. Before PAR report with PAR; after PAR but before renewal report within six months of inclusion. Otherwise seek prior approval with risk mitigation and proposed extra work.
Renewal and common risks
Renewal uses a 12-month review year, three-month testing, narrower tax-classification walk-throughs and lower samples; control tests focus on new/major changes since PAR. An independent reviewer submits within three months after original expiry. Renewed Premium lasts six years, Merit four from expiry. Appendix 5 illustrates weak escalation, outsourced oversight, knowledge/system gaps, omissions of receipts/assets/related supplies, timing/export support, duplicate/unsupported/disallowed inputs, Customs-scheme misuse, extraction/overwriting, apportionment/unpaid-purchase adjustments and unreviewed anomalies. It is not exhaustive.
Official source
This article independently explains the substantive contents of the official PDF, including the relevant conditions, procedures and annexes. The linked document remains the authoritative source for its original wording, and later changes should be checked separately.
Read the official PDF ↗