GST Audit & Due Diligence (Pre-Acquisition & Vendor)

GST due diligence is a review of a counterparty's GST compliance position, commissioned by the party on the other side of a transaction — an acquirer reviewing a target, an investor reviewing an investee, or a buyer reviewing a prospective vendor. A GST Audit & Health Check, by contrast, is a business reviewing its own compliance for its own risk management. The methodology overlaps significantly — both check registration status, return-filing history, ITC eligibility, and RCM compliance — but GST due diligence is specifically time-boxed to a transaction decision and its findings are designed to feed into deal terms or an onboarding decision, not just an internal remediation plan.

Not necessarily. Under Section 85 of the CGST Act, where a taxable person transfers their business (in whole or as a going concern) to another person, the transferor and the transferee are jointly and severally liable to pay tax, interest, or penalty due up to the time of transfer, unless the outstanding tax dues have been discharged by the transferor at the time of transfer. In practical terms, this means an acquirer of a business — through a share purchase or a business transfer — can be pursued by the department for GST liabilities relating to a period before the acquirer ever controlled the business, if those liabilities were not settled or specifically ring-fenced at the time of transfer.

Under Rule 36(4) read with Section 16(2)(aa) of the CGST Act, your entitlement to claim Input Tax Credit on a purchase is conditional on that credit actually appearing in your GSTR-2B — which in turn depends on your vendor having correctly and timely filed their own GSTR-1. If a vendor delays filing, files incorrectly, or has their registration cancelled, the ITC you claimed based on their invoice can effectively be denied or must be reversed, even though you paid the GST-inclusive invoice value in good faith. You then bear the reversal along with interest under Section 50, while your recovery route against the vendor is a commercial/contractual claim, not an automatic GST-law remedy.

Registration status and history across every GSTIN (active, suspended, or previously cancelled); the return-filing history for GSTR-1, GSTR-3B, and GSTR-9/9C, including on-time filing discipline; Input Tax Credit eligibility — matched against GSTR-2B, screened for Section 17(5) blocked-credit categories, and checked for the Section 16(4) time-bar; reverse charge mechanism compliance on notified categories; any pending scrutiny notices, audit intimations, show-cause notices, or litigation; the electronic cash and credit ledger position; and any pending refund claims. The specific depth and emphasis is scoped to the transaction — an acquisition of a manufacturing business with import/export activity is scoped differently from onboarding a services vendor.

Section 36 of the CGST Act requires records to be retained for a minimum of 72 months (6 years) from the due date of filing the annual return for the relevant year, and this practically sets the outer boundary of what is available for review. In most acquisition due diligence engagements, we focus the detailed transaction-level review on the most recent 2–3 financial years, while still checking the litigation and notice history over the full retention period, since an old but still-pending dispute can be just as relevant to successor liability as a recent one.

Not usually. A finding during due diligence is information that informs how the deal is structured, not automatically a deal-breaker. Common resolutions include a purchase price adjustment reflecting the quantified exposure, an escrow or holdback arrangement releasing funds only after a specified period or after the department confirms no further liability, a specific indemnity clause in the Share Purchase Agreement covering the identified exposure with an appropriate survival period, or a condition precedent requiring the seller to regularise the position (including possible voluntary DRC-03 payment) before completion. The right mechanism depends on the size of the exposure relative to deal value and how quantifiable versus contingent it is.

It is relevant for both, though the underlying legal exposure differs. In a share purchase, the target company itself does not change — its GSTIN, its historical liabilities, and its compliance history remain exactly as they were, simply under new ownership. There is no need to invoke Section 85 successor liability because the same legal person continues; however, every historical GST liability of the company is now effectively the buyer's problem through their ownership of the company. In a business transfer or slump sale, Section 85 joint-and-several liability specifically applies between transferor and transferee for the period up to transfer. Either way, independent GST due diligence is warranted — the legal mechanism of exposure differs, but the practical need to know what you are inheriting does not.

The transfer of a business as a going concern, where all assets and liabilities are transferred together and the transferee continues the same business, is treated as a supply of services but is specifically exempted from GST under Notification No. 12/2017-Central Tax (Rate), subject to the transfer genuinely qualifying as a going-concern transfer under the conditions the notification and subsequent clarifications set out. If the transaction is instead structured as an itemised sale of specific assets without transferring the business as a functioning whole, GST typically applies to each asset at its applicable rate. Getting this classification right at the structuring stage has a direct GST cost consequence, and we review the proposed transaction structure specifically for this before completion, not after.

We work through each category of finding — under-paid RCM, ineligible ITC claimed, time-barred ITC not reversed, GSTR-1/3B/books mismatches, pending notices with an estimated exposure range — and separately quantify the tax amount, the applicable interest under Section 50 (18% per annum generally, 24% per annum specifically on wrongly-utilised ITC) as of the anticipated completion date, and, where a demand has already crystallised, any penalty already assessed or reasonably likely under Section 73 or Section 74 depending on whether fraud or suppression is alleged. This gives the acquirer a rupee-value range to negotiate against, rather than a qualitative 'there may be some risk' statement.

In rough order of concern: any history of registration cancellation (even if since revoked/reinstated), since it often signals an underlying compliance or solvency issue; a pattern of consistently late GSTR-3B filing, which both signals weak internal controls and, for a vendor, directly threatens the buyer's own ITC timing; unresolved or unexplained mismatches between GSTR-1, GSTR-3B, and the books of account; any pending Section 74 (fraud/wilful misstatement) proceedings, which carry materially higher penalty exposure and reputational risk than a Section 73 matter; and unusually large or growing ITC claims relative to turnover without a clear underlying business explanation.

Yes, and this is a useful secondary output, particularly relevant for valuation purposes in an acquisition. We routinely identify unclaimed inverted duty structure refunds, excess electronic cash ledger balances sitting unclaimed, and unutilised ITC on zero-rated exports under LUT that was never claimed as a refund. These represent a real, quantifiable asset value that should factor into the valuation or purchase price discussion, alongside the liability-side findings that typically dominate a due diligence conversation.

Yes, where relevant to the target's or vendor's profile. Section 51 TDS under GST applies to specified categories of deductors (government departments, local authorities, and certain notified persons), and Section 52 TCS applies to e-commerce operators. Where the target operates in either capacity, or is a supplier subject to TCS deduction by an e-commerce platform, we verify correct deduction/collection, timely deposit, and correct filing of GSTR-7 or GSTR-8 as part of the broader review, since non-compliance here carries its own penalty exposure that would transfer with the business in an acquisition.

The underlying checks — registration validity, filing history, RCM discipline — overlap substantially, but the objective and depth differ. Acquisition due diligence needs to quantify successor liability exposure across the target's full historical compliance position, including litigation and cash-ledger review, because the acquirer inherits the business as a whole. Vendor due diligence is narrower and more forward-looking: its primary purpose is to assess whether this vendor's filing behaviour is reliable enough that your own ITC on future invoices from them is not at risk — it is less about historical successor liability and more about ongoing counterparty risk.

PNPC quotes a fixed, agreed fee based on the number of GSTINs and periods under review, the transaction type (acquisition versus vendor onboarding), the sector and transaction complexity (imports, exports, real estate, works contracts generally require deeper review), and the timeline required. The fee is confirmed in writing before work begins. Vendor onboarding due diligence for a single vendor is typically priced well below a full acquisition due diligence engagement, reflecting its narrower scope.

A single-GSTIN acquisition target with reasonably organised records can typically be reviewed in 3–4 weeks from receipt of complete data to a final report; a single vendor onboarding check can typically be completed in 1–2 weeks. Where the deal timeline is tighter than this, we prioritise the highest-risk categories first — registration status, litigation history, and any obvious red flags — and deliver an initial risk flag ahead of the fuller report, so the deal team has actionable information even before the complete review concludes.

The electronic cash ledger reflects GST paid in cash (via challan) by the taxpayer, and the electronic credit ledger reflects Input Tax Credit available for utilisation, both maintained on the GST portal for every GSTIN. We check both as of the review date for two reasons: an unusually large, unexplained cash or credit ledger balance can represent unclaimed refund entitlement or an accounting discrepancy worth investigating, and a near-zero or negative-trending credit ledger balance can signal a business that has been aggressively utilising credit close to the margin, which is relevant to assessing ongoing GST payment capacity and working capital position.

Yes, meaningfully. Real estate and works contract businesses carry distinctive GST complexity: the valuation of construction services (including the land-value deduction mechanism), the applicability and rate structure for ongoing versus new projects, ITC restrictions specific to construction of immovable property under Section 17(5)(c)/(d), and RERA-linked timing of GST liability on advances received. These are areas where errors are both common and individually high-value, and our due diligence for a real estate target specifically scopes for them rather than applying a generic trading-business checklist.

Section 73 covers tax short-paid, unpaid, or ITC wrongly availed/utilised where fraud, wilful misstatement, or suppression of facts is not alleged — the penalty exposure is comparatively modest, particularly where paid voluntarily. Section 74 covers the same categories where fraud or wilful misstatement is alleged, and carries materially higher penalty exposure, up to 100% of the tax amount in the most severe cases, along with reputational and potential prosecution risk. When we identify a pending matter during due diligence, we specifically note which provision it falls under (or whether it has been reframed from one to the other during proceedings), because this materially changes both the quantified exposure and the urgency of addressing it before completion.

PNPC reviews and advises on the GST-specific representations, warranties, and indemnity provisions in the draft transaction documents to confirm they accurately reflect our due diligence findings and provide commercially reasonable protection — for example, ensuring the indemnity survival period is long enough to cover the department's own assessment and audit timelines, and that the representations specifically address the categories of exposure we identified rather than relying on generic tax boilerplate. We work alongside your transaction counsel on this — drafting the full legal agreement is counsel's role, but ensuring the GST content within it is technically accurate and complete is where we add the most value.

Yes, and it carries its own specific risk profile. SEZ units and exporters under LUT typically have limited or no output tax liability on their zero-rated supplies but often carry significant accumulated ITC and refund claims. Our due diligence for such a target verifies LUT validity and renewal history, checks that refund claims filed are properly documented (matching shipping bills, FIRC/BRC, and export invoices), and confirms there is no pending refund rejection or recovery proceeding that would represent a liability rather than the asset the accumulated credit position might otherwise suggest.

Typically, yes. Most engagements extend through deal-document review (representations, warranties, indemnity language) and, where the parties agree a historical shortfall should be regularised, into post-completion support for voluntary DRC-03 filing or department correspondence. For vendor onboarding, PNPC's involvement typically concludes with the risk score and onboarding recommendation, though we recommend building periodic re-verification into the ongoing vendor relationship rather than treating the initial due diligence as a one-time, permanent clearance.

GST due diligence is typically run as a coordinated but distinct workstream alongside income-tax due diligence and general financial due diligence, since each covers a different legal and risk domain even though they draw on overlapping underlying data (books of account, financial statements, trial balances). PNPC frequently runs GST and income-tax due diligence together for the same target, sharing the underlying financial data request and cross-referencing findings — for example, a GST turnover mismatch and an income-tax revenue recognition question often point to the same underlying transaction issue and are best resolved with visibility into both workstreams simultaneously.

Yes. Every GST due diligence engagement concludes with a structured written report: an executive summary of overall GST risk, a detailed findings section rated by materiality and likelihood, the specific legal basis for each finding, a quantified exposure range where the finding can be quantified, and — for acquisitions specifically — a recommended risk-allocation mechanism (price adjustment, escrow, indemnity, or condition precedent) for the transaction team and legal counsel to act on. For vendor onboarding, the report includes a clear risk rating and onboarding recommendation.

PNPC's GST due diligence specifically covers the Indian GST position under the CGST/SGST/IGST framework. For the UAE side of the transaction, our Dubai office separately reviews UAE VAT compliance under the framework administered by the Federal Tax Authority — a distinct tax system with its own rules and filing cycles. Where the transaction involves cross-border elements — for example, an Indian subsidiary of a UAE holding structure, or intercompany service arrangements between the two entities — we coordinate the India and UAE reviews as a single engagement narrative so the findings from both jurisdictions are presented together to the deal team.

A self-declaration or compliance certificate from the target or vendor is, by definition, not independently verified — it reflects what the counterparty says about its own compliance, which is precisely the information asymmetry due diligence exists to test. PNPC independently pulls and verifies data directly from the GST portal and the underlying books, rather than relying on a representation. We are also positioned to support you through deal-document drafting and, if needed, post-completion regularisation or department correspondence — a self-declaration alone offers no such continuity if an issue later surfaces.

Yes. PNPC scopes engagements proportionately to transaction size and risk — a modest-value vendor onboarding or a small asset acquisition does not warrant the same depth of review as a large business acquisition with multi-state operations and litigation history. For smaller engagements, we typically focus on registration validity, recent filing consistency, and any obvious red flags, rather than the full multi-week methodology described for larger acquisitions, while still flagging if the initial scan surfaces something that genuinely warrants deeper review.

Across both acquisition targets and onboarding vendors, under-paid or mistimed reverse charge mechanism liability — particularly on GTA freight and legal/professional fees — and ITC claimed on categories blocked under Section 17(5) are consistently the two most frequent findings. Both categories tend to be recurring, systemic errors rather than one-off mistakes, meaning the exposure compounds across every return period they went unaddressed, which is exactly why they surface as material findings once a due diligence review looks at the full period in scope rather than a single return.

A limited preliminary scan is possible using public GST portal data — checking a GSTIN's active/cancelled status and, in some cases, filing frequency indicators visible on the public search. This can be useful at the earliest, pre-LOI stage to form an initial view. However, a full due diligence review — testing ITC eligibility, RCM compliance, litigation history, and ledger balances — requires the target's or vendor's cooperation in sharing return copies, books of account, and departmental correspondence, since none of that transaction-level detail is publicly available. Most acquisition processes formalise this cooperation through the due diligence request list issued once exclusivity or a term sheet is in place.

Yes. GST rates in India were rationalised with effect from September 2025 into a simplified structure, and we specifically verify that the target or vendor has correctly transitioned its HSN/SAC-linked rate classification to the current structure for the period under review, rather than continuing to apply pre-rationalisation rates by oversight. A business that has not correctly updated its billing and return-filing systems following a rate change can carry either an under-collection liability (if it undercharged customers) or an over-collection/refund complication (if it overcharged), both of which are relevant to the buyer's or acquirer's risk assessment.

We maintain a structured core questionnaire and document request list covering registration, filings, ITC, RCM, litigation, and ledger position, which forms the baseline for every engagement. This baseline is then adapted to the specific transaction — additional sector-specific questions for real estate, exports, or e-commerce businesses, additional successor-liability-specific questions for an acquisition, or a narrower, faster-turnaround version for a routine vendor onboarding check. Starting from a proven baseline while tailoring the depth to the actual transaction keeps the process efficient without sacrificing coverage of the areas that matter most for that specific deal.

If you are the seller in an acquisition or the vendor being reviewed by a prospective large customer, it is worth commissioning your own independent GST health check in advance of the buyer's due diligence request, rather than responding reactively to their findings. Identifying and, where appropriate, voluntarily regularising any genuine gap before the buyer's diligence team finds it independently gives you control over the narrative and the remediation timeline, and generally results in a stronger negotiating position than having the same issue surface as an unexpected finding in the buyer's report.