GST Challenges in E-commerce

GST Challenges in E-commerce

If you sell through Amazon, Flipkart, or any marketplace — or if you operate one — two GST provisions define your entire compliance architecture. Section 52 TCS requires every marketplace to deduct tax at source on net taxable supplies and file GSTR-8 by the 10th of each month. Section 9(5) shifts the entire GST liability for notified service categories from the supplier to the platform. Add multi-state warehouse registration obligations, ONDC's fragmented participant model, and a high-volume return cycle that routinely breaks naive credit-note workflows, and e-commerce GST in FY 2026-27 is a system that rewards process design and punishes improvisation.

Who Qualifies as an E-commerce Operator Under GST?

Section 2(45) of the CGST Act 2017 defines an e-commerce operator (ECO) as any person who owns, operates, or manages a digital or electronic facility or platform for electronic commerce. The definition is deliberately wide.

It covers:

• Horizontal marketplaces — Amazon, Flipkart, Meesho, Myntra
• Quick commerce platforms — Blinkit, Zepto, Swiggy Instamart
• Aggregators in notified service categories — Ola, Uber, Urban Company, Zomato for restaurant delivery
• ONDC network participants who collect payment and facilitate supplies between buyers and sellers

This classification triggers three specific obligations that do not apply to ordinary businesses: mandatory GST registration with no threshold exemption, monthly GSTR-8 filing, and potential Section 9(5) liability. A D2C brand selling only from its own website is not an ECO — it discharges its own output GST and manages state registrations based on warehouse footprint.

Section 52 TCS: The Mechanics Every Operator Must Master

The Rate and the Taxable Base

Under Section 52 of the CGST Act, every ECO must collect Tax Collected at Source (TCS) at 1% on the net taxable value of supplies made through its platform by registered sellers — split as 0.5% CGST and 0.5% SGST/UTGST for intra-state supplies, or 1% IGST for inter-state supplies. The base is net value: gross supplies for the month minus returns and cancellations processed in that same month.

TCS applies only to supplies by registered sellers. Supplies by unregistered sellers feed into a different compliance question addressed under Section 9(5) and the unregistered supplier rules.

GSTR-8: Filing Mechanics and Hard Deadlines

GSTR-8 is the ECO's monthly TCS return on the GST portal. It must be filed by the 10th of the following calendar month — no extensions are routinely granted. It reports:

• GSTIN-wise breakup of supplies made through the platform
• Gross value, return/cancellation value, and net taxable value per seller
• TCS collected and the corresponding payment into the government's electronic cash ledger

Late fee: Rs. 200 per day of delay (Rs. 100 CGST + Rs. 100 SGST), capped at Rs. 5,000 per return. In addition, interest at 18% per annum applies to any TCS collected but not remitted. A large marketplace operating across all 28 states and UTs that files GSTR-8 even 26 days late hits the Rs. 5,000 cap in each state — an exposure of Rs. 1,40,000 in late fees before interest is counted.

How Sellers Claim TCS Credit

TCS deducted by the ECO is populated in the seller's GSTR-2B (generated after the ECO files GSTR-8). The seller claims this credit in their electronic cash ledger when filing GSTR-3B — this is a critical distinction from ITC, which flows into the credit ledger. TCS credit reduces the cash tax payable, not the ITC balance.

Step-by-step for sellers:

1. Download GSTR-2B for the month from the GST portal after the 14th.
2. Cross-check TCS credit in Part C of GSTR-2B against the marketplace's monthly settlement statement.
3. If the ECO filed GSTR-8 late (after the GSTR-2B generation date), the credit will appear in the following month's GSTR-2B — it is not lost, only delayed.
4. Escalate any GSTIN mismatches to the marketplace's partner support team before filing GSTR-3B, as incorrect GSTIN reporting in GSTR-8 blocks the credit entirely.
5. Claim the verified TCS credit in the appropriate cash ledger row of GSTR-3B.

Section 9(5) Reverse Charge: When the Platform Pays the Tax

Section 9(5) of the CGST Act (mirrored in Section 5(5) of the IGST Act) notifies specific service categories where the ECO is deemed to be the supplier and must pay GST — the actual service provider pays nothing on those supplies.

Notified Categories for FY 2026-27

When a Swiggy partner restaurant operates under the Composition Scheme and supplies through Swiggy, Swiggy pays 5% GST on the food order value. The restaurant pays zero GST on that supply. Swiggy cannot show this GST as a separate line item on the customer's order receipt — it is absorbed into the platform's operating cost.

How to Report Section 9(5) Liability Correctly

The ECO reports Section 9(5) outward supplies in Table 3.1(a) of GSTR-3B as taxable outward supplies, not in Table 3.1(d) (the reverse-charge inward supply table). This is a frequently made filing error that generates automated scrutiny notices because the system cross-validates ECO-type GSTINs against Section 9(5) supply reporting.

The actual supplier (restaurant, driver) excludes these supplies from their own GSTR-1 and GSTR-3B.

Worked Example: TCS, Credit Delay, and a Return Cycle

Scenario: Apparel Seller on a National Marketplace, April 2026

Facts:

• Seller: Kiran Fashions Pvt Ltd — GSTIN: 27AACCK1234A1Z5 (Maharashtra)
• Marketplace: PrimeMart (ECO with GSTINs across all states)
• April 2026 gross supplies through PrimeMart: Rs. 20,00,000
• Returns processed in April (on March 2026 orders): Rs. 2,00,000
• Net taxable supplies for TCS: Rs. 18,00,000
• Applicable GST rate on apparel (above Rs. 1,000): 12%

TCS Calculation (inter-state, IGST basis):

• TCS @ 1% on Rs. 18,00,000 = Rs. 18,000

PrimeMart files GSTR-8 by 10 May 2026 reporting Kiran Fashions' net taxable value of Rs. 18,00,000 and TCS of Rs. 18,000.

Kiran Fashions' GSTR-3B for April 2026:

• Output GST liability (12% × Rs. 18,00,000) = Rs. 2,16,000
• ITC available (fabric, packaging, freight) = Rs. 1,98,000
• Net cash liability before TCS credit = Rs. 18,000
• TCS credit from GSTR-2B = Rs. 18,000
• Cash GST payable: Rs. 0

Now Add the Late GSTR-8 Scenario

PrimeMart delays and files GSTR-8 on 18 May 2026 — eight days late. GSTR-2B for April is auto-generated on 14 May, before PrimeMart's GSTR-8 is filed. Result: Kiran Fashions' April GSTR-2B shows zero TCS credit.

Kiran Fashions must pay the full Rs. 18,000 in cash when filing GSTR-3B by 20 May 2026. The Rs. 18,000 TCS will surface only in the May 2026 GSTR-2B — a one-month cash blockage driven entirely by the ECO's delayed filing.

PrimeMart's late fee: Rs. 200 × 8 days = Rs. 1,600 per state GSTIN. Across 28 GSTINs, that is Rs. 44,800 — recoverable from PrimeMart, not from the seller, but the seller bears the cash flow cost in the interim.

This single scenario explains why sellers on high-volume marketplaces should track GSTR-8 acknowledgement numbers each month, not just their own return calendar.

Multi-State Nexus and Registration Architecture

When You Need Multiple GSTINs

Under the CGST Act, the same legal entity operating in multiple states is treated as a distinct person in each state — each state GSTIN is a separate taxable person for GST purposes. If you store inventory in FBA or third-party fulfilment warehouses across states, you must register in every state where a warehouse exists, regardless of your company's incorporation state.

Practical triggers requiring multi-state registration:

• Enrolling in Amazon FBA and enabling warehouses in Delhi, Maharashtra, and Karnataka
• Consigning goods to a regional distributor's warehouse for marketplace fulfilment
• Operating your own dark stores or micro-warehouses for quick commerce

Inter-State Stock Transfers Are Taxable Supplies

Moving goods from your home-state GSTIN to your own GSTIN in another state is a deemed supply under Schedule I of the CGST Act — the distinct-person rule applies. You must:

1. Raise a tax invoice from the transferring GSTIN to the receiving GSTIN.
2. Charge IGST on the transfer value (typically cost price or arm's length value).
3. Claim ITC in the destination-state GSTIN against that IGST.

The most common mistake here: treating inter-state FBA stock transfers as non-events. The result is an ITC block at the destination state (no invoice, no credit), a potential tax demand on the un-invoiced stock movement, and a mismatch in e-way bill records that raises a red flag during scrutiny.

ONDC and the Decentralised Commerce Problem

The Open Network for Digital Commerce (ONDC) disaggregates the traditional marketplace into multiple roles: the Buyer App (BAP), the Seller App (BSP/SAP), and the Logistics Service Provider (LSP). Each may be a different legal entity. This creates genuine ambiguity about which participant is the ECO for Section 52 TCS and Section 9(5) purposes.

Determining the ECO on ONDC

The ECO classification follows the payment flow and contractual relationship, not the technical architecture. In the dominant ONDC model, the seller app collects payment from the buyer app (or directly from the buyer) and is in privity of contract with the seller. This makes the seller app the ECO for TCS and GSTR-8 purposes.

Where the buyer app collects payment and remits to the seller app (or seller directly), the buyer app may be the ECO. This must be resolved in the network participant agreement before the platform goes live.

Practical steps for ONDC participants:

1. Explicitly designate in your participant agreement which entity is responsible for TCS deduction and GSTR-8 filing for each supply type.
2. Ensure your order management system produces GSTIN-wise supply reports in the format required for GSTR-8.
3. For Section 9(5) categories (restaurant orders through ONDC), confirm whether the seller app or buyer app is treating itself as the deemed supplier.
4. Where your role remains genuinely ambiguous, obtain a documented professional opinion or apply for an Advance Ruling before scale — the cost of an incorrect position multiplied across millions of transactions is not recoverable.

Cross-Border D2C, OIDAR, and Export Documentation

Exports Under Letter of Undertaking

If you sell goods to overseas buyers — through your own website, Amazon Global, or Shopify — this is a zero-rated supply under Section 16 of the IGST Act. You have two options:

• Export under a Letter of Undertaking (LUT) without paying IGST and claim a refund of accumulated ITC on inputs, or
• Pay IGST on export and claim a cash refund.

The LUT for FY 2026-27 must be filed on the GST portal before the first export shipment of the financial year — i.e., before any export in April 2026. A lapsed LUT means IGST must be paid on each export until the LUT is reinstated, tying up working capital in refund claims.

Shipping bill reconciliation: Refund claims on exports require your GSTR-1 export invoice data to match the shipping bill data on ICEGATE. Invoice number, port code, GSTIN, and taxable value must align exactly. Any mismatch blocks the refund in the ICEGATE-GSTN integration — the most common delay in export refunds is a simple formatting mismatch in invoice numbers between the two systems.

OIDAR Services and Overseas Platforms

Overseas entities supplying Online Information and Database Access or Retrieval (OIDAR) services — streaming, SaaS tools, e-learning modules, digital downloads — to non-GST-registered Indian consumers must register under GST and pay 18% IGST irrespective of their physical location. The place of supply is India. For FY 2026-27, these entities must also comply with the requirement to appoint a person in India for GST compliance purposes if they lack a fixed establishment here.

Returns, Refunds, and Credit Note Mechanics

E-commerce sees return rates of 15–40% in categories like apparel, footwear, and consumer electronics. Each return triggers a mandatory workflow that, if designed incorrectly, creates a persistent GST reconciliation gap.

The Correct Step-by-Step Process

1. Buyer initiates return; seller confirms receipt of returned goods.
2. Seller issues a credit note under Section 34 of the CGST Act, linked to the original tax invoice by invoice number and date.
3. The credit note must be issued by the earlier of: 30 September 2027 (for FY 2026-27 supplies) or the date of filing the Annual Return (GSTR-9). Missing this window means the output tax reversal is time-barred.
4. The credit note is reported in GSTR-1 (amendment tables for the original invoice period, or in the current month's GSTR-1).
5. The GST output liability is correspondingly reduced in GSTR-3B of the month the credit note is issued.
6. For TCS: the ECO cannot retroactively recover TCS already remitted to the government. Instead, the return value reduces the net taxable base in the ECO's GSTR-8 for the month in which the return is processed. April 2026 returns reduce May 2026's net taxable value in PrimeMart's GSTR-8.

What goes wrong: Sellers who issue credit notes but do not report them in GSTR-1 — or who reduce GSTR-3B output liability without a corresponding GSTR-1 amendment — create a supply-tax mismatch that auto-generates a scrutiny notice under Section 61.

Common Mistakes and Pitfalls to Avoid

• Claiming TCS credit in the ITC (credit) ledger instead of the cash ledger. TCS flows into your electronic cash ledger. Misclassifying it in GSTR-3B creates a short-payment of cash tax and excess ITC credit simultaneously — both generate demand notices.

• Not tracking whether the ECO filed GSTR-8 before the GSTR-2B generation date. If you file GSTR-3B assuming TCS credit that is not yet in GSTR-2B, you have effectively claimed a credit not available in your account. Verify GSTR-8 filing status on the GST portal before finalising GSTR-3B.

• Treating FBA warehouse transfers as zero-GST internal movements. Schedule I is unambiguous — distinct-person stock transfers are taxable supplies. The fix requires issuing a tax invoice, paying IGST, and claiming ITC at the destination GSTIN — all retroactively painful if missed for multiple months.

• Reporting Section 9(5) supplies in GSTR-3B Table 3.1(d) (inward reverse-charge table) instead of Table 3.1(a) (outward taxable supplies). GSTR system validation cross-checks ECO-category GSTINs for this error and triggers automated notices.

• Failing to renew the LUT for FY 2026-27 before the first April export. An LUT lapse forces IGST payment on exports and months of blocked capital in pending refunds.

• Applying a single HSN rate across a mixed-rate product catalogue. A seller offering both unbranded (5%) and branded (12%) apparel under a single HSN code understates tax liability. During an audit, every under-rated invoice carries principal tax, 24% interest per annum under Section 50, and potential penalties up to 100% of the tax involved.

• Not validating seller GSTINs on an ongoing basis after onboarding. GSTINs can be cancelled for non-compliance. An ECO that collects TCS from a seller whose GSTIN has since been cancelled, and remits it against that GSTIN, creates a credit that the seller cannot claim — and potentially exposes the ECO to joint liability for tax on unregistered supplies.

Audit Triggers and Internal Controls

GST analytics cross-validates GSTR-1, GSTR-3B, GSTR-8, e-way bill data, and GSTR-9 at scale. E-commerce businesses are disproportionately visible because their transactional data is entirely digital and pre-reconciled by the marketplace's own systems.

High-risk audit triggers for e-commerce sellers:

• GSTR-1 reported supply value is lower than the ECO's GSTR-8 for the same GSTIN and period — the system identifies the gap automatically and issues a Section 61 scrutiny notice.
• ITC claimed in GSTR-3B exceeds GSTR-2B for three or more consecutive months.
• Export refund claims where shipping bill BRC (Bank Realisation Certificate) data does not match GSTR-1 values.
• Persistent use of HSN 9999 or similar catch-all codes indicating absence of proper classification.

Preventive controls — what to do:

• Run a formal half-yearly reconciliation: extract marketplace settlement reports → match to GSTR-1 invoice data → cross-verify TCS credits in GSTR-2B. Do this for April–September 2026 no later than October 2026, well before the GSTR-9 filing deadline.
• Reconcile ITC claimed in GSTR-3B against GSTR-2B every single month. Excess ITC claimed and subsequently reversed attracts interest at 24% per annum under Section 50(3).
• Maintain a digital evidence trail for inter-state stock transfer invoices, export shipping bills, Section 34 credit notes, and LUT filings — auditors request these within 15–30 days of a notice, and manual reconstruction under pressure is unreliable.

Key Takeaways

• Section 52 TCS at 1% (as currently notified) applies to net taxable supplies — gross minus returns — made through the ECO; the credit reaches the seller's cash ledger via GSTR-2B, not the ITC ledger, and reduces cash tax payable in GSTR-3B.
• GSTR-8 is due by the 10th of each following month; a late filing by the ECO blocks the seller's TCS credit for that period and shifts cash impact to the next month — sellers should track ECO GSTR-8 acknowledgements, not just their own return deadlines.
• Section 9(5) makes the ECO the deemed supplier and sole GST payer for restaurant services, passenger transport, housekeeping, and unregistered accommodation services — the platform absorbs this cost and cannot pass it as a separate tax line to the consumer.
• Multi-state FBA or dark-store warehouses trigger mandatory GST registration in each state, and inter-state stock movements between your own GSTINs are taxable Schedule I supplies that require tax invoices and IGST payment.
• ONDC compliance requires explicit contractual designation of the ECO role among BAP, BSP, and LSP — the technical architecture does not determine tax liability; the payment flow and contractual relationship do.
• Credit notes for e-commerce returns must be issued under Section 34 and reported in GSTR-1 to be valid; TCS already remitted is not directly recoverable but adjusts through reduced net taxable values in subsequent GSTR-8 filings.
• The greatest audit risk is a divergence between your GSTR-1 reported supply values and the ECO's GSTR-8 data for the same period — reconcile these every six months and correct via amendment returns before the GSTR-9 annual return filing deadline for FY 2026-27.