Distinguish zero-rated supplies from exempt supplies by recording the legal basis and transaction route, not just whether the customer pays GST. Section 16 of the IGST Act covers exports and qualifying supplies for authorised operations to SEZ units or developers. Exempt supply is a separate CGST Act concept. Their credit, document and reporting consequences can differ, so a single “zero GST” label is too vague for reliable books.
Identify what makes the supply zero-rated
For an export of goods, preserve the relevant movement outside India. For an export of services, review every statutory condition, including place of supply, permitted receipt and the establishment relationship. For an SEZ supply, establish the actual recipient and authorised-operations conditions.
Do not treat a domestic customer intending to export later as automatically making your sale an export. Deemed exports also have their own notified framework and should not be merged with zero-rated supplies merely because the terminology sounds similar. Record the actual provision that covers the seller's supply.
Identify the exemption separately
An exempt transaction can arise from a nil rate, a notified exemption or another component of the statutory definition. Read the applicable entry, description and conditions for the supply date. A customer category or industry label does not establish every exemption.
For example, a business selling several educational or healthcare-related products and services cannot assume that the whole catalogue is exempt. Keep item or contract-level evidence. Where a condition changes the outcome, make the needed evidence visible to billing staff rather than allowing the percentage field alone to stand for the decision.
Compare the practical records
| Question | Zero-rated supply | Exempt supply |
|---|---|---|
| Basis | Export or qualifying authorised-operations SEZ framework | Applicable exemption, nil-rate or other statutory basis |
| Output route | Without payment under eligible bond/LUT, or permitted payment route | No output tax under the applicable exemption treatment |
| Credit review | Section 16 framework, subject to conditions and blocked-credit rules | Attribution and restriction or reversal rules require review |
| Document | Relevant tax invoice particulars and route endorsement | Bill of supply where the applicable provisions require it |
| Key evidence | Export or SEZ qualification and route conditions | Exact entry, conditions and relevant product or service facts |
The table is a record guide, not a substitute for the actual statutory conditions in each column.
Understand why credit differs
Section 16(2) allows input tax credit for making zero-rated supplies subject to section 17(5)'s blocked-credit provisions and other applicable conditions. That is different from assuming that no output tax collection always blocks credit. A qualifying LUT exporter may have eligible input credit even though the output invoice does not collect IGST under that route.
Exempt supplies require review of credit attribution and reversal under the relevant provisions. Common inputs and services used for taxable, zero-rated and exempt activities need a supported calculation. Do not reverse credit for a qualifying export simply because its output tax amount is zero, or retain all credit for an exempt activity because the business is registered.
Illustrative direct-input comparison
Assume a business incurs ₹1,00,000 plus ₹18,000 GST on an input service used directly for a qualifying zero-rated activity. The ₹18,000 requires the usual eligibility and blocked-credit review; zero-rating can permit credit under the statutory framework. An eligible refund, however, still needs its own route, computation and conditions.
If an otherwise comparable input service is used directly for an exempt activity, its credit treatment must be reviewed under the exemption-related restrictions instead. The identical purchase tax does not imply identical entitlement. This illustration does not determine a particular expense's eligibility or promise that the full ₹18,000 is refundable.
Keep route and rate distinct in the item master
Use separate fields for classification, taxability basis, export or SEZ status, route and tax amount. A zero-rated supply made through an eligible IGST-payment route can show positive IGST. A qualifying without-payment export can retain a real commercial value despite no IGST collection under the route.
Do not set the commercial price to zero or mark every export item permanently exempt. The same goods sold domestically may have a different output treatment. Store the transaction-specific evidence and customer or destination facts needed to select the proper route at billing.
Reconcile reporting categories independently
Compare sales registers with the appropriate outward-supply and other relevant return categories. A correct grand total can still conceal a misclassification between exempt and zero-rated turnover. Keep export, SEZ, exempt and other categories supported by their own schedules.
For mixed activities, reconcile the turnover used in any common-credit working with the actual statutory definitions and adjustments. Do not use one broad zero-tax sales total for every denominator or exclusion. Preserve the working and period so another reviewer can reproduce it.
Review changes without rewriting history
An exemption or route condition can change, and an export may later face a receipt or qualification issue. Keep the original decision, relevant dates and later facts. Investigate the appropriate adjustment rather than silently changing all earlier invoices from zero-rated to exempt in the master.
The practical distinction is the legal basis and its consequences. When the business records why output tax is or is not collected, which credit rules apply and what evidence supports the supply, invoices and GST reconciliations remain understandable beyond a misleading zero-percentage field.