E-Invoicing Under GST: Applicability, Limits & Rules

If your business crossed ₹5 crore in annual aggregate turnover in any year from 2017-18 onwards, every B2B and export invoice you raise has to be reported to a government portal before it counts as a tax invoice. Miss that step and the document you sent your buyer isn't legally an invoice at all.

That's the part most finance teams underestimate. Your own accounting software still creates the invoice, the government just authenticates it and hands back an Invoice Reference Number (IRN) and a signed QR code. There's no government-generated PDF waiting for you to download.

For services exporters the questions get sharper. Does a zero-rated export invoice need an IRN? What goes in the shipping bill field when you've never shipped anything? This guide covers e-invoicing under GST as it stands in 2026: the rules, the mechanics, and the verification routes almost nobody explains properly.

• Who it applies to. Registered persons with annual aggregate turnover (AATO) above ₹5 crore in any financial year since 2017-18, for B2B supplies, exports, supplies to Special Economic Zones (SEZ), deemed exports and business-to-government sales.
• What it is. Reporting invoice particulars in JSON to an Invoice Registration Portal (IRP) under Rule 48(4) of the CGST Rules, and receiving back an IRN plus a signed QR code.
• The hard deadline. Taxpayers at AATO of ₹10 crore and above can't report an invoice more than 30 days after its document date, from 1 April 2025.
• The consequence. Under Rule 48(5), an invoice issued outside the prescribed manner "shall not be treated as an invoice".
• Cancellation. 24 hours on the IRP. After that, corrections run through GSTR-1 on the GST portal.
• Exports. Exports with and without payment of tax are both explicitly in scope, so a zero-rated services export invoice does need an IRN.

The obligations behind e-invoicing under GST sit in a handful of rules, and they're worth reading as a checklist rather than as background.

The legal basis, and why the IRN matters so much

Rule 48(4) of the CGST Rules requires notified persons to upload the particulars of an invoice in FORM GST INV-01 to the IRP and obtain an IRN. Rule 48(5) then says any invoice issued in a manner other than that prescribed one "shall not be treated as an invoice" (GSTN e-invoice/IRN System FAQ v1.3, Q1, Q2 and Q7).

The IRN is what turns your document into a tax invoice. Without it, a notified supplier has issued a piece of paper with no legal standing under GST.

The 30-day reporting rule

If your AATO is ₹10 crore or above, you can't report an invoice or a credit or debit note to any IRP more than 30 days after the document date. This took effect on 1 April 2025, under a GSTN advisory dated 5 November 2024 that lowered the trigger from ₹100 crore to ₹10 crore.

GSTN's own example: an invoice dated 1 April 2025 can't be reported after 30 April 2025. The portal's validation blocks it, so the document can't obtain an IRN through that route at all.

The document types and supply types in scope

Three document types are presently covered: the tax invoice, the credit note and the debit note (GSTN FAQ v1.3, Q8). Four supply types are covered: B2B, SEZ supplies with or without payment, exports with or without payment, and deemed exports (Q9).

• Exports are explicit - the FAQ lists "Exports (with/without payment)" as one covered category. So whether you export under a Letter of Undertaking (LUT) or with payment of IGST, e-invoicing under GST applies the same way. The with-or-without distinction is a transaction-type field in the schema rather than an applicability test.
• High-sea sales and bonded warehouse sales are out - these aren't a supply under Schedule III of the CGST Act (Q15).
• Imports are out - a Bill of Entry isn't an e-invoice document (Q16).

For the wider treatment of zero-rating, refunds and LUT mechanics, our guide to export of services under GST goes deeper than this page will.

HSN reporting

The AI Overview for this query names a 6-digit HSN code reporting requirement for taxpayers above ₹5 crore turnover. Our research confirmed HSN at item level as part of the schema and the QR code payload (GSTN FAQ v1.3, Q70(g)).

It did not locate the specific 6-digit mandate in a primary CBIC or GSTN e-invoice document. Confirm against the CBIC notification before publishing it as a stated rule.

Penalties

Section 122 of the CGST Act is the legal basis for penalties on e-invoicing failures (GSTN FAQ v1.3, Q68). The commonly cited figures are ₹10,000 per invoice or 100% of the tax due, whichever is higher, for non-issuance, and up to ₹25,000 for an incorrect invoice.

Those rupee amounts derive from the Section 122(1) penalty structure and are repeated across current tax commentary. They aren't spelled out verbatim in the GSTN FAQ itself.

Nothing in e-invoicing under GST changes how you raise an invoice. It changes what has to happen between raising it and sending it.

The end-to-end flow

• You create the invoice in your own ERP, accounting or billing system (GSTN FAQ v1.3, Q2, Q6).
• The details are reported to an IRP in JSON, following the notified FORM GST INV-01 schema (Q39, Q43).
• The IRP validates the data, including a duplicate check on the combination of supplier GSTIN, invoice number, document type and financial year, and can reject with error codes (Q56).
• On success the IRP returns signed JSON, never a PDF, carrying the 64-character IRN and the signed QR code (Q54 to Q58, Q61). IRN generation runs in under 200 milliseconds (Q35).
• The data auto-populates into GSTR-1 for you and GSTR-2A for your buyer, tagged with the IRN and IRN date (Q83).
• If both Part-A and Part-B e-way bill data were supplied at reporting time, the e-way bill is auto-generated. Missing Part-B has to be added later (Q84).
• Your ERP converts the signed JSON into the PDF you actually send, with the QR code printed on it (Q57, Q59, Q73, Q74).

Printing the QR code is mandatory under Rule 46. Printing the full 64-character IRN in text is optional, since it's already inside the QR code (Q60, Q62).

The schema, and how mandatory fields actually work

FORM GST INV-01 is the single national schema, notified in its current form by Notification 60/2020-Central Tax dated 30 July 2020. It's based on PEPPOL and Universal Business Language, customised for India (GSTN FAQ v1.3, Q39, Q41, Q42).

A few mechanics that trip people up:

• Cardinality notation - 1..1 and 1..n mean mandatory, 0..1 and 0..n mean optional. Ending in n means the field repeats (Q45).
• NIL, not blank - a mandatory field with no applicable value is reported as NIL (Q44).
• Conditional sections - an optional section such as e-way bill details contains fields that become mandatory the moment you invoke it (Q44(d)).
• Line-item ceiling - 1,000 line items per invoice (Q47).

E-invoice field groups at a glance

Mandatory: document details (number, date, type) · transaction type (B2B / SEZ with or without payment / export with or without payment / deemed export) · supplier details including GSTIN · recipient details, with recipient GSTIN conditional on applicability · line-item details including HSN, taxable value and tax · invoice totals.

Optional: export details (shipping bill number and date, port code) · payment details · reference details such as a PO number.

System-generated, not your input: the 64-character IRN and the signed QR code.

Sources: GSTN FAQ v1.3 Q8, Q9, Q47, Q54 to Q55, Q70. Field-level naming for the supplier, recipient, payment and reference groups is secondary-sourced; confirm against the notified INV-01 schema PDF. Published mandatory-field counts conflict across sources, so no count is stated here.

Exports with no shipping bill

This is the question every services exporter asks and almost no guide answers. The schema treats export details as one of the optional sections that exist "to cater to specific scenarios" (GSTN FAQ v1.3, Q44(c)). A pure services exporter has no shipping bill number and no port code to report.

The specific field-level optionality of shipping bill number, shipping bill date and port code is sourced only from secondary commentary in our research pass. Confirm against the notified schema PDF or a CBIC circular before relying on it operationally.

On the money side, your IRN evidences a GST-compliant export supply while your Foreign Inward Remittance Advice (FIRA) or electronic Bank Realisation Certificate (eBRC) evidences that the proceeds actually landed.

No government e-invoice document found in our research states a formal document-matching requirement between the two. Treat them as separate evidence tracks that a refund claim draws on together, and see our guide on FIRC for GST refund for the realisation side.

Cancellation and amendment

You get 24 hours from the time of reporting to cancel an e-invoice, via the Cancel API (GSTN FAQ v1.3, Q79). Three constraints sit on that window:

• No partial cancellation - it's in toto or not at all (Q81).
• No number reuse - a cancelled invoice number can't be used again, even inside the 24 hours (Q80).
• E-way bill block - cancellation isn't permitted if the linked e-way bill is active or has been verified by an officer in transit (Q79).

After the window closes, the IRP won't help you. Corrections go through the GST portal at GSTR-1 filing, or via the standard amendment mechanism if GSTR-1 is already filed, and the change is flagged to the proper officer (Q78).

If you're the recipient, verification is your job, not your supplier's. Three genuinely different questions hide inside "is this invoice valid", and e-invoicing under GST gives you a different tool for each.

The three verification jobs

Each row below answers a different question, so pick the tool by what you're actually trying to establish.

Search IRN returns the IRN, its status, the acknowledgement number and date, the signed QR code and the signed invoice. Verify Signed Invoice takes an upload of the signed JSON file (it must carry a .JSON extension) and checks the digital signature against the content (GSTN FAQ v1.3, Q69).

The Verify QR Code mobile app is the offline route, downloadable from the e-invoice portal under Help, Tools, and published as the GSTN e-Invoice QR Code Verifier (Q69).

What the signed QR code contains

The signed QR code carries a fixed set of parameters, so you can read a lot without going near a portal (GSTN FAQ v1.3, Section G, Q70, and the GSTN FAQs on Signed QR Code):

• Supplier GSTIN
• Recipient GSTIN, if applicable
• Invoice number as given by the supplier
• Date of generation of the invoice
• Invoice value (taxable value and gross tax)
• Number of line items
• HSN code of the main item, being the line item with the highest taxable value
• The IRN itself
• IRN generation date

If content has been altered after signing, signature verification fails and the e-invoice is invalid. The QR code prints at roughly 2 by 2 inches and has to stay scannable.

The enablement check has a caveat worth knowing

The enablement status page is built from GSTR-3B turnover data. The government page states plainly that the list may contain exempt entities, or entities for whom e-invoicing isn't applicable for some other reason (GSTN FAQ v1.3, Q25).

So enablement doesn't establish obligation. If you need certainty about a counterparty's turnover slab, Search Taxpayer and Know Your Supplier on the GST portal are the better route (Q25).

When verification fails

An invoice from an obligated supplier that carries no valid IRN or QR code isn't a valid tax invoice under Rule 48(5) (GSTN FAQ v1.3, Q7). That's the official position, and it's solid.

The knock-on for input tax credit is an inference from that invalidity, since ITC is generally conditioned on holding a valid tax invoice under Section 16 of the CGST Act. Our research didn't find a government e-invoice document stating an e-invoice-specific ITC-denial clause. Have a tax reviewer confirm before treating it as a hard causal rule.

Practically, ask the supplier to correct and re-report inside any applicable window, including the 30-day limit if their AATO is ₹10 crore or above. Until a valid IRN exists, treat the document as non-compliant for claim ITC in GST purposes.

The current generation threshold is ₹5 crore AATO, effective since August 2023. For the phase-by-phase history and the finer threshold questions, our dedicated page on the e invoice limit is the better read. What follows are the applicability rules that sit alongside that number.

• AATO is computed PAN-India. Add the turnover of every GSTIN registered under the same PAN, for any financial year from 2017-18 onwards.
• Once in, always in. Crossing the threshold in any qualifying year brings you into the mandate. A later drop in turnover doesn't take you back out.
• The covered supply set. B2B, business-to-government, exports with and without payment of tax, SEZ supplies, deemed exports, and credit and debit notes against any of those.
• Supplies to an SEZ are covered. The SEZ exemption applies to SEZ units as suppliers, not as recipients, so your supply into an SEZ still needs an IRN (GSTN FAQ v1.3, Q21).
• Government departments depend on registration. The mandate applies to supplies made to a registered person. If the department holds a GSTIN, name it as recipient and proceed normally. If it holds none, the obligation doesn't arise for that supply (Q13).

On B2C: as of August 2026, B2C invoices sit outside the mandatory regime and notified persons can't report them (GSTN FAQ v1.3, Q10). A voluntary pilot recommended by the GST Council on 9 September 2024 has been running since. Industry trackers describe a mandatory rollout targeted for 2026-27, but no CBIC or GST Council notification confirms that date.

Two different things get called "exempt" in this area, and confusing them causes real filing errors.

Exempt entities are notified classes of registered person who don't have to generate e-invoices regardless of turnover. Exempt supplies are goods or services that attract nil or no GST, which is a question about tax liability.

A fully taxable supplier can't skip an IRN because one line is an exempt supply. An exempt entity doesn't start e-invoicing because its supplies happen to be taxable.

Here are the notified exempt entities (GSTN FAQ v1.3, Q17).

Two additions that most published lists of e-invoicing under GST exemptions leave out:

• SEZ developers are not exempt. Only SEZ units are, per Notification 61/2020-Central Tax dated 30 July 2020. A developer meeting the turnover and other conditions must issue e-invoices (GSTN FAQ v1.3, Q19). Free Trade and Warehousing Zones are treated as a special category of SEZ and are exempt (Q20).
• Government departments and local authorities. The exemption is not blanket. The obligation follows registration status, as set out in the applicability rules above (Q13).

GSTN's own stated benefits are the ones worth repeating, because they're what the system was designed to deliver (GSTN FAQ v1.3, Q5).

• One-time reporting. Invoice data reported once flows into GSTR-1 automatically, tagged as e-invoice sourced.
• Automatic e-way bills. Part-A populates from the same reporting event when the data is supplied.
• Fewer reconciliation disputes. A single national schema means your buyer's system reads your invoice the way you wrote it.
• Faster credit visibility for buyers. Data lands in GSTR-2A without the buyer chasing you for a copy.
• Lower processing cost. Less manual re-keying, and fewer rejections traced back to typing errors.

For an exporter, the underrated benefit of e-invoicing under GST is audit readiness. Standardised, timestamped, signed invoice data is a much easier thing to hand a tax officer than a folder of PDFs.

The system is strict by design, and the failure modes are worth knowing before you meet them.

The 30-day window is a hard stop rather than a late fee

For AATO of ₹10 crore and above, an invoice not reported within 30 days can't be reported at all through that route. The IRP's validation refuses it. That's structurally different from filing late, because there's no penalty you can pay to get the IRN afterwards.

The 24-hour cancellation window is short

Price revisions and order cancellations discovered on day two can't be fixed by cancelling. You issue a credit note, amend GSTR-1, and raise a fresh invoice under a new number. Discrepancies between GSTR-1 and IRP data can trigger scrutiny under Section 61 or Section 73 of the CGST Act.

Rejections cluster around a few fields

The IRP rejects on duplicate invoice numbers, wrong recipient GSTIN, place-of-supply errors and HSN mismatches. Each rejection is a document you then have to re-report inside whatever window applies to you.

The penalty exposure

Non-issuance attracts ₹10,000 per invoice or 100% of the tax due, whichever is higher. An incorrect e-invoice attracts up to ₹25,000, under Section 122 of the CGST Act (GSTN FAQ v1.3, Q68; see the note on the rupee figures in the rules section above). Goods moving without a valid e-invoice or e-way bill can also be detained under Section 129.

ERP readiness

Smaller exporters carry the integration cost of e-invoicing under GST themselves. If your billing system can't emit the INV-01 JSON, you're either buying a connector, working through a GST Suvidha Provider, or keying invoices into the free offline Bulk Generation Tool the IRP publishes.

You have three sanctioned ways to get invoices onto an IRP (GSTN FAQ v1.3, Q32, Q33):

• Direct API integration from your own system, with specifications published at the NIC sandbox, einv-apisandbox.nic.in (Q85).
• API via a GSP or ASP. Application Service Providers route client data to the GST System through GST Suvidha Providers. There's no formal ASP empanelment, and no separate GSP category specific to IRP access (Q87).
• The free offline Bulk Generation Tool, downloadable from the IRP, for businesses without their own ERP.

Multiple IRPs are notified beyond the original NIC portal, with current secondary listings naming six live portals including NIC1, NIC2, Cygnet, Clear, EY and IRIS. Our research pass couldn't confirm the live count or the exact naming against the government's own IRP list, so treat the number as unverified.

On the payments side, an integration earns its place only if it removes a reconciliation step. Xflow's Zoho Books integration is live, syncing Zoho Books invoices with Xflow so export receipts match against the right invoice without manual tagging. Tally Prime is on Xflow's published plan for future integration, and isn't available today.

E-invoicing under GST handles the tax side of an export invoice. It does nothing about getting the money in, and that's where most services exporters lose time.

Xflow is built for Indian exporters receiving payments from overseas clients. It holds final Payment Aggregator - Cross Border (PA-CB) authorisation from the Reserve Bank of India for both exports and imports, as of February 2026, and is ISO 27001 and SOC 2 certified.

What that means operationally for an ITES exporter:

• Collections from 140+ countries in 25+ currencies, with over 20,000 businesses on the platform.
• Next business day settlement into your Indian account, priced against the live mid-market rate rather than a marked-up internal rate.
• eFIRA issued automatically for each settlement, so the realisation evidence your GST refund and EDPMS workflow need arrives without a bank request.
• Zoho Books sync, so the invoice you reported to the IRP and the payment you received line up in one place.

Nothing downstream in your compliance stack has to change. Your IRN process stays exactly as it is, and your FIRA trail keeps arriving.