Abhishek Mishra
CTO, Sort String Solutions
GST e-invoicing in India has steadily expanded since 2020. The turnover threshold for mandatory e-invoicing has dropped from ₹500 Crore in 2020 to ₹5 Crore today. Most mid-market distribution companies are now in scope, and the compliance team's biggest source of GST notice exposure is no longer late returns — it is unmatched e-invoices and missing IRNs.
If you run distribution operations, this 14-point checklist will help you assess where you stand. We built it from the lessons of 45 SalesPort deployments where compliance has been a primary use case. Most companies discover they pass 10 of the 14 points but fail on 4 — and those 4 are where GST notices originate.
Quick refresher: what GST e-invoicing actually is
GST e-invoicing is not a separate invoicing system. It is a verification layer on top of your existing invoicing. Every B2B invoice you raise must be sent in real time (or near-real time) to the Invoice Registration Portal (IRP). The IRP assigns an Invoice Reference Number (IRN) and a QR code, which must be printed on the invoice. Without a valid IRN, the buyer cannot claim Input Tax Credit (ITC) on your invoice, and the invoice is technically non-compliant.
If you are running distribution at scale — hundreds of invoices a day — manual e-invoicing is unsustainable. Your DMS / ERP must integrate directly with the IRP.
The 14-point readiness checklist
1. Turnover threshold check
Confirm your group turnover for the most recent financial year. If it exceeds ₹5 Crore (current threshold as of 2026), e-invoicing is mandatory. If you are close to the threshold, treat it as if you are over — the threshold has only ever moved in one direction historically, and getting compliant proactively avoids a scramble at the next deadline.
2. Master data hygiene
Every B2B invoice references three master data sets: your GSTIN, the buyer's GSTIN, and the item HSN/SAC code. All three must be active, valid, and current on the day of invoice. We have seen distributors fail e-invoice generation because the buyer's GSTIN had been suspended without notification. Set up a monthly GSTIN validation routine for your top 200 buyers.
3. GSTIN validation at invoice creation
Your DMS should validate the buyer's GSTIN against the GST portal in real time when an invoice is being created. If the GSTIN is invalid, suspended, or unregistered, the system should block the invoice rather than letting it proceed to e-invoicing where it will be rejected anyway.
4. HSN code accuracy at the item level
Every line item on every invoice must carry the correct HSN/SAC code. For mixed-category distributors (FMCG + dairy + ancillary), HSN coverage gaps are common. Audit your product master to confirm every SKU has a valid 6-digit HSN code (8-digit if your turnover is over ₹5 Crore).
5. Item-level GST rate mapping
Each SKU should have its correct GST rate mapped — 0%, 5%, 12%, 18%, or 28% — in the product master. Bulk-edit imports often introduce rate errors. A wrong rate on a high-volume SKU surfaces in months of mismatched ITC claims and eventual GST notices.
6. Reverse charge mechanism (RCM) scenarios
If you procure from unregistered suppliers (small farmers, small vendors), or specific notified categories, you may need to raise self-invoices under RCM. Your DMS should support RCM invoicing as a distinct invoice type with the correct e-invoicing flow.
7. IRP API access and credentials
Confirm you have working IRP API access credentials (or a GSP relationship — a GST Suvidha Provider that wraps the IRP for you). Test the API in a sandbox before relying on it in production. Token expiry, rate limits, and authentication errors are the most common reasons e-invoices fail in production.
8. QR code on every B2B invoice
The QR code generated by the IRP must be printed on the physical or PDF invoice that goes to the buyer. Many ERPs generate the QR code but fail to render it on the standard invoice template. Audit your invoice templates — both PDF and printed — to confirm QR is visible and scannable.
9. E-way bill integration
If your invoice value exceeds ₹50,000 and goods are being transported, you also need a valid e-way bill. The e-way bill and the e-invoice are separate compliance objects but share the same data. Modern DMS platforms generate both from a single invoice submission. If you are managing them separately, you are doing 2x the data entry.
10. Tally / SAP / accounting sync
Whatever your accounting system (Tally, SAP B1, SAP HANA, others), it must consume the IRN and QR data alongside the invoice. If your sales team raises an e-invoice but your accounting system has no record of it, your books will diverge from your GST filings. SalesPort's Tally integration handles this two-way sync automatically — every IRN, every QR, every invoice flowing through to accounting with zero double entry.
11. Cancellation and amendment rules
E-invoices can be cancelled within 24 hours of generation. After that, you must raise a credit note. Your DMS should enforce this 24-hour rule — many compliance failures come from sales teams trying to "fix" an invoice 3 days later by editing it in the ERP rather than raising a credit note.
12. Credit note and debit note handling
Credit notes for sales returns and discount adjustments are themselves e-invoiced transactions. Many distributors successfully e-invoice their original invoices but skip e-invoicing credit notes — that gap creates ITC mismatches for the buyer and notices for both parties.
13. Bulk upload capacity for catch-up scenarios
If e-invoicing fails for 4 hours (IRP downtime, network issues), you may end up with 500 unsent invoices to catch up on. Your DMS must support bulk upload to the IRP without manual one-by-one re-entry. The IRP itself supports bulk JSON uploads — your software should expose that to the user.
14. Audit trail and retention
Every e-invoice request, response, IRN, and cancellation must be logged with timestamps for a minimum of 6 years (current Indian GST audit trail requirement). Plain log files are not enough — the audit trail should be queryable, exportable, and tied to the original invoice record.
Common failure modes we see
Across 45 deployments and dozens of compliance audits, four failure modes recur:
- The 2 AM rush: companies that batch all the day's invoices for end-of-day e-invoicing have a 2–4 hour window where things can fail and the team is asleep. Real-time e-invoicing on invoice generation fixes this.
- The "we'll fix it Monday" gap: e-invoicing fails on Friday evening for 50 invoices; the team waits till Monday; by then those buyers have raised disputes about missing IRNs and the team spends a week on cleanup.
- The buyer-side ITC mismatch: your e-invoice goes through but the buyer reports ITC mismatches anyway. Almost always: the buyer's GSTIN data on your master is stale, or your HSN/rate is wrong.
- The credit-note blind spot: original invoices e-invoiced flawlessly; sales returns (credit notes) never e-invoiced. ITC claims for the buyer break.
How a DMS helps
The honest answer: e-invoicing is fundamentally a compliance pipe. You can build it in-house, buy it as a standalone GSP service, or get it as part of your DMS / ERP. The third option is the cleanest because the same system that raises the invoice can submit it to the IRP, capture the IRN, render the QR code, sync to accounting, and log the audit trail — without three different vendors and four data hand-offs.
SalesPort handles all 14 points natively. We process 4.78 Lakh+ invoices annually for our 45 client companies with full IRN coverage, e-way bill integration, Tally/SAP sync, and 6-year audit trail retention. That is not us pitching — it is us pointing out that the 14-point checklist is a solved problem if you put it on the right platform.
The next deadline
The GST council reviews thresholds periodically. The trajectory has been clear — from ₹500 Cr to ₹5 Cr in five years. Anyone running B2B distribution above ₹2 Cr turnover should assume e-invoicing will apply to them within 12–18 months and start preparing now. Getting compliant proactively, with a checklist like this, is significantly cheaper than scrambling at deadline.
If you would like to see how SalesPort handles e-invoicing end-to-end for a distribution company, schedule a walkthrough and we will run through the 14 points live against a real client deployment.
Compliance is not glamorous, but it is the rare line item where being early is essentially free and being late is expensive. Run through the 14 points this quarter. The ones you fail are the ones to fix before the next GST cycle ends.