Multi-GSTIN APIs for Manufacturing — Inter-Plant Stock Transfers, Branch-Wise Reconciliation, Single OAuth
One OAuth token, 100+ GSTINs. Branch-wise GSTR-2B reconciliation across the whole group in a single call.
Connect your SAP S/4HANA with our SAP connector — all 14 GSTINs in one dashboard
The problem
For Group Finance Controller at a multi-plant manufacturer (auto, FMCG, capital goods). You have 14 GSTINs across plants. Inter-state stock transfers need IRN plus EWB on the same shipment. Branch-wise GSTR-2B reconciliation against the purchase register is a month-end nightmare — and one mismatch in one branch blocks the group GSTR-9.
How WhiteBooks solves it
- Multi-GSTIN OAuth scopes: one parent client_credentials token can act on behalf of all 100+ GSTINs in the group without separate logins.
- Stock-transfer pair endpoint: einvoice.generate_irn + eway.generate as a single idempotent call.
- Branch-wise GSTR-2B fetch parallelisable across all GSTINs; results normalised into one reconciliation report.
- Per-GSTIN GSTR-1 and 3B filing from the same authenticated session — no per-plant credentials.
Key APIs
| Tool / Endpoint | What it does | Path |
|---|---|---|
gst.fetch_gstr2b | Per-GSTIN, parallelisable | /api/v1/gstr2b/fetch |
gst.verify_gstin_bulk | Vendor master clean-up (100/call) | /api/v1/gstin/bulk-verify |
einvoice.generate_irn | Stock transfer IRN | /api/v1/generate-irn |
eway.generate | Stock transfer EWB | /api/v1/generate |
gst.file_gstr1 | Per-GSTIN monthly filing | /api/v1/gstr1/file |
Compliance angle
Multi-GSTIN consolidation, stock-transfer documentation (deemed supply), ITC restrictions on inter-state transfers, plant-wise GSTR-9 annual return, ISD (Input Service Distributor) credit allocation.
Live numbers
- Throughput: 1,000 invoices / EWBs per single API call (bulk mode).
- Latency: p50 87 ms IRN, p95 312 ms — live at whitebooks.in/status.
- Uptime: 99.994% rolling 30-day; 99.99% SLA with credits on Enterprise.
- Region: Mumbai + Hyderabad active-active; KSA in
me-south-1.
Sample architecture
Sample customer pattern
A capital-goods manufacturer with 14 GSTINs uses WhiteBooks as a single API surface across all plants. SAP S/4HANA pushes invoices via the WhiteBooks SAP connector; e-Invoice + e-Way Bill are paired on a single call for stock transfers; GSTR-2B reconciliation runs nightly across all plants and surfaces mismatches before month-end close.
Frequently asked questions
Can one OAuth token act on behalf of all our 14 GSTINs?
Yes. Register your parent organisation once; we provision a single client_credentials token with multi-GSTIN scope. Every API call carries the acting GSTIN in the path or body, and our gateway validates it against your scope without re-authentication.
How does branch-wise GSTR-2B reconciliation work at scale?
gst.fetch_gstr2b is parallelisable — we run all 14 GSTINs concurrently and normalise the JSON into a single reconciliation feed (matched / unmatched / partial-match). Our SAP, Oracle, and Dynamics connectors plug this feed directly into the purchase ledger.
What about stock transfers between plants?
Stock transfers are a deemed supply under GST so they need both IRN and EWB. Call einvoice.generate_irn + eway.generate with the same line items and we ensure document linkage so your group GSTR-9 reconciles cleanly at year-end.
Do you support SAP / Oracle / Dynamics / Tally?
First-party connectors for SAP ECC 6.0+, S/4HANA, Oracle EBS / Fusion, Microsoft Dynamics 365, and Tally Prime / ERP 9. Each connector handles the multi-GSTIN routing, IDOC translation, and audit log retention automatically.
How do we file the group GSTR-9 with 14 GSTINs?
GSTR-9 is per-GSTIN, not group-level. We file 14 separate GSTR-9s but pre-reconcile across all GSTINs first so inter-plant entries net out before filing. The annual reconciliation report is a single export.
Get started
Related use cases: Logistics · Retail · Manufacturing · Fintech · Pharma · E-Commerce · SaaS · CA Firms · ERP Providers
Reference: All APIs hub · /docs/gst · /docs/einvoice · /docs/eway · Pricing · Architecture · Status · Changelog