Skip to main content

GSTR-1 JSON generator

The firm's own monthly outward-supply return, generated from CAPilot's invoice data, ready to upload at gst.gov.in.

GSTR-1 export

What's working​

  • One filing-period at a time — month picker defaults to last month (CA filing rhythm — GSTR-1 due 11th of next month).
  • Live preview — counts (B2B / B2CL / B2CS / distinct customers), totals (taxable / tax / total invoice value) before download.
  • JSON sections generated per GSTN spec:
    • b2b — invoices to registered customers (recipient has GSTIN), full invoice-level detail per recipient
    • b2cl — inter-state B2C, invoice value > ₹2,50,000, invoice-level detail per POS state
    • b2cs — other B2C aggregated by (POS state, rate)
    • hsn — HSN-wise summary across all sections, IGST vs CGST+SGST correctly split per-line by the invoice's intra/inter classification (mandatory since FY 2022-23)
    • doc_issue — range of invoice numbers issued in the period + cancelled count
  • GST math:
    • POS state = firm's GSTIN state → intra-state → CGST + SGST (each = rate / 2)
    • POS state ≠ firm's GSTIN state → inter-state → IGST (= rate)
  • Status filtering — only "live" invoices (Sent / PartiallyPaid / Paid / Overdue) appear in b2b/b2cl/b2cs sections. Cancelled invoices count only in doc_issue.cancel. Draft / WrittenOff / Rejected excluded entirely.
  • Firm-GSTIN-missing banner with a link to Firm Settings — won't try to generate a return without a valid firm GSTIN.
  • Empty-period state — "No live invoices in May 2026. GSTR-1 will be nil for this period." with Open Invoices link.

Verified math​

Synthetic test — 3 invoices for HSN 998212 (mixed intra-state Maharashtra + inter-state Karnataka):

InvoicePOSTaxableTax (18 %)Split
TUL/0001MH (intra)₹10,000₹1,800CGST ₹900 + SGST ₹900
TUL/0003KA (inter)₹2,50,000₹45,000IGST ₹45,000
TUL/0004MH (intra)₹5,000₹900CGST ₹450 + SGST ₹450
HSN row—₹2,65,000₹47,700IGST 45,000 + CGST 1,350 + SGST 1,350

The HSN row correctly splits IGST and CGST+SGST per the underlying line's intra/inter classification — same HSN sold to mixed POS aggregates into one row with the right component breakdown.

What's stub / pending​

  • CDNR / CDNUR (credit / debit notes — CreditNote table exists but not yet wired into the GSTR-1 generator)
  • EXP (export invoices — rarely used by small CA firms)
  • NIL (nil-rated / exempt — rare)
  • GSTR-3B — companion summary return. Natural next slice; same data pipeline.
  • GSTR-2B reconciliation — match firm purchases against 2B JSON downloaded from gst.gov.in, flag mismatches.

Upload path on the GST portal: Login → Returns → GSTR-1 → Prepare Offline → Upload.