Prepare GSTR-3B from GSTR-1 + 2B

GSTR-3B is the monthly summary return. ThynkTax derives every cell automatically.

Sources

• Outward supplies (3.1) - from GSTR-1
• Inward RCM (3.1d) - from RCM self-invoices in the period
• ITC available (4A) - from IMS-accepted 2B + RCM credits
• ITC reversal (4B) - from Rule 37 (180-day unpaid), Rule 42/43 (proportional reversal for exempt supplies), 17(5) blocked
• Net ITC (4C) - auto-calculated
• Late fee + interest - calculated under Section 50 / Rule 88B

Validation

50+ checks run automatically - see the full validation list. Common ones:

• Output tax = sum of all 3.1 boxes
• ITC available ≤ 2B + provisional credit
• 43B(h) MSME deferred-payment warning if any vendor > 45 days
• RCM auto-reversal of self-deducted ITC

Filing

After validation:

1. Approve - Tier 2 agent gate (CA signs off)
2. File - Tier 3 gate. Even after CA approval, the actual portal submission requires a final tap.
3. Submit cash payment - the challan is generated and the cash ledger is debited.
4. ARN returned; return moves to FILED.