Top 5 GST Compliance Mistakes SMBs Make in 2026

GST looks simple until the portal rejects your GSTR-1 at 11:47 PM on the due date. Here are the five mistakes we see most — and how Bill-o-Bill prevents each one.

1. HSN/SAC mismatches

Wrong HSN means your GSTR-1 upload fails. Bill-o-Bill validates HSN against the master before export.

2. ITC claimed without 2A/2B match

We auto-reconcile purchase invoices against GSTR-2B and flag only eligible ITC.

3. Late fee miscalculation

Our calendar tracks due dates per state and turnover, so you never miss a deadline.

4. Exporting from Tally via CSV

Use the 2-way connector — no CSV, no re-keying.

5. Ignoring e-invoice IRN status

Every invoice is checked for IRN validity before filing.