GST, TDS & TCS Compliance Mistakes FY 2026–27 Guide
Avoid Costly Notices: 15 GST, TDS & TCS Compliance Mistakes You Must Fix in FY 2026–27
Staying compliant in FY 2026–27 requires more than just timely filing. Most tax notices arise from small but repeated gaps in reconciliation and reporting. Here are the most common mistakes along with practical fixes.

GST Compliance Errors

1. GSTR-1 vs GSTR-3B Mismatch
Issue: Differences in outward supplies may trigger notices and interest.
Provision: Section 37 & 39
Fix: Reconcile returns with books monthly and correct through GSTR-1A.
2. Incorrect ITC Claim or Non-Reversal
Issue: Ineligible ITC or missed reversals lead to penalties.
Provision: Section 16, Rule 42/43, Rule 37
Fix: Match ITC with GSTR-2B and track vendor payments.
3. ITC Without GSTR-2B Matching
Issue: ITC claimed without vendor compliance.
Provision: Section 16(2)(aa)
Fix: Follow strict GSTR-2B reconciliation.
4. 180-Day Rule Non-Compliance
Issue: Non-payment to vendors leads to ITC reversal.
Provision: Rule 37
Fix: Track ageing and reverse ITC if required.
5. ITC on Blocked Credits
Issue: ITC claimed on restricted expenses.
Provision: Section 17(5)
Fix: Maintain blocked ITC list and review regularly.
6. Incorrect Tax Rate / HSN
Issue: Wrong classification leads to tax mismatch.
Provision: Section 37 & Rule 46
Fix: Standardize HSN codes and validate data.
7. Delay in Credit Notes
Issue: Late reporting affects turnover accuracy.
Provision: Section 34
Fix: Record in same month and reconcile.
8. Tax Liability Adjustment Errors
Issue: Incorrect set-off causes interest liability.
Provision: Section 39 & 50
Fix: Review electronic ledgers before filing.

TDS & TCS Compliance Errors

9. Deduction or Collection Errors
Issue: Wrong rate, delay, or missed deduction.
Provision: Section 194 series / 206C
Fix: Verify sections and deposit timely.
10. TDS Return Errors
Issue: PAN mismatch or wrong challan mapping.
Provision: Section 200(3), 234E
Fix: Validate PAN and reconcile with OLTAS.
11. Late TDS Filing
Issue: ₹200/day late fee.
Provision: Section 234E, 271H
Fix: Maintain strict compliance calendar.
12. TDS Certificate Not Issued
Issue: Penalty and client issues.
Provision: Section 272A(2)(g)
Fix: Issue Form 16/16A on time.
13. TCS Applicability Errors
Issue: Wrong threshold calculation.
Provision: Section 206C(1H)
Fix: Track turnover customer-wise.

Return & Year-End Errors

14. QRMP / Composition Errors
Issue: Incorrect scheme filing or missed adjustments.
Provision: Section 39, Rule 44
Fix: Conduct quarterly reviews and reconcile post-year.
15. Filing Without Final Review
Issue: Errors remain unnoticed and lead to notices.
Provision: Sections 16, 37, 39
Fix: Apply maker-checker system and final checklist.
Key Takeaway: Monthly reconciliation and a proper review system can significantly reduce compliance risks. Focus areas for FY 2026–27 include GSTR-2B-based ITC and the 180-day payment rule.