Before 31 March: reconcile your input tax credit with GSTR-2B, pay any reverse charge and issue self-invoices, decide on QRMP for April to June (window closes 30 April), file a fresh LUT for 2027-28 if you export or supply to SEZs, set up a new invoice series for 1 April and check whether your turnover has crossed the ₹5 crore e-invoice threshold. Credit notes and missed ITC for 2026-27 can still be handled until 30 November 2027 or the annual return date, whichever is earlier.
The checklist
| # | Task | By when | Why |
|---|---|---|---|
| 1 | Reconcile ITC in books with GSTR-2B and the Invoice Management System | March, then monthly | Credit not in 2B is generally not available; chase suppliers before they file their last returns |
| 2 | Reverse charge: pay tax and issue self-invoices for purchases from unregistered suppliers | Within 30 days of receipt (Rule 47A) | RCM tax is paid in cash and only then claimed as ITC |
| 3 | Credit notes for 2026-27 sales | By 30 November 2027 or annual return date | After that the output tax cannot be reduced |
| 4 | Missed ITC for 2026-27 | By 30 November 2027 or annual return date | Section 16(4) time limit |
| 5 | ITC on invoices unpaid for 180 days | Reverse in the return for the period | See ITC reversal at 180 days |
| 6 | LUT for 2027-28 | Before the first export or SEZ supply of the new year | Without it you must pay IGST and claim a refund |
| 7 | QRMP for April to June 2027 | Between 1 February and 30 April 2027 | Option for taxpayers with aggregate turnover up to ₹5 crore |
| 8 | New invoice series from 1 April | Before the first invoice of the year | Serial numbers must be unique for each financial year |
| 9 | E-invoice threshold check | Close of the year | Crossing ₹5 crore makes e-invoicing mandatory from the next year |
Reconciling ITC and handling credit notes
Download GSTR-2B for each month of the year and match it, supplier by supplier, against your purchase register. Three kinds of difference matter: invoices in your books but missing from 2B (the supplier has not filed or used the wrong GSTIN), invoices in 2B but not in your books (possible fake or wrong billing to your GSTIN), and amount mismatches. Write to suppliers in March; they can still correct before their annual cut-off. Check each supplier's GSTIN status on FundRaksha Trust before you rely on the credit.
For credit notes, agree the discounts, rate differences and returns with each buyer before year-end and issue the credit notes promptly. The buyer must deal with the matching ITC on its side. See credit note for how it works.
Worked example (hypothetical)
A Rajkot engineering trader with turnover of ₹4.6 crore in 2026-27 finds ITC of ₹4,82,000 in its books but only ₹4,61,500 in GSTR-2B. The ₹20,500 gap is three invoices: ₹12,600 from a supplier who has not filed March GSTR-1, ₹5,400 billed to a branch GSTIN by mistake, and ₹2,500 of a rate difference. The trader writes to all three in the first week of April. The supplier files, the wrong-GSTIN invoice is re-issued, and the rate difference is settled by a debit note, so the full ₹20,500 is in 2B well before 30 November 2027.
Its turnover is below ₹5 crore, so e-invoicing is not yet mandatory and QRMP remains an option. If 2027-28 turnover crosses ₹5 crore, e-invoicing will apply from 1 April 2028. Use the e-invoice limit checker to test your own numbers.
Invoice series, e-invoice and QRMP: the April switches
- Invoice series: start a fresh series, for example RJ/27-28/0001. Keep it to 16 characters with letters, numbers, hyphen or slash, and one series per branch or business line if you need more.
- E-invoice: the test is aggregate turnover across all GSTINs on your PAN in any financial year since 2017-18. Once you cross ₹5 crore, B2B invoices, export invoices and B2B credit and debit notes need an IRN. Businesses with aggregate turnover of ₹10 crore or more must also report each invoice to the IRP within 30 days of its date.
- QRMP: choose by 30 April for April to June. You then file GSTR-1 and GSTR-3B quarterly and pay tax monthly.
- Annual return: GSTR-9 for 2026-27 is due by 31 December 2027; for businesses up to ₹2 crore turnover it has been optional in recent years under a yearly notification, so check before you skip it.
If you bill on FundRaksha Book, its sales and GST reports help you tie your outward supplies back to GSTR-1. Book does not generate e-invoices, e-way bills or GST return files, so keep using the government portals for those. Work out tax on any line with the GST calculator.
Sources
Last reviewed: 2026-10-21. Information for Indian businesses; not legal advice.