Delayed reported invoice in GSTR1

Record the original Sales invoice in October 2025 (F8) to maintain accurate FY 25-26 financial statements. Accept the resulting mismatch in Tally's October GST reports, as the physical reporting has already been handled on the portal for June 2026. Finally, pass a separate payment/journal entry in June/July 2026 to account for the mandatory 18% interest on the delayed GST payment.

If you are non corporate entity, then as per accounting standerd 5 , you can show it as a prior period Income separately in Profit & Loss Account.as a Income 

So in Tally prime Gateway of Tally / Voucher/ Sales , you pass entry 

Trade Debtors A/c Dr

To prior period Sales A/c Cr 

To Out put CGST A/c Cr 

To Out put SGST  A/c Cr 

Narration ( prior period sales) 

If you are Non corporate entities then Indian Accounting Standard 8 will applicable, but almost same reporting 

If you are Non corporate entities then you to follow INDAS 8 ,It is  not similar to Accounting Standards 5 . So refer and apply for prior period Income. 

please correct my secod reply instead of  " Non Corporate entity " , you read it as " Corporate entity " ( INDAS 8 )

Two things to handle separately here: the Tally entry and the interest exposure. TallyPrime entry: Create the sales voucher in TallyPrime using the original invoice date (October 2025), not June 2026. This ensures the transaction posts to the correct financial year and books. The GST ledger entry will flow to October 2025 period. If you need to keep a note of when it was actually reported, use the Narration field. GST compliance position: When the invoice was reported in June 2026 GSTR-1, the output tax liability for October 2025 was declared late. If the corresponding GST was not paid in the October 2025 GSTR-3B, interest at 18% per annum applies from the original due date (November 20, 2025) to the date the tax was actually deposited. Check your October 2025 GSTR-3B to confirm whether the output tax for this invoice was already included , sometimes the tax was paid correctly but the invoice just missed GSTR-1 reporting. If the tax was paid on time in GSTR-3B and only the invoice was missed in GSTR-1, the interest exposure is minimal and the late GSTR-1 reporting in June 2026 covers the disclosure. If the tax itself was unpaid from October 2025, compute and pay the interest along with the next GSTR-3B filing. For the full GSTR-1 amendment and late invoice workflow, this [step-by-step GSTR-1 filing guide](https://taxgarden.in/blog/gst-login-gstr-1-filing-step-by-step-guide-2026) covers the amendment table and how to handle previously missed invoices.

My reply is  considering no sales entry has been pass in the books accounts ( omitted) in OCT 2025 and also omitted to report GSTR1 and GSTR3B in Oct 25 and therefore you have to report in Current year P& L as a prior period Income as per accounting standards.