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GST Hisab

GST Interest Calculator

Paid GST after the due date? Put in the cash amount and two dates. You get the interest at 18% a year, to the paisa.

GST Interest Calculator

Interest on

Only the part paid from the electronic cash ledger (Rule 88B(1)). Tax set off from ITC carries no interest.

GSTR-3B: 20th of next month (monthly filers)

Rate: 18% per year (Section 50). Formula: amount × 18% × days ÷ 365.

Result

Enter the amount and both dates to see the interest.

Pay interest head-wise (CGST, SGST, IGST) in cash, in Table 5.1 of GSTR-3B. The portal also auto-computes it; use this to check.

How GST interest is worked out

Section 50(1) of the CGST Act charges interest when tax reaches the government late. The rate notified is 18% a year. It is simple interest, counted for each day from the day after the due date up to the day you pay.

Interest = Tax paid in cash × 18% × days late ÷ 365

The GST portal uses the same formula in its own GSTR-3B interest computation, so the two numbers should match.

Only the cash part attracts interest

This is where most people overpay in their head. Since Rule 88B (Notification 14/2022-CT, effective from 1 July 2017), interest on a late return is charged only on the portion paid from the electronic cash ledger. Tax you set off using input tax credit is not counted.

Say a Pune trader owes ₹2,40,000 of GST for September 2026 and has ₹1,40,000 of ITC. The cash part is ₹1,00,000. He files GSTR-3B on 19 November instead of the due date, 20 October, which is 30 days late. Interest = 1,00,000 × 18% × 30 ÷ 365 = ₹1,479.45. Not ₹3,550 on the full ₹2,40,000.

There is one more relief. If you had already deposited cash in the ledger on or before the due date and it stayed there until you filed, that amount is ignored for interest (proviso added by Notification 12/2024-CT).

Interest on wrongly used ITC

Section 50(3) covers input tax credit that was wrongly availed and used. Credit that was claimed but is still sitting unused in your ledger carries no interest. The rate here is also 18% a year, from the date of utilisation until you reverse it or pay the tax. Rule 88B(3) explains when credit counts as "used": when your credit ledger balance falls below the wrong amount.

Interest vs late fee

They are two separate charges. Interest is for paying tax late. Late fee is for filing the return late, even a nil return. A late GSTR-3B usually means both. Work out the second one with our GST late fee calculator.

FAQs

What is the interest rate on late GST payment?
18% per year, simple interest, under Section 50(1) of the CGST Act. It is counted for every day of delay from the day after the due date.
Is GST interest charged on the full tax or only cash?
On a late return, only on the tax paid from the electronic cash ledger (Rule 88B(1)). Tax set off from input tax credit does not attract interest.
How many days do I count?
From the day after the due date up to and including the day you pay. GSTR-3B due on 20 October and paid on 19 November is 30 days late.
Can I pay GST interest from ITC?
No. Interest has to be paid in cash, head-wise (CGST, SGST/UTGST, IGST), through GSTR-3B Table 5.1 or a DRC-03.
Is interest on wrongly claimed ITC 24%?
The Act allows up to 24%, but the notified rate under Section 50(3) is 18% a year, and only once the wrong credit is actually used.

Sources: Section 50, CGST Act 2017; Rule 88B, CGST Rules (CBIC tax information portal). This tool gives an estimate; for a notice or demand, check with your CA.

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