GST RE-COMPUTE INTEREST Button: How to Correct Interest Liability

The GST Re-Compute Interest button is a new feature on the GSTN portal (www.gst.gov.in) that allows taxpayers to recalculate their interest liability under Section 50 of the CGST Act, 2017 directly within the GSTR-3B filing interface. Launched in April 2026, this tool replaces the earlier manual computation method where taxpayers had to calculate interest offline and self-assess the amount before filing. The button applies Rule 88B of the CGST Rules to compute interest on net tax liability at 18% per annum for delayed payments or 24% per annum for excess ITC utilisation, calculated on a daily basis from the due date until actual payment.

What Changed: The Re-Compute Interest Button Update

Before this update, GST taxpayers had to manually calculate interest on delayed payments using offline spreadsheets or third-party tools. The GSTN portal auto-populated an interest figure in GSTR-3B, but this amount was frequently inaccurate because the system did not always account for electronic credit ledger balances available on the due date. Taxpayers either overpaid interest (and then struggled with refund applications) or underpaid it (triggering demand notices from jurisdictional officers under Section 73 of the CGST Act).

The new Re-Compute Interest button solves this by pulling real-time data from three sources: your electronic cash ledger balance as of the due date, your electronic credit ledger balance, and the actual GSTR-3B liability for the period. The computation follows the net tax liability method mandated by Rule 88B of the CGST Rules (inserted vide Notification No. 14/2022-CT dated 5th July 2022, effective retrospectively from 1st September 2022). This means interest applies only on the amount that could not have been paid using available ITC on the due date.

Key Differences from the Previous System

Who is Affected: Impact Assessment

The Re-Compute Interest button impacts every GST-registered taxpayer who has filed or will file GSTR-3B with a delayed payment component. Based on GSTN data published in their April 2026 advisory, over 1.4 crore active GSTINs file GSTR-3B returns monthly or quarterly. Of these, an estimated 15-20% file after the due date in any given month, making them liable for interest under Section 50.

Taxpayer Categories Directly Affected

• Regular Monthly Filers: Taxpayers with aggregate turnover above Rs. 5 crore who file GSTR-3B by the 20th of the following month. Any delay triggers interest computation via the button.
• QRMP Scheme Taxpayers: Quarterly filers with turnover up to Rs. 5 crore. Monthly tax payments through PMT-06 by the 25th are tracked, and the button calculates interest for shortfalls.
• Composition Scheme Dealers: Filing CMP-08 quarterly with payment due by the 18th of the month following the quarter. The button now covers their interest computation from June 2026.
• Taxpayers with Pending Past-Period Returns: Those filing belated returns for earlier periods (FY 2023-24, FY 2024-25) where interest has accumulated over extended delays.
• ITC Reversal Cases: Businesses that reversed ITC under Rule 42 or Rule 43, increasing their net liability retrospectively and triggering interest for past periods.

Legal Basis: Section 50 of the CGST Act, 2017

Section 50 of the Central Goods and Services Tax Act, 2017 is the governing provision for interest on delayed payment of GST. It establishes the legal framework that the Re-Compute Interest button operationalises on the portal. Understanding the specific sub-sections helps taxpayers verify whether the portal calculation aligns with the law.

Section 50(1): Interest on Delayed Tax Payment

Every person liable to pay tax under the CGST Act who fails to pay the tax or any part thereof to the Government within the prescribed period shall, on their own, pay interest at the rate notified by the Government (currently 18% per annum). The key phrase is "on his own motion" - meaning self-assessment of interest is legally mandatory even without a notice from the department. The Re-Compute button now automates this self-assessment obligation, ensuring no taxpayer inadvertently violates Section 50(1) by failing to compute interest.

Section 50(3): Interest on Excess ITC Utilisation

Where a taxpayer claims ITC to which they are not entitled and uses it to discharge output tax liability, interest at 24% per annum applies on the amount of ineligible ITC utilised. This higher rate acts as a deterrent against fraudulent ITC claims. The Re-Compute button identifies excess ITC situations by cross-referencing GSTR-2B auto-drafted ITC with the actual claims made in GSTR-3B Table 4. If the claimed amount exceeds the eligible amount, the system flags the differential and applies the 24% rate.

Rule 88B: Net Liability Method (Post-September 2022)

Rule 88B inserted into the CGST Rules vide Notification No. 14/2022-CT specifies that interest under Section 50(1) shall be calculated on the portion of tax that remains unpaid after considering the balance in the electronic credit ledger and electronic cash ledger as on the due date. This retrospective amendment resolved the long-standing controversy of whether interest should apply on gross or net liability. The Re-Compute button implements Rule 88B by default, pulling your ledger balances as of the 20th (or applicable due date) of the relevant month.

Interest Rate Table: When 18% and 24% Apply

The Re-Compute Interest button applies two distinct interest rates based on the nature of the tax shortfall. Here is the complete breakdown of scenarios, applicable rates, and the governing provisions that the portal references during computation.

Step-by-Step: How to Use the Re-Compute Interest Button

Follow these steps to use the Re-Compute Interest button on the GST portal. The entire process takes under 5 minutes for a single return period. Make sure you have your login credentials and have verified your electronic ledger balances before starting.

1. Log in to the GST Portal: Visit www.gst.gov.in and log in using your GSTIN, username, and password. Complete the captcha verification. If you face login issues, clear browser cache or try an incognito window.
2. Navigate to GSTR-3B: Go to Services > Returns > Returns Dashboard. Select the financial year and return filing period (month) for which you need to compute interest. Click on "Prepare Online" for the GSTR-3B return.
3. Review Tax Liability Section: Scroll to Table 6.1 (Payment of Tax) in the GSTR-3B form. The portal displays your tax liability for IGST, CGST, SGST, and Cess. Verify these figures match your GSTR-1 summary and GSTR-2B reconciliation.
4. Locate the Re-Compute Interest Button: Below the tax payment table, you will see the "Interest" column with an auto-populated figure. Next to this figure, the blue "Re-Compute Interest" button appears. This button is active only when the filing date is past the due date.
5. Click Re-Compute Interest: Click the button. The portal processes the calculation for 2-3 seconds. A computation summary popup appears showing: due date, actual filing/payment date, number of delay days, net tax liability considered, ITC deducted (per Rule 88B), and the final interest amount for each tax head.
6. Review the Computation Summary: Verify the displayed figures against your records. Check that the "ITC available on due date" matches your electronic credit ledger statement for that date. If the number of delay days seems incorrect, verify your return filing history under Track Return Status.
7. Accept or Override: If the computed interest is correct, click "Accept" to update the interest field in your GSTR-3B. If you believe the calculation is wrong (for example, due to a system error in ledger balance), you can manually override the amount - but you must provide a reason in the text box that appears.
8. Download Computation PDF: Click the "Download Computation" link to save a PDF showing the full calculation methodology. Keep this document for your records. It serves as evidence if the department questions your interest payment during assessment.
9. Complete Return Filing: After accepting the interest amount, proceed with the rest of your GSTR-3B filing. The interest amount is automatically added to your total payment liability. Pay through the electronic cash ledger (interest cannot be paid using ITC).
10. Verify Payment in Electronic Liability Register: After filing, check your Electronic Liability Register (Services > Ledgers > Electronic Liability Register) to confirm the interest payment is recorded. The register should show zero outstanding for the period.

For taxpayers who need support with GSTR-3B reconciliation and interest computation, GST return filing assistance is available. Professional charges start at Rs. 1,499 per month (government fees charged separately at actuals).

Scenarios Where Re-Computation Applies

The Re-Compute Interest button is not a one-size-fits-all feature. Its utility varies based on the taxpayer's specific situation. Here are the primary scenarios where the button provides corrected interest figures that differ from the portal's default auto-populated amount.

Scenario 1: Late Filing with Sufficient ITC Balance

A taxpayer with Rs. 5,00,000 gross CGST liability files GSTR-3B 15 days late. Their electronic credit ledger showed Rs. 4,50,000 ITC balance on the due date. Under the old system, the portal might calculate interest on the full Rs. 5,00,000 (gross basis). The Re-Compute button correctly applies Rule 88B and calculates interest only on Rs. 50,000 (net liability after deducting available ITC). The interest drops from Rs. 3,699 to just Rs. 370 for the period.

Scenario 2: Excess ITC Claimed in a Previous Period

A taxpayer claimed Rs. 2,00,000 ITC in January 2026 that was later found ineligible (supplier did not file GSTR-1, so ITC disappeared from GSTR-2B in February). The taxpayer reversed this ITC in their March 2026 GSTR-3B. The Re-Compute button calculates 24% interest under Section 50(3) on the Rs. 2,00,000 from January 20th (original due date) to March 20th (reversal date), totalling Rs. 7,890 instead of the manually estimated Rs. 6,575 that many taxpayers compute by approximating months instead of exact days.

Scenario 3: Partial Tax Payment Through PMT-06

A QRMP scheme taxpayer deposits Rs. 80,000 through PMT-06 for Month 1 of the quarter, but the actual liability for that month was Rs. 1,20,000. The Re-Compute button identifies the Rs. 40,000 shortfall and calculates 18% interest from the 26th of the following month (PMT-06 due date + 1) until the quarterly return filing date. This granular monthly tracking was previously impossible without manual records.

Scenario 4: Amendment to Earlier Period Data

When a taxpayer amends sales data for October 2025 in their January 2026 GSTR-1 (increasing output liability), the additional tax must be paid in the January GSTR-3B. If January GSTR-3B is filed on time but the additional liability was technically due in November 2025, the Re-Compute button calculates interest from November 20, 2025, for the differential amount. This cross-period computation is where the button provides the most value.

Feature Rollout Timeline

The GSTN implemented the Re-Compute Interest button in a phased manner to ensure system stability and address taxpayer feedback at each stage. Here is the complete timeline from announcement to full deployment.

Error Resolution: Common Portal Issues and Fixes

While the Re-Compute Interest button works correctly for most taxpayers, portal glitches and data synchronisation delays can cause errors. Here are the most frequently reported issues and their resolutions, based on GSTN helpdesk data and common user reports from the first two months of the feature's availability.

Error 1: "Unable to Fetch Ledger Balance" Message

This error occurs when the GSTN server cannot retrieve your electronic credit or cash ledger balance for the specified due date. The most common cause is server timeout during peak filing hours (typically the 18th-20th of each month). Resolution: Try again during off-peak hours (early morning or late evening). If the error persists for more than 24 hours, raise a ticket at the GST self-service portal (selfservice.gstsystem.in) with your GSTIN and the specific return period affected.

Error 2: Interest Showing as Zero Despite Late Filing

If the button shows zero interest even though you filed after the due date, check whether your entire tax liability was already available in the electronic cash ledger or credit ledger on the due date. Under Rule 88B, if the funds were available to pay the full liability on time (even though the return was not filed), interest may genuinely be zero. Verify by downloading your ledger statement for the due date. If the ledger shows insufficient balance and interest is still zero, this is a system error. Report it through the grievance mechanism.

Error 3: Incorrect Number of Delay Days

The portal sometimes counts delay days incorrectly when a return period's due date falls on a public holiday or Sunday and GSTN extended the deadline through a press release (rather than a formal notification). The system may not have updated the extended due date. In such cases, override the interest amount manually and attach the GSTN press release reference in the reason field. Download the computation PDF before overriding for your records.

Error 4: Button Not Visible on the Return Page

If the Re-Compute Interest button does not appear, confirm that: (a) you are using a supported browser (Chrome 90+, Firefox 88+, or Edge 90+); (b) the return period you selected is not already filed; (c) your taxpayer category is covered under the current rollout phase (check the timeline table above). Composition dealers gained access only from June 2026, and taxpayers migrated from older state VAT systems may need to update their registration profile.

Error 5: Mismatch Between Re-Computed and Auto-Populated Interest

The auto-populated interest (shown before you click Re-Compute) uses a simplified calculation that may not account for Rule 88B adjustments. The Re-Compute button provides the accurate figure. If there is a mismatch, always rely on the Re-Computed figure. The older auto-populated amount is a legacy system estimate. GSTN has confirmed in Advisory No. 632/2026 that the Re-Compute calculation is the authoritative figure for assessment purposes.

Action Items for Taxpayers

With the Re-Compute Interest button now fully operational, taxpayers should take specific actions to ensure compliance and avoid unnecessary interest charges. These steps apply regardless of your filing frequency or turnover category.

Immediate Actions (Complete Within 7 Days)

1. Audit Pending Returns: Log in to the GST portal and check Services > Returns > Track Return Status. Identify all unfiled GSTR-3B returns. For each pending return, the interest clock is running daily at 18% per annum.
2. Verify Ledger Balances: Download your Electronic Credit Ledger and Electronic Cash Ledger statements for the last 12 months. Cross-reference these balances against your GSTR-3B filings to identify any periods where you may have overpaid or underpaid interest.
3. Update Browser and System: Ensure your filing computer uses Chrome 90+ or Firefox 88+. Clear browser cache and cookies for gst.gov.in to prevent interface glitches with the new Re-Compute button.

Monthly Ongoing Actions

1. File Before the Due Date: The simplest way to avoid interest is timely filing. Regular filers must file GSTR-3B by the 20th of the following month. QRMP taxpayers must deposit PMT-06 by the 25th.
2. Use Re-Compute Before Accepting Auto-Populated Interest: Never accept the default auto-populated interest without clicking Re-Compute first. The difference can range from a few hundred to tens of thousands of rupees depending on your ITC position.
3. Download and Archive Computation PDFs: After every Re-Computation, download the PDF summary. Store these documents for at least 7 years (the maximum period under Section 73/74 for demand notices) as evidence of correct interest calculation.
4. Reconcile ITC Monthly: Compare your GSTR-2B auto-drafted ITC with your purchase register. Claim only eligible ITC to avoid triggering the 24% interest rate under Section 50(3) during subsequent audits.

If you receive a demand notice for interest under Section 73 or 74, GST notice reply assistance can help with drafting responses and compiling documentation. Professional charges vary based on notice complexity (government fees separate).

Interest Calculation Methodology: A Worked Example

Understanding the exact calculation methodology helps you verify the Re-Compute button's output against your own records. Here is a detailed worked example covering the most common scenario (late filing with partial ITC availability) with step-by-step computation.

Example: Monthly Filer with Mixed Liability

Consider a taxpayer with the following data for March 2026 (due date: April 20, 2026; actual filing date: May 5, 2026; delay: 15 days):

• Gross CGST Liability: Rs. 3,00,000
• Gross SGST Liability: Rs. 3,00,000
• IGST Liability: Rs. 0
• Electronic Credit Ledger (CGST) on April 20: Rs. 2,20,000
• Electronic Credit Ledger (SGST) on April 20: Rs. 2,50,000
• Electronic Cash Ledger Balance on April 20: Rs. 0

Step 1: Calculate Net CGST Liability

Net CGST = Gross CGST - ITC available on due date = Rs. 3,00,000 - Rs. 2,20,000 = Rs. 80,000

Step 2: Calculate Net SGST Liability

Net SGST = Gross SGST - ITC available on due date = Rs. 3,00,000 - Rs. 2,50,000 = Rs. 50,000

Step 3: Compute Interest on CGST

Interest (CGST) = Rs. 80,000 x 18% x (15/365) = Rs. 80,000 x 0.18 x 0.0411 = Rs. 592

Step 4: Compute Interest on SGST

Interest (SGST) = Rs. 50,000 x 18% x (15/365) = Rs. 50,000 x 0.18 x 0.0411 = Rs. 370

Step 5: Total Interest Payable

Total Interest = Rs. 592 + Rs. 370 = Rs. 962

Without the Re-Compute button (using gross liability method), the interest would have been: (Rs. 3,00,000 + Rs. 3,00,000) x 18% x (15/365) = Rs. 4,438. The Rule 88B-compliant Re-Compute button saves this taxpayer Rs. 3,476 in a single return period.

Amnesty and Waiver Provisions for GST Interest

The GST Council periodically announces amnesty schemes that reduce or waive interest and late fees for delayed filings. These waivers operate under Section 128 of the CGST Act, 2017, which grants the Government authority to waive interest or penalties for a specified class of taxpayers. The Re-Compute button automatically applies active waiver notifications to your calculation if your return period falls within the waiver scope.

Active and Recent Waiver Schemes

• Amnesty Scheme 2026 (Notification No. 02/2026-CT): Waives late fees exceeding Rs. 500 per return for GSTR-3B filings of FY 2022-23 and earlier, filed between April 1, 2026, and September 30, 2026. Interest is reduced to 9% (from 18%) for returns filed during this window.
• COVID-19 Relief Extensions: Extended deadlines for March 2020 to August 2020 returns. The Re-Compute button correctly identifies these extended due dates and does not charge interest for periods covered by the extension notifications.
• Natural Disaster Provisions: Under Section 168A of the CGST Act, due dates are extended for taxpayers in notified disaster-affected areas. The button applies these extensions when your registered address falls within the notified district.

Before filing old returns, always check the latest notifications at www.cbic.gov.in and verify whether your period qualifies for reduced interest. The GST Amnesty Scheme 2026 guide covers eligibility criteria and the application process in detail.

Integration with Other GST Portal Features

The Re-Compute Interest button does not operate in isolation. It connects with multiple existing portal features to provide a cohesive filing experience. Understanding these integrations helps you use the feature more effectively and troubleshoot issues faster.

Electronic Ledger Integration

The button pulls real-time balances from three ledgers maintained on the GST portal. The Electronic Credit Ledger (reflecting ITC from GSTR-2B), the Electronic Cash Ledger (reflecting challan deposits via PMT-06), and the Electronic Liability Register (reflecting all tax, interest, penalty, and fee demands). When you click Re-Compute, the system queries each ledger's balance as of the specific due date for the return period, not the current balance. This historical lookup is what makes the computation accurate under Rule 88B.

GSTR-2B Reconciliation Link

For Section 50(3) computations (24% interest on excess ITC), the button cross-references your GSTR-3B ITC claims against GSTR-2B auto-drafted credits for the same period. Any excess claim triggers the higher interest rate. This is why monthly reconciliation between your purchase register, GSTR-2B, and GSTR-3B Table 4 is critical. The GSTR-3B filing guide covers this reconciliation process step by step.

Annual Return (GSTR-9) Connection

Starting July 2026, the Re-Compute button will integrate with GSTR-9 (annual return) filing. This means if you paid excess interest during the year (across monthly returns), the annual return will show a consolidated interest reconciliation. Any overpayment identified during GSTR-9 filing can be claimed as a refund directly from the annual return interface, without requiring a separate RFD-01 application.

E-Way Bill System

Outstanding interest demands (where the Re-Compute button shows payable interest that remains unpaid) can block e-way bill generation once the demand is confirmed under Section 79. The GST portal shares demand data with the e-way bill system at ewaybillgst.gov.in. Settling interest promptly after re-computation ensures uninterrupted goods movement for your business. For businesses with frequent shipments, set up the Ship-to GSTIN compliance correctly to avoid additional complications.

For businesses needing ongoing support with GSTR-1, GSTR-3B, GSTR-9, and ITC reconciliation, GST compliance assistance plans start from Rs. 4,999 per quarter (government fees at actuals).

Common Mistakes to Avoid When Using Re-Compute Interest

Even with automated computation, taxpayers make errors that lead to incorrect interest payments. These mistakes are typically procedural rather than computational. Here are the top mistakes observed in the first two months since the button's launch, along with preventive measures.

1. Accepting Auto-Populated Interest Without Re-Computing: The auto-populated interest figure (displayed before clicking Re-Compute) uses an older calculation engine that may not apply Rule 88B correctly. Always click Re-Compute before accepting. The difference can be significant for taxpayers with high ITC balances.
2. Filing Returns Out of Sequence: If you have pending returns for multiple months, file them chronologically (oldest first). The Re-Compute button needs prior period data to calculate correctly. Filing out of sequence causes the system to use incorrect ledger balances, resulting in higher interest.
3. Ignoring the Computation PDF Download: The computation PDF is your primary evidence if the department disputes your interest payment. Once you move past the return filing screen, you cannot regenerate this PDF. Download it immediately after re-computation.
4. Manually Overriding Without Valid Reason: While the portal allows manual override, doing so without a valid, documented reason creates audit risk. The jurisdictional officer can question any manual reduction in interest during assessment. Only override when you have documentary proof of a system error.
5. Not Reconciling ITC Before Filing: If your GSTR-2B shows lower ITC than what you plan to claim in GSTR-3B, the excess claim triggers 24% interest under Section 50(3). Reconcile GSTR-2B with your purchase register before filing to avoid the higher interest rate.
6. Using Incorrect Return Period: Selecting the wrong month/quarter in the returns dashboard leads to interest computation for the wrong period. Double-check the period selection, especially during the first week of a new month when both current and previous period returns may be pending.

Related GST Portal Updates in 2026

The Re-Compute Interest button is part of a broader set of GSTN portal enhancements introduced in FY 2026-27. Understanding the full picture helps taxpayers plan their compliance strategy and take advantage of new features that reduce manual effort.

• Excel-Based Invoice Upload Tool: GSTN introduced a free Excel upload tool for GSTR-1 invoices, eliminating the need for third-party software for smaller businesses. This tool ensures accurate output liability computation, which directly affects interest calculations. Read the complete guide: GST Excel Invoice Upload Tool.
• GST Rate Overhaul: The GST rate restructuring in 2026 consolidated multiple rates into fewer slabs. Businesses transitioning between rate slabs must correctly compute liability at both old and new rates for the transition period. The Re-Compute button handles split-period calculations automatically.
• Mandatory Ship-to GSTIN Field: From June 15, 2026, the Ship-to GSTIN field is mandatory in e-invoices. This affects ITC eligibility for recipients and can impact interest calculations if ITC is denied due to incorrect ship-to details. See: Mandatory Ship-to GSTIN compliance.
• GSTR-9 Annual Return for FY 2025-26: The upcoming annual return filing (due December 31, 2026) will be the first to integrate with the Re-Compute button for consolidated interest reconciliation across all monthly returns of the financial year.

Taxpayers who proactively adopt these new tools and processes reduce their interest burden and compliance costs significantly. For businesses needing end-to-end support, GST return filing assistance covers all these aspects.

Summary

The GST Re-Compute Interest button on the GSTN portal (www.gst.gov.in) represents a significant improvement in how taxpayers calculate and pay interest under Section 50 of the CGST Act, 2017. By automatically applying Rule 88B's net liability method, considering electronic ledger balances as of the due date, and providing downloadable computation records, the feature eliminates the guesswork that previously led to overpayment, underpayment, and demand notice disputes. For taxpayers filing GSTR-3B monthly or quarterly, the immediate step is clear: always click Re-Compute before accepting any auto-populated interest figure. For those with pending returns, the cost of delay grows daily at 18% per annum, so filing immediately using the GSTR-9 return filing assistance or regular GSTR-3B filing support is recommended. The feature is fully live across all taxpayer categories as of June 2026.