GST Invoice Management System (IMS): Complete Guide for 2026
If you file GST returns, IMS now affects every invoice your supplier uploads. From April 1, 2026, the GST Invoice Management System (IMS) became mandatory on the GST portal. That means the portal can block your ITC claim if you don't handle invoices correctly inside IMS.
Most businesses are either ignoring it or doing it wrong. Both outcomes cost money.
This guide explains what IMS is, what the three actions mean, how it connects to GSTR-2B, and the mistakes to avoid. The information here comes from working directly with GST registration cases and client compliance queries at gstregistration.co -not from secondhand sources.
What Is GST IMS?
IMS is a dashboard on the GST portal where you review invoices your suppliers have filed. Before IMS, every supplier invoice automatically showed up in your GSTR-2B as available ITC -whether the underlying tax was paid or not. That gap allowed fake ITC claims on a large scale.
IMS fixes this. Now, only invoices you accept (or don't reject) flow into your GSTR-2B as eligible ITC. You get to check each invoice before it becomes part of your ITC claim.
What is GST IMS?
GST Invoice Management System (IMS) is a feature on the GST portal where recipient taxpayers can accept, reject, or keep pending each invoice filed by their supplier in GSTR-1, GSTR-1A, or IFF. Only accepted records flow into GSTR-2B as eligible Input Tax Credit (ITC).
IMS Timeline -How It Got Here
-
October 1, 2024: IMS went live on GST portal (read-only mode)
-
October 14, 2024: Taxpayers could start accepting/rejecting invoices
-
November 14, 2024: First GSTR-2B generated using IMS actions
-
October 2025: Section 38 of CGST Act amended -ITC now legally tied to IMS-accepted records
-
April 1, 2026: IMS became fully mandatory. Hard ITC blocks now enforced on the portal
-
April 21, 2026: GSTN released Excel offline tool for bulk IMS actions
Source: GSTN official advisory, CBIC Circular No. 230/24/2024-GST
How Does GST Invoice Management System Work?
When your supplier files their GSTR-1 or IFF, every B2B invoice they upload shows up in your IMS dashboard. You have three options for each record.
The Three Actions
Accept -The invoice is correct. ITC flows into GSTR-2B as eligible credit. This is also the default if you take no action before GSTR-2B generates on the 14th.
Reject -Invoice has errors, wrong GSTIN, or is not your supply. ITC does not flow into GSTR-2B. If you reject a credit note, it also increases your supplier's tax liability in the next GSTR-3B under Rule 67B.
Pending -You need more time to verify with your supplier. The record does not enter GSTR-2B for that period. From October 2025, credit notes and downward amendments can only stay pending for one tax period.
What is Deemed Acceptance in IMS?
If you take no action on an invoice in IMS before GSTR-2B generates on the 14th, the system treats it as accepted. The invoice enters your GSTR-2B as eligible ITC automatically. You are still responsible for verifying it is a valid claim before filing GSTR-3B.
How IMS Connects to GSTR-2B and GSTR-3B
GSTR-2B is generated on the 14th based on your IMS actions up to that date. You can still take actions in IMS after the 14th -up until you file GSTR-3B. But if you act after the 14th, you must click 'Recompute GSTR-2B' on the portal. Otherwise the old draft stays and your ITC figures are wrong.
Once GSTR-3B is filed, that period is locked. Any invoice you rejected cannot be undone for that month.
Two rules the portal now enforces: GSTR-2B for a period only generates after GSTR-3B for the prior period is filed. And if an original invoice and its amendment fall in different GSTR-2B periods, you must act on the original first.
Need help with GST Return Filing? Our team at gstregistration.co/gst-return-filing.aspx handles GSTR-3B and all return filing -so your IMS actions and ITC claims stay perfectly aligned.
How to Use IMS on the GST Portal -Step by Step
-
Log in at www.gst.gov.in with your GSTIN and password.
-
Go to: Services > Returns > Invoice Management System (IMS).
-
Click on Inward Supplies to see invoices from your suppliers.
-
Records are grouped by type: B2B Invoices, Credit Notes, Debit Notes, Amendments.
-
Check each invoice against your purchase register or books.
-
Select Accept, Reject, or Pending for each record.
-
Use bulk actions to handle multiple invoices at once if needed.
-
Click Save after selecting actions.
-
If you act on any invoice after the 14th, click 'Recompute GSTR-2B.'
-
Proceed to file GSTR-3B using the updated GSTR-2B data.
IMS Offline Excel Tool
GSTN released an MS Excel-based offline IMS tool on April 21, 2026. You can download your IMS data, mark accept/reject/pending actions offline in the spreadsheet, then upload back to the portal. This works well for businesses with large monthly invoice volumes.
What to Check Before Taking Any Action
-
Invoice amount in IMS matches your purchase records
-
Supplier GSTIN is correct
-
Invoice date falls in the right tax period
-
For credit notes -original invoice amount and credit amount are accurate
-
If something looks off, mark as Pending and ask your supplier to amend via GSTR-1A
What Records Appear in IMS -and What Don't
Records That Appear
-
B2B invoices from GSTR-1 or IFF
-
Credit notes issued by suppliers
-
Debit notes from GSTR-1
-
Amendments through GSTR-1A
-
Bill of Entry for import of goods (added October 2025)
-
Import of goods from SEZ units
Records That Do NOT Appear in IMS
-
IGST paid on imports (flows directly to GSTR-2B)
-
RCM supplies from unregistered persons under Section 9(4)
-
ISD-distributed invoices
-
Supplies from composition scheme taxpayers
Composition scheme taxpayers cannot claim ITC, so IMS does not apply to them at all.
IMS for QRMP Taxpayers
QRMP taxpayers see invoices in IMS every month, but their GSTR-2B generates quarterly. They must review IMS monthly but file GSTR-3B quarterly. The one-tax-period pending limit for credit notes applies quarterly for QRMP -not monthly.
Got a GST Notice related to ITC mismatch? Don't ignore it. Visit gstregistration.co/gst-notices.aspx to understand your options and get expert help before deadlines pass.
5 IMS Mistakes That Are Causing ITC Problems Right Now
These come up repeatedly when businesses come to us with ITC mismatch issues.
1. Rejecting invoices to 'clean up' the dashboard.
Rejection permanently blocks ITC for that period. Rejecting a credit note also increases your supplier's output liability under Rule 67B. Use Reject only when the invoice is genuinely wrong or not yours.
2. Acting on an amendment before acting on the original.
When the original and its amendment fall in different GSTR-2B periods, the portal silently blocks the second action. ITC reconciliation breaks. Always act on the original record first.
3. Skipping the 'Recompute GSTR-2B' step.
Any action taken on or after the 14th does not update GSTR-2B automatically. You must click Recompute. Filing GSTR-3B with the old draft means wrong ITC numbers -and a potential filing block under the Zero Mismatch Policy.
4. Relying entirely on deemed acceptance.
Deemed acceptance lets every unreviewed invoice into your GSTR-2B -including fraudulent ones. If you get a scrutiny notice, you are responsible for every record in your GSTR-2B, whether you reviewed it or not.
5. Leaving credit notes on Pending too long.
Since October 2025, credit notes can only be kept pending for one tax period. After that, the system auto-accepts them. If you miss this, ITC gets credited when you did not intend it to.
The Legal Side -Why IMS Matters More Than Most Businesses Realize
In October 2025, Section 38 of the CGST Act was amended. ITC is now legally tied to records accepted in IMS -not just a portal workflow. That is a material change.
Before the amendment, ITC eligibility was primarily governed by Section 16 conditions. After, your IMS action history on the portal is the statutory evidence of your entitlement. A wrong rejection is not just an operational mistake -it has legal consequences for both you and your supplier.
From April 2026, the portal also enforces a Zero Mismatch Policy: GSTR-3B filing is blocked if ITC claimed exceeds what is in GSTR-2B. IMS is where that starts.
From ground-level work at gstregistration.co: The confusion we see most often is businesses treating IMS as optional housekeeping. It is not, since October 2025. The portal will not let you file GSTR-3B with ITC that is not in GSTR-2B, and GSTR-2B is directly driven by what you do in IMS. Getting IMS right is now the same as getting your ITC right.
Still not registered under GST? Every day without registration means missed ITC claims and compliance risk. Get your GST number quickly at gstregistration.co -document preparation to ARN tracking, handled by the same team that works with GST cases daily.
GST IMS -Common Questions
Q1. Is IMS mandatory for all GST-registered taxpayers?
Yes, from April 1, 2026. Composition scheme taxpayers are excluded since they do not claim ITC.
Q2. What happens if I take no action in IMS?
Those invoices are treated as deemed accepted when GSTR-2B generates on the 14th. They enter your GSTR-2B as available ITC. You are still responsible for the accuracy of every claim.
Q3. Can I undo a rejection after GSTR-3B is filed?
No. Once GSTR-3B is filed, rejections for that period are permanent. The supplier needs to issue a fresh invoice for it to appear in a future month's IMS.
Q4. My supplier filed a wrong invoice amount. What do I do?
Mark it as Pending and contact your supplier immediately. Ask them to amend using GSTR-1A before the 14th. If GSTR-2B has already generated, the amendment will appear in next month's IMS.
Q5. Can I handle IMS in bulk?
Yes. The portal supports bulk select-and-act. The Excel offline tool released in April 2026 makes it easier -download IMS data, take actions offline, upload back to the portal.
Q6. What is the difference between IMS and GSTR-2B?
IMS is where you review and act on invoices. GSTR-2B is the output -it only shows invoices you accepted. GSTR-2B then feeds into GSTR-3B for your ITC claim.
Q7. Does IMS apply to QRMP taxpayers?
Yes. They see invoices monthly but GSTR-2B generates quarterly. The pending limit for credit notes applies per quarter for QRMP, not per month.
