Communication Between Tax Payer on GST Portal : What It Is, Why It Matters, and How to Use It

GST compliance is no longer limited to filing GSTR-1, GSTR-3B, GSTR-9 or reconciling ITC with GSTR-2B. The GST portal also provides a useful facility called “Communication Between Taxpayers.” In day-to-day practice, when a supplier uses this facility to send a message to his customer, it is often referred to as “Communication to Buyer” or “Communication to Recipient.”

This facility allows one registered taxpayer to communicate with another registered taxpayer through the GST portal itself. The purpose is to raise invoice-level issues, request action on documents reported or uploaded on the portal, send reminders, inform about missing documents, communicate payment status, and maintain a GST portal-based trail of communication between supplier and recipient. The official GST portal manual states that this functionality facilitates communication with the counterparty and enables a taxpayer to request action on documents reported or uploaded by either party through the portal.

Where is this option available?

-After logging into the GST portal, the taxpayer can access it through:

-Services > User Services > Communication Between Taxpayers

-The portal provides options such as Inbox, Compose, Outbox, and CSV template functionality. The Inbox shows notifications and replies received, Compose is used to send a new notification, and Outbox shows notifications and replies already sent.

Who can use this facility?

-This facility is available to registered persons under GST. However, it is not available to persons registered as TDS, TCS or Non-Resident Taxable Persons.

What is “Communication to Buyer”?

When a supplier sends a notification to his customer through this facility, the customer is treated as the Recipient. Therefore, from the supplier’s perspective, it becomes a communication to buyer.

For example, a supplier may use this feature when:

-Payment has not been received from the buyer.

-The buyer has asked for correction or clarification.

-There is a dispute regarding invoice, debit note or credit note.

-The supplier wants to create a GST portal-based record that payment is pending.

-The supplier wants to communicate any other GST document-related issue to the buyer.

The GST portal manual specifically provides an action option of “Payment not received” when a supplier sends a notification to a recipient taxpayer. This allows the supplier to inform the buyer that payment against the relevant document has not yet been received.

Why is it important?

-->This feature is important because GST compliance is heavily document-driven. Many disputes arise due to missing invoices, wrong GSTIN, wrong invoice value, incorrect tax rate, credit note mismatch, debit note mismatch, non-reporting in GSTR-1, ITC mismatch in GSTR-2B, or non-payment by buyer.

-->Earlier, most of these communications were done only through email, phone calls or WhatsApp. Those communications may still be useful, but they are outside the GST portal. The “Communication Between Taxpayers” functionality gives taxpayers an additional formal channel inside the GST system.

-->It does not replace accounting records, legal notice, recovery action, email follow-up or contractual documentation. However, it can support the taxpayer by creating a portal-based communication trail.

Connection with 180 days payment rule

-->One of the practical uses of communication to buyer is in cases where the buyer has not made payment within 180 days from the date of invoice.

-->Under Section 16(2) of the CGST Act, if the recipient fails to pay the supplier the value of supply along with tax within 180 days from the date of invoice, the recipient is required to pay back the ITC availed along with applicable interest. Once payment is made later, the recipient is entitled to re-avail the ITC.

-->Rule 37 of the CGST Rules further provides the mechanism for reversal of ITC in case of non-payment of consideration and also allows re-availment once payment is subsequently made.

-->Therefore, when a supplier uses the “Payment not received” option under communication to buyer, it may help establish that the buyer was informed through the GST portal. However, the supplier should understand that sending this communication does not automatically reverse the buyer’s ITC, does not automatically recover payment, and does not reduce the supplier’s GST liability. It is a communication and compliance-trail facility.

How to send communication to buyer on GST portal

The supplier can follow these steps:

Step 1: Login to GST portal

Login using the GSTIN credentials.

Step 2: Go to Communication Between Taxpayers

Navigate to:

Services > User Services > Communication Between Taxpayers

Step 3: Click on Compose

The Compose tab is used to send a new notification to a supplier or recipient.

Step 4: Select “Recipient”

Since the supplier is sending communication to the buyer, select Recipient in the “Notification To” field.

Step 5: Enter buyer GSTIN

Enter the GSTIN of the buyer. The trade name or legal name should get auto-populated after entering the GSTIN.

Step 6: Enter subject

Enter a short subject. As per the GST portal manual, the maximum length of the subject can be up to 50 characters.

Example subject:

Payment pending against invoice

Step 7: Select financial year, return period and form type

Select the relevant financial year, return period and form type. The portal provides form type options such as GSTR-1 and GSTR-3B.

Step 8: Add document details

Add the relevant invoice, debit note or credit note details. The portal works at document level, so the communication should be linked with the relevant document. The GST portal manual clarifies that for each document, the user needs to select the appropriate action required.

For communication to buyer, the supplier may select:

Payment not received

or

Others

depending on the nature of the issue.

Step 9: Add taxable value, rate and tax amount details

Enter the taxable value and GST rate. The tax amount is system-calculated based on the rate and taxable value. Multiple rate rows can be added for one invoice where required.

Step 10: Add remarks

The remarks should be short, clear and factual. The portal provides a remarks limit of 200 characters.

Example remark:

Payment against Invoice No. 45 dated 10/04/2026 is pending. Kindly verify and arrange payment or confirm if already paid.

Step 11: Upload attachment, if required

Supporting documents may be uploaded. The portal allows up to four files in JPEG or PDF format with maximum file size of 5 MB each.

Examples of attachments:

Invoice copy

Ledger copy

Payment reminder letter

Statement of outstanding balance

Step 12: Send notification

After verifying the details, click Send. Once the notification is sent, the counterparty receives intimation. The GST portal manual states that on successful receipt of a new notification or reply, SMS and email will be sent to the receiver, and an alert will also appear on the GST portal.

Step 13: Check Outbox

After sending, the supplier can check the Outbox and select the To Recipient tab to view notifications sent to buyers.

How buyer can view and reply

The buyer can login to the GST portal and go to:

Services > User Services > Communication Between Taxpayers > Inbox

The buyer can view the notification, download attachments, check document details, and reply or take action. The portal allows reply through the Inbox using the “Reply/Take Action” option. However, for one notification, reply can be sent only once.

Use cases for suppliers

A supplier may use communication to buyer in the following situations:

1. Payment not received

Where payment remains outstanding, especially where 180 days from invoice date is approaching or has crossed.

2. Buyer disputes invoice

Where the buyer says invoice does not belong to him or requires amendment.

3. Credit note or debit note issue

Where buyer and supplier need to align GST reporting.

4. Outstanding GST-inclusive amount

Where buyer has paid basic amount but GST component is pending.

5. Documentation trail

Where the supplier wants to maintain a GST portal record of communication.

Use cases for buyers

The same facility is also useful for buyers. A buyer can send communication to supplier where:

-Invoice is not appearing in GSTR-2B.

-Supplier has not filed GSTR-1.

-Wrong GSTIN has been mentioned.

-Wrong invoice value or tax amount has been uploaded.

-Credit note or debit note is missing.

-Supplier has uploaded an invoice wrongly to the buyer’s GSTIN.

-Payment has already been made and supplier needs to update records.

The portal allows recipients to ask suppliers to file missing documents, amend rejected documents, confirm wrongly uploaded documents, re-upload documents, or confirm that payment has been made.

Important practical precautions

This feature should be used carefully. A wrong or casual communication may create an unwanted record on the GST portal. Before sending any communication, taxpayers should verify:

-Correct GSTIN of buyer or supplier

-Correct invoice number and date

-Correct taxable value and tax amount

-Correct return period

-Ledger balance

-Actual payment status

-Whether any credit note, debit note or adjustment exists

-Whether the matter is already resolved outside the portal

Once a notification is sent, it cannot be modified. The GST portal manual specifically states that modifications can be made before sending, but no such modifications can be done once the notification has been sent to the counterparty.

What this feature does not do

-Taxpayers should not misunderstand the legal effect of this tab. Communication to buyer:

-Does not automatically recover payment.

-Does not automatically reverse the buyer’s ITC.

-Does not cancel or amend an invoice by itself.

-Does not replace GSTR-1 amendment.

-Does not replace credit note or debit note issuance.

-Does not replace legal notice or contractual remedies.

-Does not automatically prove default in all cases.

-Does not reduce supplier’s output GST liability merely because buyer has not paid.

It is a communication and documentation facility. The actual GST treatment must still be done through proper returns, books of accounts, reconciliations and legal documentation.

Suggested format for supplier’s remark to buyer

-Where payment is pending, the supplier may write:

Payment against Invoice No. XXXXX dated XXXX for taxable value Rs.XXXX and GST Rs.XXXX  is pending in our books. Kindly verify and arrange payment or confirm if already paid.

-Where 180 days have crossed, the supplier may write:

Payment against Invoice No. XXXXX  dated XXXXX  is pending beyond 180 days. Kindly verify records and take necessary action as per GST provisions, if applicable.

Where buyer says invoice does not belong to him, the supplier may write:

Invoice uploaded against your GSTIN as per our records. Kindly verify purchase order, delivery record and accounting entry and confirm discrepancy, if any.

Conclusion

The “Communication to Buyer” facility on the GST portal is a practical compliance tool for suppliers and recipients. It helps create a formal GST portal-based communication trail for invoice-related issues, missing documents, payment status, amendments and other document-level matters.

For suppliers, it can be especially useful where payment has not been received from the buyer. For buyers, it is useful where invoices are missing from GSTR-2B or documents require correction by the supplier.

However, taxpayers should use it with accuracy and caution. It is not a substitute for proper accounting, return filing, GST reconciliation, legal documentation or recovery action. When used properly, it can become an important part of GST compliance discipline and evidence management.

Disclaimer: This article is for informational purposes only and should not be construed as legal or professional advice. Taxpayers should consult their tax advisor based on the facts of their specific case before taking any action.