GST E-Invoicing for Reverse Charge and Import of Services from 1 January 2027: What Your Billing Software Must Change

Updated 2 November 2026. This is a technology guide, not tax advice. Confirm how the rules apply to your business with your CA.

Short answer: from 1 January 2027, GST e-invoicing will also apply to purchases you make from unregistered suppliers under reverse charge (RCM) and to services you import from outside India. Until now e-invoicing was mainly about the invoices you issue to registered buyers and for exports. This change pulls part of your purchase side into the Invoice Registration Portal (IRP), so your billing or ERP software needs to be ready before the new year.

What has changed

• The 57th GST Council meeting on 8 October 2026 recommended extending e-invoicing to RCM inward supplies from unregistered persons and to import of services, for taxpayers already under e-invoicing (aggregate annual turnover of Rs 5 crore or more), as reported by VATupdate.
• CBIC then issued Notification No. 04/2026-Central Tax dated 26 October 2026, amending the 2020 e-invoicing notification so that the covered transactions include supplies received from unregistered persons under reverse charge and import of services, effective 1 January 2027, according to StudyCafe and Taxscan.
• GSTN has already put two new supply types, RCMDOM (domestic RCM from unregistered persons) and RCMIMP (import of services), into the IRP sandbox under Advisory No. 678, with the registered recipient generating the IRN on its self-invoice, as summarised by CalcGuru.

Earlier press reports had pointed to April 2027, so you may still see that date online. Go by the notification and any later GSTN advisory.

Who is affected

If your business is already generating e-invoices (turnover of Rs 5 crore or more in any year since 2017-18), assume you are in scope. Typical cases:

• A manufacturer or trader that buys specified goods or services from unregistered suppliers where tax is paid under reverse charge.
• A company that pays for foreign SaaS tools, cloud hosting, advertising platforms or consultants outside India (import of services).
• Groups with several GSTINs where each unit raises its own self-invoices.

Smaller businesses below the threshold are not pulled in by this change, but their software vendors will be updating anyway, so it is a good time to check that your own billing data is clean.

What it means in practice

Today, for RCM and imported services, you usually raise a self-invoice inside your books and report it in your returns. From 1 January 2027 that self-invoice will also need to be registered on the IRP, get an IRN and a signed QR code, just like a sales e-invoice. In other words, a document that used to live only in your accounting system now has to pass the IRP's validations.

Billing and ERP software checklist

1. New document flow for self-invoices. Your software needs a clear way to create an RCM or import-of-services self-invoice, separate from normal purchase entries, with its own numbering series.
2. Support for RCMDOM and RCMIMP. The JSON sent to the IRP must carry the correct supply type. Check that your e-invoice module or GSP integration has added these types and that you can test them in the sandbox.
3. Supplier master for unregistered and foreign vendors. Name, address, state or country, and the details the schema asks for. Foreign vendors need clean country codes; unregistered domestic vendors need correct state codes for place of supply.
4. Place of supply and tax type logic. Import of services is generally treated as inter-state, so IGST logic must be right. Wrong place of supply is the most common reason an IRP rejects a document.
5. Foreign currency handling. Invoices from overseas vendors are often in USD or EUR. Your system should store the original currency and the INR value used for tax, with the exchange rate.
6. Timing. Decide when the self-invoice is generated (for example, when the foreign invoice is booked or when payment is made) and make sure your team follows one rule. Ask your CA which point applies to you.
7. Error handling and retries. The IRP can be slow or down (it had a planned outage on 31 October - 1 November 2026). Queue documents, retry automatically and alert someone when a document is stuck.
8. Store the IRN and QR code. Save the acknowledgement number, date, IRN and signed QR with the self-invoice and show them on the printed or PDF copy.
9. Returns reconciliation. Check that the registered self-invoices match what flows into your GST returns, so tax paid under RCM and the input credit you claim line up.
10. Audit trail and access control. Record who created, edited or cancelled each self-invoice. Cancellation windows on the IRP are short, so limit who can cancel.

A simple plan for the next eight weeks

1. Week 1-2: list every RCM and import-of-services transaction from the last six months. Note the vendor, amount, currency and how it was booked.
2. Week 2-4: ask your software vendor or developer for their RCMDOM/RCMIMP roadmap, or plan the change if you run custom software. Clean up the vendor master.
3. Week 4-6: test in the IRP sandbox with real-looking data, including foreign currency and rejected cases.
4. Week 6-8: train the accounts team, write a one-page process note and do a dry run for December transactions.

Ready-made software or custom?

If you use a popular accounting package, the update will probably arrive as a version upgrade; your job is to install it, fix master data and test. If you run custom billing or ERP software, someone has to build the new flow. That is usually a contained piece of work (new document type, JSON mapping, API calls, storage of IRN and QR, reports) if the original system was designed with a proper e-invoice module. Read our comparison of Tally vs custom billing software and our GST billing software checklist for a wider view.

Frequently asked questions

Does this apply to my small shop?

Only if you are already required to issue e-invoices, which today means aggregate annual turnover of Rs 5 crore or more. Check with your CA.

Who generates the IRN for an imported service?

The recipient in India, on its own self-invoice. The foreign supplier is not registered on the IRP.

Is the date final?

The CBIC notification, as reported, says 1 January 2027. Watch for GSTN advisories on the production go-live of the new supply types, which can add operational details.

What happens if my software is not ready?

Treat it as a compliance risk: a self-invoice without a valid IRN when one is required may not be accepted as proper documentation. Plan the update now rather than in late December.

Need help updating your billing software?

Nextinera builds and maintains GST billing and ERP systems, including e-invoice and e-way bill integrations. See our ERP software development and API integration services, or book a free call to review your current setup. We are a software company, not tax advisers.