GST Tip of the Day: Raise a Self-Invoice for Your Reverse-Charge Purchases

Most small-business owners think of an invoice as something the seller issues. Under the reverse charge mechanism (RCM), that assumption can quietly create a compliance gap. When you are the one liable to pay GST on a purchase, the law also expects you to document that purchase properly, often with a self-invoice.

Here is a practical tip you can act on today: review your RCM purchases and make sure each one has a corresponding self-invoice.

What is reverse charge, briefly

Normally the supplier collects GST from you and pays it to the government. Under RCM, that responsibility flips. The recipient (you) pays GST directly to the government instead of the supplier collecting it. Common RCM situations for small businesses include:

• Specified goods and services notified under Section 9(3) of the CGST Act (for example, legal services from an advocate, goods transport agency services, sponsorship services, and others as notified).
• Purchases from unregistered suppliers in certain notified cases under Section 9(4).

The exact list is governed by notifications and changes over time, so confirm whether a particular expense falls under RCM before applying it.

Why a self-invoice matters

When you buy from an unregistered supplier under RCM, that supplier cannot issue a GST tax invoice, because they are not registered. The GST law therefore requires the registered recipient to issue an invoice in respect of such inward supplies. This is the self-invoice.

Without it, you have a gap: you are paying tax on a supply with no proper tax document on record. That weakens your position during scrutiny and can complicate the input tax credit (ITC) you are otherwise entitled to claim on the RCM tax you paid.

The two-step nature of RCM

It helps to think of RCM as two separate actions:

1. Pay the tax. You discharge the GST liability in cash through your electronic cash ledger. RCM liability generally cannot be paid using ITC.
2. Claim the credit. Once paid, the same tax is usually available as ITC, provided the purchase is for business use and is not a blocked credit under Section 17(5).

So for eligible purchases, RCM is often tax-neutral over time, but only if you document and report it correctly.

A simple checklist for today

• List your recurring RCM expenses. Think advocate fees, goods transport agency freight, and any notified services or supplies from unregistered persons.
• Issue a self-invoice for purchases from unregistered suppliers that attract RCM. Include your GSTIN, the supplier details, description, value, applicable rate, and the tax amount.
• Maintain a payment voucher where required, as the law also contemplates a payment voucher at the time of paying the supplier.
• Report it in GSTR-3B. RCM liability is declared and paid in the relevant table of GSTR-3B, and eligible ITC is claimed in the appropriate ITC table.
• Pay in cash, then claim ITC in the same or a subsequent period as permitted.

Common mistakes to avoid

• Ignoring RCM because the vendor did not charge tax. The absence of tax on the bill does not remove your liability; in many RCM cases that is exactly the point.
• Trying to pay RCM using ITC. It is paid in cash through the cash ledger.
• Claiming RCM ITC without actually paying the tax. Credit follows payment.
• Skipping the self-invoice for unregistered purchases. This is a documentation requirement, not an optional formality.

The takeaway

Reverse charge is one of those areas where the tax may be neutral but the paperwork is not. Spend a few minutes today identifying your RCM purchases, raise self-invoices where required, and make sure the liability is paid in cash and reported in GSTR-3B. Getting the document trail right now saves you a far more painful reconstruction later, especially if a notice arrives. When in doubt about whether a specific expense attracts RCM, check the current notification or confirm with your tax advisor before applying it.