Reverse Charge Mechanism (RCM) Under GST: A Practical Guide

In the normal GST flow, the supplier charges GST on the invoice and pays it to the government. Under the Reverse Charge Mechanism (RCM), that flow flips: the recipient pays the GST directly, and the supplier's invoice doesn't include it. RCM applies to specific notified categories of supply, and the rules trip up businesses that haven't run into it before. Here is the working understanding.

What RCM is, in one sentence

Reverse Charge Mechanism shifts the GST liability from the supplier to the recipient for certain notified categories of supply.

The recipient:

• Pays the GST as if they were the supplier (charging themselves)
• Reports it as their own output GST
• Claims it as input tax credit (ITC) — subject to normal ITC rules
• The net cash impact is zero (you pay it and reclaim it) — provided you're eligible for ITC

The cash neutrality is the key. RCM is mostly a compliance burden, not a cost burden — except when ITC isn't fully available.

Why RCM exists

Two main reasons:

• Hard-to-tax suppliers — sectors where collection from suppliers is impractical (small unregistered providers, individual professionals, importers of services from abroad)
• Specific policy choices — certain categories where the government prefers the recipient to pay (often the more organised party in the transaction)

By shifting the obligation, GST collection happens reliably even when the supplier isn't well-positioned to handle it.

Notified categories under RCM (Section 9(3))

A non-exhaustive list of the more common categories:

• Goods Transport Agency (GTA) services — most freight bills where the GTA hasn't opted for forward charge
• Legal services by an individual advocate or firm to a business entity
• Services by an arbitral tribunal
• Sponsorship services
• Services by directors of a company to the company (sitting fees etc.)
• Insurance agent commissions
• Recovery agent services
• Import of services (services received from outside India)
• Renting of motor vehicles for transport of passengers, in some cases
• Security services provided to a registered person (post-2019 notification)

The list is amended from time to time. Always confirm against the latest CBIC notification for your specific transaction.

Section 9(4) — supplies from unregistered persons

Originally, RCM was much broader: any registered person receiving goods or services from an unregistered person had to pay RCM. This was suspended in 2017 due to practical issues and is now applied selectively — to specific categories notified by the government.

The current position (as of 2026): RCM under Section 9(4) is limited to specific notified categories (such as supplies of certain goods to e-commerce operators, supplies in the real estate sector, etc.). For most businesses, broad RCM on unregistered purchases does not apply — but check before assuming.

The self-invoice requirement

For RCM transactions where the supplier hasn't issued (or can't issue) a tax invoice — typically unregistered suppliers — the recipient must issue a self-invoice under Rule 46 within 30 days of receipt. The self-invoice contains the same details a normal tax invoice would.

This is a real compliance step. Skipping it doesn't make the GST disappear; it just adds an audit risk later.

How to record RCM in your books

For an RCM transaction, say a legal service worth ₹50,000 at 18%:

• The supplier's invoice is for ₹50,000 (no GST)
• You pay them ₹50,000
• In your books, you book GST under RCM separately:
  • Debit: Legal fees ₹50,000
  • Debit: Bank ₹50,000 (the payment)
  • Debit: GST Input ITC (under RCM) ₹9,000
  • Credit: GST Output (under RCM) ₹9,000
• The ₹9,000 GST appears as both your output liability AND your input credit
• Net: cash neutral if you're eligible for full ITC

In GSTR-3B:

• Table 3.1(d) — outward supplies on which RCM is payable (the ₹9,000 output)
• Table 4(A)(3) — ITC available on inward supplies liable to RCM (the ₹9,000 input)

When RCM is not cash-neutral

RCM is cash-neutral only when you can claim full ITC. It becomes a real cost when:

• You're an exempt supplier (your output is GST-exempt) — no ITC available
• The expense is a blocked credit (Section 17(5)) — RCM still applies but ITC doesn't
• You're using the Composition Scheme — pay RCM but no ITC

For these cases, RCM is a genuine additional cost, not just a paperwork exercise. Factor it into pricing.

The timing question

RCM liability arises at the earlier of:

• Date of payment, or
• 60 days from the date of the supplier's invoice (or 30 days, depending on category)
• Date of receipt of service (for services)

In practice, most businesses recognise RCM at the date of payment, which is simplest and works for most cases. But know the rule, because for services received in March and paid in May, RCM may need to be recognised in March's return — not May's — if the 30/60-day rule kicks in.

The most common RCM mistake

The most common mistake we see is forgetting to apply RCM on freight invoices. A small business pays a transporter, doesn't issue a self-invoice, doesn't book RCM, doesn't claim ITC. Years later, an audit picks it up — the GST is owed (often with interest), and the ITC for those years is time-barred.

The discipline: every GTA / freight bill triggers an RCM workflow at booking time. Don't let it slip.

How Booksmor helps

Booksmor identifies expense categories that typically trigger RCM, prompts for the self-invoice where needed, posts the GST entries on both the output and input sides, and surfaces RCM liability in GSTR-3B in the right tables. Audit reports show every RCM transaction with its ITC claim and self-invoice reference. Start a 30-day free trial and stop missing RCM in your books.