Introduction

Input Tax Credit, commonly known as ITC, is the backbone of GST. Under normal GST rules, a registered taxpayer can claim ITC on eligible purchases used for business. However, certain situations require special treatment.

Section 18 of the CGST Act deals with availability of credit in special circumstances. It explains when a taxpayer can claim ITC on stock, semi-finished goods, finished goods and capital goods during a transition, and when ITC must be reversed.

These situations usually arise when a taxpayer moves from one tax position to another, such as:

  • unregistered to registered;
  • composition scheme to regular scheme;
  • exempt supply to taxable supply;
  • regular scheme to composition scheme;
  • taxable supply to exempt supply;
  • cancellation of registration;
  • sale, merger, demerger or transfer of business; or
  • sale of capital goods on which ITC was already taken.

For GST return filing, ITC reconciliation and GST notice support, businesses may visit TaxClear.in.

What Is the Purpose of Section 18?

Section 18 is based on a simple principle. If a taxpayer was earlier not eligible to take ITC but later becomes liable to pay GST on outward supplies, the law allows ITC on eligible stock and, in some cases, capital goods.

Similarly, if a taxpayer had earlier claimed ITC but later moves to a position where outward supplies are not taxable in the normal manner, the law requires reversal of ITC.

In simple words:

SituationGST Treatment
Earlier no ITC, now taxable outputITC may become available
Earlier ITC taken, now no normal tax outputITC may have to be reversed
Business transferredUnutilised ITC may be transferred
Capital goods soldHigher of prescribed ITC amount or tax on transaction value is payable

Section 18(1): ITC Available in Special Circumstances

Section 18(1) covers cases where ITC becomes available because the taxpayer moves into a taxable GST position.

The law broadly allows ITC on:

  • inputs held in stock;
  • inputs contained in semi-finished goods;
  • inputs contained in finished goods; and
  • capital goods in specified cases.

However, the date on which stock is checked is very important.

1. Registration After Becoming Liable to Register

This applies where a person becomes liable for GST registration and applies for registration within 30 days from the date on which he becomes liable.

For example, a business was earlier unregistered. It crossed the turnover threshold and became liable to register. It applied for registration within 30 days and obtained GST registration.

In such a case, ITC is available on inputs held in stock, semi-finished goods and finished goods on the day immediately preceding the date from which the person becomes liable to pay tax.

Example

A trader becomes liable for GST registration on 25 August 2026 and applies within 30 days. He should check stock as on 24 August 2026. ITC may be claimed on eligible inputs contained in that stock.

ParticularsTreatment
Status before threshold crossingUnregistered
Status after crossing thresholdLiable for registration
Application time limitWithin 30 days
Stock date for ITCDay immediately preceding liability date
ITC available onInputs in stock, semi-finished goods and finished goods
ITC on capital goodsNot covered in this clause

2. Voluntary GST Registration

A person may voluntarily obtain GST registration even if turnover has not crossed the threshold. In this case, ITC becomes available from the date of grant of registration.

The taxpayer can claim ITC on inputs held in stock, semi-finished goods and finished goods on the day immediately preceding the date of grant of registration.

Example

A person voluntarily applies for GST registration and registration is granted on 10 September 2026. ITC may be claimed on eligible inputs held in stock on 9 September 2026.

ParticularsTreatment
Registration typeVoluntary
Relevant dateDate of grant of registration
Stock date for ITCDay immediately preceding grant date
ITC available onInputs in stock, semi-finished goods and finished goods
ITC on input servicesNot available
ITC on capital goodsNot covered in this clause

3. Composition Scheme to Regular Scheme

A composition taxpayer cannot normally collect GST from customers in the regular manner and cannot claim ITC. However, when the person exits the composition scheme and becomes liable to pay tax under the regular scheme, ITC becomes available.

This may happen when:

  • turnover exceeds the composition limit;
  • the taxpayer opts out of composition; or
  • the taxpayer becomes ineligible for composition.

In such cases, ITC is available on:

  • inputs held in stock;
  • inputs contained in semi-finished goods;
  • inputs contained in finished goods; and
  • capital goods, after prescribed reduction.

The relevant date is the day immediately preceding the date from which the person becomes liable to pay tax under the regular scheme.

ParticularsTreatment
Earlier statusComposition taxpayer
New statusRegular taxpayer
Stock date for ITCDay immediately preceding regular tax liability
ITC available on inputsYes
ITC available on capital goodsYes, after reduction
Form requirementForm GST ITC-01

4. Exempt Supply Becomes Taxable

If a registered person was making exempt supplies and those supplies later become taxable, ITC becomes available.

This situation may arise when the Government withdraws an exemption notification or changes taxability of a product or service.

In this case, ITC may be claimed on:

  • inputs held in stock;
  • inputs contained in semi-finished goods;
  • inputs contained in finished goods; and
  • capital goods exclusively used for such exempt supply, after prescribed reduction.

The relevant date is the day immediately preceding the date from which the exempt supply becomes taxable.

ParticularsTreatment
Earlier supplyExempt
New supplyTaxable
Stock dateDay before supply becomes taxable
ITC on inputsAvailable
ITC on capital goodsAvailable, after reduction
ITC conditionInputs/capital goods must relate to such supply

Capital Goods Credit Under Section 18(1)

For composition-to-regular and exempt-to-taxable situations, ITC on capital goods is also available. However, full ITC is not allowed if the capital goods were already used during the exempt or composition period.

The credit on capital goods must be reduced by the prescribed percentage.

Simple Illustration

Suppose capital goods were purchased in January and the supply becomes taxable in October. The capital goods were used during the earlier exempt period. Therefore, ITC is reduced for the period already used before becoming taxable.

The practical rule is to reduce credit by 5% per quarter or part thereof from the invoice date.

Capital goods ITCExample
Original ITC₹100
Period used before eligibility3 quarters
Reduction @ 5% per quarter₹15
Eligible ITC₹85

Section 18(2): One-Year Time Limit

Section 18(2) restricts ITC under Section 18(1). A taxpayer cannot take ITC in respect of any supply after the expiry of one year from the date of the tax invoice.

This means old stock may not always be eligible.

Example

If a taxpayer becomes eligible to claim ITC on 25 August 2026, invoice dates must be checked. ITC cannot be claimed if the invoice is older than one year from the relevant date.

ItemTreatment
Invoice within one yearITC may be available
Invoice older than one yearITC not available
Applies toITC claimed under Section 18(1)

Form GST ITC-01

To claim ITC under Section 18(1), the taxpayer must file Form GST ITC-01 within the prescribed time.

The practical compliance requirement is:

  • file ITC-01 within 30 days from becoming eligible to claim ITC;
  • disclose details of stock, semi-finished goods, finished goods and capital goods, as applicable;
  • if ITC claim exceeds ₹2 lakh, obtain certification from a Chartered Accountant or Cost Accountant.
Compliance PointRequirement
FormGST ITC-01
Time limitWithin 30 days of eligibility
Stock detailsRequired
Capital goods detailsRequired where applicable
CA/CMA certificateRequired if ITC exceeds ₹2 lakh

For GST ITC-01 filing, ITC computation and GST compliance support, businesses may use TaxClear’s GST services.

Section 18(3): Transfer of ITC on Business Reorganisation

Section 18(3) deals with transfer of unutilised ITC when there is a change in the constitution of a registered person.

This may happen due to:

  • sale of business;
  • merger;
  • demerger;
  • amalgamation;
  • lease; or
  • transfer of business.

The key condition is that there must be specific provision for transfer of liabilities.

Example

A Ltd. and B Ltd. merge into AB Ltd. Both companies have unutilised ITC in their electronic credit ledgers. If the merger arrangement includes transfer of liabilities, unutilised ITC can be transferred to the new entity in the prescribed manner.

SituationITC Treatment
Sale of business with liabilitiesITC may be transferred
Merger with liabilitiesITC may be transferred
Amalgamation with liabilitiesITC may be transferred
DemergerITC apportioned based on value of assets
Transfer without liability clauseITC transfer may be disputed

ITC Transfer in Demerger

In case of demerger, ITC is apportioned in the ratio of the value of assets of the new units as specified in the demerger scheme.

Example

AB Ltd. is demerged into A Ltd. and B Ltd. AB Ltd. has unutilised ITC. The ITC will be distributed between A Ltd. and B Ltd. based on the value of assets transferred to each entity as per the demerger scheme.

Section 18(4): ITC Reversal When Regular Taxpayer Moves to Composition or Exempt Supply

Section 18(4) is the reverse of Section 18(1).

If a registered taxpayer who has taken ITC:

  • opts to pay tax under the composition scheme; or
  • his goods or services become wholly exempt,

then the taxpayer must reverse ITC.

Reversal applies to:

  • inputs held in stock;
  • inputs contained in semi-finished goods;
  • inputs contained in finished goods; and
  • capital goods, after prescribed reduction.

The relevant date is the day immediately preceding the date of switch-over or the date of exemption.

SituationITC Treatment
Regular scheme to composition schemeITC reversal required
Taxable supply becomes exemptITC reversal required
Inputs in stockReverse proportionate ITC
Semi-finished/finished goodsReverse embedded input ITC
Capital goodsReverse based on remaining useful life

ITC Reversal: Credit Ledger vs Cash Ledger

A common practical issue arises when the electronic credit ledger has insufficient balance.

The reversal is not based only on the balance available in the electronic credit ledger. It is based on eligible stock and capital goods held on the relevant date.

If the credit ledger balance is not enough, the balance amount must be paid through the electronic cash ledger.

Example

A taxpayer claimed ₹100 ITC on stock and used the credit for paying earlier GST liability. Later, the taxpayer shifts from regular scheme to composition scheme while the same stock remains unsold.

Even if the electronic credit ledger balance is nil, ITC reversal of ₹100 may still be required. The taxpayer may have to pay through the cash ledger.

How to Calculate ITC Reversal on Inputs

For inputs held in stock, semi-finished goods and finished goods, ITC reversal is generally calculated on the basis of corresponding tax invoices.

If invoices are not available, the taxpayer may use the prevailing market price, supported by reasonable valuation and documents.

SituationReversal Basis
Invoice availableBased on invoice ITC
Invoice not availableBased on prevailing market price
Stock used partlyProportionate calculation
Credit ledger insufficientPay balance through cash ledger

ITC Reversal on Capital Goods Under Section 18(4)

For capital goods, useful life is generally taken as five years, i.e. 60 months.

The amount attributable to the remaining useful life must be reversed.

Example

Capital goods had original ITC of ₹100. The taxpayer used them for 4 years and 7 months. Therefore, only 5 months of useful life remain out of 60 months.

Reversal amount:

₹100 × 5 / 60 = ₹8.33

ParticularsAmount
Original ITC₹100
Total useful life60 months
Remaining useful life5 months
ITC reversal₹8.33

Section 18(6): Sale of Capital Goods or Plant and Machinery

Section 18(6) applies when a registered person supplies capital goods or plant and machinery on which ITC has been taken.

In such a case, the taxpayer must pay the higher of:

  • ITC taken on such capital goods reduced by prescribed percentage; or
  • tax on transaction value under Section 15.

Example

A machine was purchased and ITC of ₹100 was taken. It is sold after 3 quarters.

Reduced ITC:

₹100 – 15% = ₹85

Tax on transaction value:

₹70

Amount payable:

Higher of ₹85 and ₹70 = ₹85

ParticularsAmount
Original ITC₹100
Reduction @ 5% for 3 quarters₹15
Reduced ITC₹85
Tax on transaction value₹70
GST payable₹85

Scrap Sale of Certain Capital Goods

There is a special proviso for certain items supplied as scrap, such as:

  • refractory bricks;
  • moulds and dies;
  • jigs; and
  • fixtures.

Where these are supplied as scrap, the taxable person may pay tax on transaction value under Section 15.

Quick Summary of Section 18

SectionSituationITC Treatment
18(1)(a)Registration within 30 days after becoming liableITC on inputs in stock
18(1)(b)Voluntary registrationITC on inputs in stock
18(1)(c)Composition to regularITC on inputs and capital goods
18(1)(d)Exempt supply becomes taxableITC on inputs and capital goods
18(2)Invoice older than one yearITC not available
18(3)Business sale/merger/demerger/transferUnutilised ITC transfer allowed
18(4)Regular to composition/exemptITC reversal required
18(6)Sale of capital goods/plant machineryHigher of reduced ITC or transaction value tax

Practical Checklist for GST Taxpayers

Before claiming or reversing ITC under Section 18, check:

  • Whether the taxpayer is moving from unregistered to registered.
  • Whether registration application was filed within 30 days where required.
  • Whether registration is voluntary.
  • Whether the taxpayer is moving from composition to regular.
  • Whether exempt supply has become taxable.
  • Whether invoices are within one year.
  • Whether ITC-01 is required.
  • Whether CA/CMA certificate is required.
  • Whether capital goods credit must be reduced.
  • Whether business transfer includes transfer of liabilities.
  • Whether ITC reversal is required due to composition/exemption/cancellation.
  • Whether capital goods are being sold.
  • Whether transaction value tax or reduced ITC is higher.

For GST return filing, ITC-01, ITC reversal, GST audit support and notice handling, visit TaxClear.in.

Key Takeaways

  • Section 18 deals with ITC in special circumstances.
  • ITC may become available when a person moves into the GST taxable chain.
  • ITC may need to be reversed when a person moves out of normal taxable supply.
  • ITC on stock is checked on the day immediately preceding the relevant event.
  • ITC on capital goods is available only in specified cases and after reduction.
  • Invoices older than one year are not eligible for ITC under Section 18(1).
  • ITC-01 filing is important for claiming credit.
  • Business transfer ITC is allowed only where liabilities are also transferred.
  • Sale of capital goods requires comparison between reduced ITC and tax on transaction value.

Conclusion

Section 18 of the CGST Act is important because it deals with transition situations. A taxpayer may become eligible for ITC when moving from unregistered to registered, composition to regular, or exempt to taxable supplies. At the same time, ITC reversal may be required when moving from regular to composition or from taxable to exempt supplies.

The key to correct GST compliance is identifying the relevant event date, checking eligible stock, reviewing invoice dates, calculating capital goods credit correctly and filing the required form within time.

Businesses should not claim or reverse ITC casually in such cases. A proper working paper should be maintained for stock, invoices, capital goods, credit ledger and cash ledger adjustments.

For professional GST compliance, ITC computation, ITC-01 filing and GST notice support, visit TaxClear.in.

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