Taxation · Registration

Special Registrations under GST: Casual, Non-Resident, ISD, TDS/TCS

Updated 5 October 2026 · Fact-checked

Special registrations apply to persons who do not fit the normal regular-taxpayer pattern: casual taxable persons, non-resident taxable persons, input service distributors, tax deductors, tax collectors and OIDAR suppliers. For each, identify the category, then state the threshold, timing, validity, deposit and conditions. Compare the categories to avoid mixing them up.

Understand Special Registrations: Casual, Non-Resident, ISD, TDS/TCS

Most suppliers register under GST in the normal way, with a fixed place of business in the State and a turnover threshold. Some persons cannot be handled that way. They supply occasionally, they live abroad, they only distribute credit, or they only deduct or collect tax. The law therefore gives them special registration rules.

A casual taxable person (CTP) occasionally supplies goods or services in a State or Union territory where he has no fixed place of business or residence. A non-resident taxable person (NRTP) occasionally supplies goods or services but has no fixed place of business or residence in India. The key difference is the location: a CTP is in India but works in a State or Union territory where he has no fixed place of business or residence, while an NRTP is based outside India.

Both must apply for registration at least 5 days before they commence business. There is no turnover threshold for them. They must also make an advance deposit of estimated tax liability for the period of registration, and this deposit is made at the time of submitting the application (section 27). A CTP or NRTP cannot opt for composition. The registration is temporary: it lasts for the period stated in the application, or 90 days, whichever is earlier, and can be extended.

An input service distributor (ISD) is an office of the supplier that receives tax invoices for input services and distributes the credit to its branches with the same PAN. A person who wishes to act as an ISD needs a separate registration for the ISD office, under the same PAN as the units it serves. From 1 April 2025 (as amended by the Finance Act, 2024), the ISD mechanism is mandatory for distributing input tax credit on common input services, and the ISD issues its distribution invoices only to recipient units having the same PAN. The ISD office is registered for distributing credit. If the entity makes its own outward supplies, it holds a regular registration for them.

A tax deductor (specified persons under section 51 of the CGST Act, such as government departments, local authorities, governmental agencies and other notified persons) and a tax collector (an e-commerce operator liable to collect tax under section 52 of the CGST Act) must register regardless of turnover. Section 24(vi) makes registration compulsory for persons required to deduct tax under section 51, and section 24(x) makes it compulsory for an e-commerce operator required to collect tax under section 52. Only an e-commerce operator who is liable to collect tax under section 52 falls in the collector category. This registration is separate from any registration they may need for their own supplies.

A person supplying OIDAR (online information and database access or retrieval) services from outside India to a non-taxable online recipient in India must also register under a simplified procedure, with no threshold. Under section 2(16) of the IGST Act, a non-taxable online recipient is a government, a local authority, a governmental authority, an individual or any other person in India who is not registered and who receives OIDAR services for a purpose other than commerce, industry or any other business or profession. A non-resident OIDAR supplier registers under the simplified procedure (OIDAR registration) and pays the tax. A representative may be appointed in India for the purpose of paying the tax on his behalf.

Key rules to remember

Casual taxable person: when to register: Apply at least 5 days before commencing business; the advance deposit of estimated tax is made at the time of application; No turnover threshold applies. The application is made at least 5 days before the business starts in the State, and the advance deposit of estimated tax is made when the application is submitted (section 27).
CTP/NRTP validity: Validity = period stated in application or 90 days, whichever is earlier; Can be extended by a further period not exceeding 90 days, on application before expiry, after a further deposit.
Advance deposit: Deposit = estimated tax liability for the whole period of registration; It is paid into the electronic cash ledger at the time of submitting the application. For an extension, a further deposit of estimated liability for the extended period is needed.
Returns for CTP/NRTP: CTP: GSTR-1 and GSTR-3B (as for regular taxpayers). NRTP: GSTR-5; A CTP files GSTR-1 and GSTR-3B like a regular taxpayer. An NRTP files GSTR-5 by the 20th of the following month or within 7 days after the registration expires, whichever is earlier.
NRTP application: Apply at least 5 days before commencing business; the advance deposit of estimated tax is made at the time of application; The NRTP applies with its PAN, or with a passport or other prescribed document if it is a foreign national with no PAN. An Indian mobile number and email are needed for OTP verification.
ISD registration: A person acting as ISD needs a separate ISD registration for the ISD office, under the same PAN; The ISD distributes credit only to recipients having the same PAN. From 1 April 2025 (as amended by the Finance Act, 2024), the ISD mechanism is mandatory for distributing input tax credit on common input services. The entity holds a regular registration for its own outward supplies.
Tax deductor and collector: Registration required without regard to turnover threshold: section 24(vi) for deductors, section 24(x) for e-commerce operators liable to collect tax; Under TDS (section 51), specified persons such as government departments, local authorities and governmental agencies deduct, along with other notified persons. Only e-commerce operators liable to collect tax under section 52 register as tax collectors. The registration is for deducting or collecting tax and is separate from any registration for own supplies.
OIDAR supplier from outside India: Registration is mandatory if supplying OIDAR services to non-taxable online recipients in India; no threshold; A non-taxable online recipient (section 2(16) of the IGST Act) is a government, local authority, governmental authority, individual or other person in India who is not registered and who receives OIDAR services for a purpose other than commerce, industry or any other business or profession. A simplified registration procedure applies. A non-resident OIDAR supplier registers under the simplified procedure (OIDAR registration) and pays the tax. A representative may be appointed in India for the purpose of paying the tax on his behalf.

How to solve Special Registrations: Casual, Non-Resident, ISD, TDS/TCS questions

Use this method for any question on special registration. The marks come from naming the right category and stating the correct rule.

1Read the facts and find the key words: occasional supply, fixed place of business or residence, residence in India, distributing credit, deducting or collecting tax.
2Classify the person: CTP, NRTP, ISD, tax deductor, tax collector or OIDAR supplier.
3Check whether a turnover threshold applies. For these categories, it generally does not.
4State the timing: registration before starting supplies, at least 5 days in advance for CTP and NRTP.
5State the validity period and the advance deposit of estimated tax, including any extension rules.
6Apply any restrictions, such as no composition option for CTP and NRTP.
7Write the conclusion in one clear sentence, linking the facts to the rule.

Quickest way: Category-first elimination

When to use it: Use it in MCQs and the first lines of a written answer when time is short.

Underline the status: a person in India with no fixed place of business or residence in the State means CTP; no fixed place of business or residence in India means NRTP.
Eliminate options that quote a turnover threshold for CTP, NRTP, ISD, deductor or collector.
Memorise the set: apply at least 5 days before commencing business, 90 days validity, extension up to 90 days, and advance deposit of estimated tax made at the time of application.
For written answers use this format: provision, facts, conclusion. Write each in one or two lines for step marks.
If the question says credit is being distributed to branches, answer ISD and check same PAN.

Common mistakes in Special Registrations: Casual, Non-Resident, ISD, TDS/TCS

Applying the normal turnover threshold to a CTP or NRTP.
Students remember the general rule for regular suppliers and apply it everywhere.
Fix: Remember that these categories must register regardless of turnover, before they start the supply.
Confusing CTP with NRTP.
Both are occasional suppliers with temporary registration.
Fix: Ask where the person is based. Outside India means NRTP. A person in India with no fixed place of business or residence in that State means CTP.
Forgetting the advance deposit.
Students focus on the registration timing and validity only.
Fix: Always state that the estimated tax liability for the registration period is deposited in advance.
Saying a CTP can opt for composition.
Students link low turnover with composition.
Fix: State that CTP and NRTP are not eligible for composition.
Assuming an existing regular registration covers ISD activity.
Students think one registration per PAN per State is enough.
Fix: State that a separate ISD registration is required for distributing credit.
Distributing ISD credit to units with a different PAN.
Students treat all group entities as branches.
Fix: Check that the PAN of each recipient is the same as the ISD PAN.

Worked examples

Example 1

Rohan, a registered dealer in Maharashtra, plans to set up a stall at a trade fair in Gujarat for 10 days where he has no fixed place of business or residence. He expects to supply goods with an estimated tax liability of ₹80,000. Advise him on registration.

Show the solution

Rohan will occasionally supply goods in Gujarat, where he has no fixed place of business or residence, so he is a casual taxable person there.
A CTP must register regardless of turnover. The application should be made at least 5 days before the business starts.
He must deposit the estimated tax liability of ₹80,000 for the period of registration in advance, at the time of submitting the application.
The registration will be valid for the period he states or 90 days, whichever is earlier. Here the fair lasts 10 days, so he applies for that period.
He cannot opt for composition as a CTP.

Answer: Rohan must apply for a casual taxable person registration in Gujarat at least 5 days before the fair and deposit ₹80,000 in advance, at the time of application. The registration will be valid for the stated period of 10 days, extendable if needed.

Example 2

Distinguish between a casual taxable person and a non-resident taxable person under GST.

Show the solution

Meaning: A CTP occasionally supplies in a State or Union territory where he has no fixed place of business or residence. An NRTP occasionally supplies but has no fixed place of business or residence in India.
Location: CTP is generally an Indian person; NRTP is based outside India.
Registration timing: both must apply at least 5 days before commencing business.
Threshold: neither has a turnover threshold.
Validity: both are valid for the stated period or 90 days, whichever is earlier, with extension up to 90 days.
Advance deposit: both deposit estimated tax liability in advance, at the time of submitting the application.
Returns: a CTP files GSTR-1 and GSTR-3B; an NRTP files GSTR-5.
Composition: both are ineligible.

Answer: The main difference is residence and place of business: a CTP is in India but has no fixed place of business or residence in the State of supply, while an NRTP has neither a fixed place of business nor residence in India. The timing, validity, deposit and composition rules are the same for both, but the returns differ.

Exam tips

Write the definition first, then apply it to the facts. Examiners award marks for the category and the conclusion.
In a comparison question, use a point-by-point list with the same headings for both persons.
Always mention the advance deposit and the 90-day validity for CTP and NRTP when asked about registration.
For ISD, state the separate registration and the same-PAN condition in one line.
If unsure of a section number, state the rule in words rather than guess.

Practice questions from Registration

Special Registrations: Casual, Non-Resident, ISD, TDS/TCS: frequently asked questions

What is the validity of a casual taxable person registration?

It is valid for the period stated in the application or 90 days from the effective date, whichever is earlier. It can be extended by a further period not exceeding 90 days before it expires. A further deposit is needed for the extended period.

Is there a turnover threshold for CTP and NRTP registration?

No. These persons must register before they start making taxable supplies, regardless of turnover. This is a compulsory registration category.

Does an ISD need a separate registration?

Yes. A person who wishes to act as an input service distributor needs a separate ISD registration for the ISD office, under the same PAN. Credit can be distributed only to recipients having the same PAN.

Who needs to register for TDS and TCS under GST?

Persons required to deduct tax under section 51, such as government departments, local authorities and governmental agencies and other notified persons, must register under section 24(vi). E-commerce operators liable to collect tax under section 52 must register as tax collectors under section 24(x). No turnover threshold applies to them for this purpose.