Direct and Indirect Taxation · Tax Invoice - Electronic Way Bill

Tax Invoice under GST: Meaning, Time and Contents

Updated 10 October 2026 · Fact-checked

A tax invoice is the document a registered supplier issues to record a taxable supply and the tax charged. For goods, issue it before or at removal or delivery. For services, issue it within 45 days of supply (30 days for insurers, banks and NBFCs). Include the prescribed particulars. Copies: three for goods, two for services.

Understand Tax Invoice: Meaning, Time and Contents

A tax invoice is the main document of a GST supply. It tells the recipient what was supplied, at what value and how much tax was charged. The recipient needs it to claim input tax credit. The supplier needs it as proof of the supply and of the tax collected.

The duty comes from section 31 of the CGST Act, 2017, and Rules 46 to 48 of the CGST Rules, 2017. A registered person making a taxable supply must issue a tax invoice. A person under the composition scheme does not issue a tax invoice. They issue a bill of supply, and they cannot charge tax.

The law asks three things. When must you issue it (time limits differ for goods and services). What must it contain (the prescribed particulars). How many copies (the original goes to the recipient, the duplicate to the transporter for goods, and the triplicate is kept by the supplier). Most exam questions test one of these three.

Remember the time of issue is a compliance date. It is separate from the time of supply, which fixes when tax becomes payable. Do not mix the two when you answer.

Key rules to remember

Time of issue: supply of goods (normal case): Issue invoice before or at the time of removal of goods (if movement is involved), or before or at the time of delivery or making goods available to the recipient (if no movement); Where goods are sent on approval, issue the invoice before or at the time of supply, or within 6 months from the date of removal, whichever is earlier.
Time of issue: supply of services: Within 45 days from the date of supply of service; For an insurer, banking company, financial institution or NBFC, the period is 30 days.
Continuous supply of goods: Invoice on or before the date of each statement of accounts or each payment; Applies where goods are supplied continuously and the statement or payment dates are fixed.
Continuous supply of services: Due date of payment fixed in the contract: invoice on or before that due date. Due date not ascertainable: on or before actual payment is received. Payment linked to completion of an event: on or before completion; Choose the case from the contract wording.
Number of copies: goods: Three copies: Original for Recipient, Duplicate for Transporter, Triplicate for Supplier; Rule 46 requires a serially numbered invoice in triplicate for goods.
Number of copies: services: Two copies: Original for Recipient, Duplicate for Supplier; Rule 46 requires it in duplicate for services.
Mandatory particulars (Rule 46): Name, address and GSTIN of supplier; consecutive serial number (max 16 characters, letters, numerals, hyphen or slash); date of issue; recipient name, address and GSTIN if registered; HSN code of goods or accounting code of services; description; quantity and unit for goods; total value; taxable value after discount; rate and amount of CGST, SGST/UTGST, IGST and cess; place of supply with state name if different from delivery state; address of delivery if different from place of supply; whether tax is payable on reverse charge; signature or digital signature of supplier or authorised person; Recipient details are needed in full when the recipient is registered. For an unregistered recipient, the rules set value-based conditions for including name and address.
Invoice number rule: Serial number must be unique for a financial year; It can contain a maximum of sixteen characters.

How to solve Tax Invoice: Meaning, Time and Contents questions

Use this order for any question on tax invoice. It keeps your answer complete and gets step marks.

1Check whether the supplier is a regular registered person. If the supplier is under composition or the supply is exempt, a bill of supply applies, not a tax invoice.
2Identify whether the supply is goods or services. This decides the time limit and the number of copies.
3For goods, check whether movement is involved, whether it is a continuous supply or goods sent on approval. Fix the last date of issue accordingly.
4For services, count 45 days from the date of supply (30 days for insurer, bank, financial institution or NBFC). Check the date carefully, and watch for a continuous supply.
5If the question asks for contents, list the prescribed particulars in a clean bullet list, starting with supplier details and invoice number and ending with signature.
6State the number of copies and who receives each one.
7Write the conclusion in one line, such as the last date of issue or the missing particulars.

Quickest way: Goods or services, then date, then copies

When to use it: Use for MCQs and short numerical date questions where you must give the last date of invoice or the number of copies.

Goods: remember 'removal or delivery' as the deadline. Services: remember 45 days (30 for banks, insurers, NBFCs).
Goods: three copies, with the duplicate going to the transporter. Services: two copies.
For an invoice-date question, add the days to the date of supply. Count the day after supply as day 1.
If the supplier is a composition dealer or the supply is exempt, choose bill of supply immediately.

Common mistakes in Tax Invoice: Meaning, Time and Contents

Writing 30 days as the time limit for all services.
Students confuse the general rule with the special rule for banks, insurers and NBFCs.
Fix: Use 45 days for normal service providers and 30 days only for insurers, banking companies, financial institutions and NBFCs.
Giving three copies for services.
The triplicate rule for goods is remembered and applied everywhere.
Fix: Learn the pair: goods in triplicate, services in duplicate. The transporter's copy exists only for goods.
Treating time of issue of invoice as time of supply.
Both topics use the invoice date, so they look alike.
Fix: Time of issue is a compliance deadline under section 31. Time of supply is a separate rule that fixes the tax liability date. Answer only what is asked.
Asking a composition dealer to issue a tax invoice with tax.
Students forget that a composition person cannot collect tax from the recipient.
Fix: A composition dealer issues a bill of supply. Mention it and note that tax cannot be charged.
Leaving out HSN or accounting code, place of supply or reverse charge status in the list of contents.
Students list only name, date and amount.
Fix: Use a fixed order: supplier, number, date, recipient, code, description, quantity, values, tax rates and amounts, place of supply, delivery address, reverse charge, signature.
Assuming the invoice number can be any length or repeat in the year.
The rule on serial numbering is skipped.
Fix: Remember: consecutive, unique for the financial year, up to 16 characters made of letters, numerals, hyphen or slash.

Worked examples

Example 1

Sharma Textiles Pvt. Ltd., Surat, a regular registered supplier, sends goods to a customer in Jaipur by road. The goods leave the factory on 12 August. By when must the tax invoice be issued? How many copies are needed and who gets each?

Show the solution

The supplier is a regular registered person, so a tax invoice is required.
The supply is of goods and involves movement.
For goods involving movement, the invoice must be issued before or at the time of removal of goods.
Removal is on 12 August, so the invoice must be issued on or before 12 August.
For goods, Rule 46 requires triplicate: Original for Recipient, Duplicate for Transporter, Triplicate for Supplier.

Answer: Issue the tax invoice on or before 12 August, before the goods leave. Prepare three copies: original for the customer, duplicate for the transporter and triplicate for Sharma Textiles.

Example 2

Kaveri Consultants, a registered firm in Chennai, completes a management consulting service on 20 March. It is not a bank, insurer or NBFC. State the last date for issuing the tax invoice, the number of copies, and any four particulars required on the invoice.

Show the solution

The supply is a service by a regular registered person, so a tax invoice is required.
The time limit for services is 45 days from the date of supply.
Days left in March after 20 March: 11 days (21 to 31 March).
Remaining days: 45 − 11 = 34 days, which fall in April (30 days) and then 4 days in May.
So day 45 is 4 May. The last date is 4 May.
For services the invoice is in duplicate: Original for Recipient and Duplicate for Supplier.
Four particulars: name, address and GSTIN of supplier; invoice serial number and date; accounting code (SAC) and description of the service; taxable value with rate and amount of CGST, SGST or IGST.

Answer: The invoice must be issued on or before 4 May. Two copies are needed: original for the recipient and duplicate for the supplier. Particulars include supplier details, invoice number and date, SAC with description, and taxable value with tax rate and amount.

Exam tips

Write goods and services side by side in a two-line comparison. Examiners give marks for each correct point on time and copies.
In date questions, show the day count. Even if you slip, step marks may follow.
Do not skip the composition and exempt supply exception. It is a favourite one-mark point.
In contents questions, group the particulars under supplier, recipient, goods or services, tax and signature. A grouped list looks complete and is easier to check.
For MCQs, read whether the question says goods or services before you pick the number of copies or days.

Practice questions from Tax Invoice - Electronic Way Bill

Tax Invoice: Meaning, Time and Contents in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Tax Invoice: Meaning, Time and Contents: frequently asked questions

What is the time limit to issue a tax invoice for services?

The tax invoice for services must be issued within 45 days from the date of supply. For an insurer, banking company, financial institution or NBFC, the limit is 30 days.

How many copies of a tax invoice are required under GST?

For goods, three copies are required: original for the recipient, duplicate for the transporter and triplicate for the supplier. For services, two copies are required: original for the recipient and duplicate for the supplier.

What are the mandatory particulars of a tax invoice?

These include supplier name, address and GSTIN, a unique serial number, date, recipient details, HSN or accounting code, description, quantity, value, tax rate and amount, place of supply, reverse charge status and signature. Learn them in that order.

Does a composition dealer issue a tax invoice?

No. A person paying tax under the composition scheme issues a bill of supply and cannot collect tax from the recipient. An exempt supply is also covered by a bill of supply.