Indirect Tax Laws · Supply under GST

Time of Supply of Services under Section 13 CGST Act

Updated 5 October 2026 · Fact-checked

Time of supply of services under section 13 of the CGST Act fixes the date on which GST liability arises. For forward charge, it is the earlier of the invoice date (if issued within 30 days) and the payment date. For reverse charge, it is the earlier of the payment date and the day after 60 days from the invoice. Otherwise, residual rules apply.

Understand Time of Supply of Services

Time of supply is the date on which GST becomes payable on a service. It decides which month's return you report the supply in, which rate of tax applies, and when interest starts if you pay late. Examiners test it with dates, so you must be exact.

Under forward charge, the supplier pays the tax. The law looks at three dates: the invoice date, the date of payment, and the date the service was provided. The supplier must issue the invoice within the prescribed period, which is 30 days from the date of supply of service. For insurers, banking companies and financial institutions (including NBFCs) it is 45 days. If the invoice is on time, the earlier of invoice date and payment date is the time of supply. If the invoice is late, the earlier of the date of provision of service and the payment date is the time of supply. Apply this test separately to each payment. Under forward charge, the date of receipt of payment is the earlier of the date the payment is entered in the supplier's books of account and the date it is credited to the supplier's bank account.

The date the recipient shows the receipt of service in his books of account is the third limb of the forward charge rule in section 13(2). It applies only where neither the on-time invoice rule nor the late invoice rule applies. It is not a step you apply in every question. First ask whether the invoice was on time, then apply the matching earlier-of rule. Do not confuse this books-entry limb with the residual rule described below, which is a different rule for a different situation.

Under reverse charge, the recipient pays the tax. The time of supply is the earlier of two dates: the date of payment, and the date immediately following 60 days from the date of the supplier's invoice or other document. The date of payment is the earlier of the date of entry in the recipient's books and the date the payment is debited in his bank account. If the time of supply cannot be determined under either of these two tests, it is the date of entry in the recipient's books. Separately, where the supplier is an associated enterprise located outside India, the time of supply is the earlier of the date of entry in the recipient's books and the date of payment.

There is also a separate rule for vouchers: the date of issue of the voucher if the supply is identifiable then, otherwise the date of redemption. A residual rule applies where the rules above cannot fix the date. Then the time of supply is the due date of the periodical return where one is to be filed, or otherwise the date on which the tax is paid. Section 14 then decides which rate applies when the rate of tax changes. Note that, unlike goods, advance payment for services is a trigger: tax arises on the advance, to the extent of the payment.

Key rules to remember

Forward charge: invoice issued within the prescribed period: Time of supply = earlier of (date of invoice, date of receipt of payment); Prescribed period is 30 days from the date of supply of service (45 days for insurers, banks and financial institutions including NBFCs).
Forward charge: invoice not issued within the prescribed period: Time of supply = earlier of (date of provision of service, date of receipt of payment); Late invoicing pulls the liability back to the date of service. Apply it separately to each payment.
Forward charge: books-entry limb of section 13(2): Time of supply = date the recipient shows receipt of service in his books of account; Used only where neither the on-time invoice rule nor the late invoice rule applies. It is not a separate third step in every question, and it is not the residual rule.
Date of receipt of payment (forward charge): Earlier of (date payment is entered in the supplier's books of account, date credited to the supplier's bank account); These are the supplier's books and bank account. Tax arises only to the extent covered by the invoice or the payment.
Reverse charge: Time of supply = earlier of (date of payment, day immediately following 60 days from date of supplier's invoice); Date of payment = earlier of the date of entry in the recipient's books and the date of debit in his bank account. If the time of supply cannot be determined under these two tests, use the date of entry in the recipient's books.
Associated enterprise outside India: Time of supply = earlier of (date of entry in recipient's books, date of payment); This is a separate rule. The 60-day rule is not used for this case.
Vouchers: Date of issue of voucher if supply is identifiable at that time; otherwise date of redemption; Single-purpose versus multi-purpose voucher logic follows this rule.
Residual rule: Due date of periodical return if one is to be filed; otherwise date on which the tax is paid; Used only when the forward charge, reverse charge and voucher rules cannot fix the time of supply. It is different from the books-entry limb of the forward charge rule.
Change in rate of tax (section 14): Rate = rate in force on the time of supply; For a service supplied before the change, if both invoice and payment fall after the change, the new rate applies. For a service supplied after the change, if both invoice and payment fall before the change, the old rate applies. For mixed cases, apply the section 14 text carefully.

How to solve Time of Supply of Services questions

Use this order for any time of supply question on services. Write the dates down in a column before you apply any rule.

1Identify who pays the tax: supplier (forward charge) or recipient (reverse charge). Check whether the supplier is an associated enterprise outside India.
2List every date in the case: date of provision of service, invoice date, date of payment in books, date of credit or debit in bank, and the date the recipient records the service.
3Fix the date of payment. Under forward charge, it is the earlier of the entry in the supplier's books and the credit in the supplier's bank account. Under reverse charge, it is the earlier of the entry in the recipient's books and the debit in his bank account. If payment is in parts, treat each part separately.
4For forward charge, check whether the invoice was issued within 30 days of the service (45 days for banks, insurers and financial institutions). Then apply the earlier-of rule that matches. Use the date the recipient shows the service in his books only if neither invoice rule applies.
5For reverse charge, count 60 days from the invoice date, take the next day, and compare it with the payment date. Choose the earlier.
6If the case involves a voucher, use the voucher rule. Use the residual rule only if none of the other rules can fix the date.
7If the rate of tax changes in the case, apply section 14 to the time of supply you found, and state which rate applies.
8Write the conclusion with the exact date and the reason in one line, in provision-fact-conclusion form.

Quickest way: Three-question shortcut

When to use it: Use in the MCQ section or when a long written problem has many dates and little time.

Ask: who pays the tax? Forward charge uses 30 days; reverse charge uses 60 days.
Forward charge: was the invoice within 30 days? If yes, pick the earlier of invoice and payment. If no, pick the earlier of service date and payment.
Reverse charge: compute the day after 60 days from the invoice. Pick the earlier of that date and the payment date.
Tick off advances: any advance for services creates a time of supply on the advance date, for the amount received.
Check for a rate change last, and apply the rate on the date you chose.

Common mistakes in Time of Supply of Services

Using the invoice date as the time of supply even when the invoice was issued after 30 days.
Students remember 'invoice or payment' and forget the condition on the prescribed period.
Fix: Always count 30 days from the date of service first. A late invoice moves the test to the date of service and payment.
Applying the 60-day reverse charge rule under forward charge, or the 30-day rule under reverse charge.
The two periods are similar and are learnt together.
Fix: Tie each number to the payer: supplier pays, 30 days; recipient pays, 60 days.
Counting the 60th day itself as the date for reverse charge.
The words 'immediately following 60 days' are read loosely.
Fix: Count 60 days from the invoice date, then add one day. That next day is the date to compare with payment.
Ignoring advances for services, as is done for goods.
Students carry the goods rule into services.
Fix: For services, receipt of payment is a time of supply trigger. Tax arises on the advance to the extent of the amount received.
Taking the bank date alone as the payment date.
Students assume payment means money in the bank.
Fix: Take the earlier of the date of entry in the books and the date of bank credit (or debit, under reverse charge).
Applying the new rate just because the invoice is dated after the rate change.
Section 14 conditions on supply date, invoice and payment are not checked together.
Fix: Find the time of supply first, then use the section 14 cases. List the supply date, invoice date and payment date against the date of change.

Worked examples

Example 1

Case: Brightline Consultants, a registered firm, completes an advisory service for Meera Ltd on 10 March. The total value is ₹5,00,000 plus GST. Meera Ltd pays an advance of ₹1,00,000, which is entered in the firm's books and credited to its bank on 20 February. The firm issues the invoice for the full value on 25 April. The balance is received on 30 April. Meera Ltd is not under reverse charge. Determine the time of supply for each part.

Show the solution

Provision: this is forward charge, so the supplier pays the tax. The invoice must be issued within 30 days of the service.
Facts: the service was provided on 10 March. The 30-day period ended on 9 April. The only invoice in the case is dated 25 April, so it is late.
Rule for a late invoice: the time of supply is the earlier of the date of provision of service and the date of receipt of payment. Apply this rule separately to each payment.
Advance of ₹1,00,000: the books entry and the bank credit are both 20 February, so the date of receipt of payment is 20 February. This is earlier than 10 March. The advance falls before the service, so the earlier-of test picks the payment date under either invoice rule, and the late invoice does not change this. The time of supply for this part is 20 February.
Balance of ₹4,00,000: the payment date is 30 April (assumed same in books and bank), and the provision date is 10 March. The earlier is 10 March. The time of supply for this part is 10 March.

Answer: Time of supply is 20 February for ₹1,00,000 (advance) and 10 March for the balance ₹4,00,000, because the invoice was issued after the 30-day limit and the earlier of the provision date and the payment date is taken for each payment.

Example 2

Case: Kavya Traders, a registered company, receives legal services from an advocate, an unregistered individual, on which tax is payable under reverse charge. The advocate's invoice is dated 10 February 2027. Kavya Traders records the payment in its books on 20 April 2027, and the bank debits the amount on 25 April 2027. Determine the time of supply.

Show the solution

Provision: this is reverse charge, so the time of supply is the earlier of the date of payment and the day immediately following 60 days from the date of the supplier's invoice.
Date of payment: the books entry is 20 April 2027 and the bank debit is 25 April 2027. The earlier is 20 April 2027.
60-day date: count from 10 February 2027. The remaining days of February 2027 are 18 (to 28 February). Add 31 days of March to get 49. Add 11 days of April to get 60, which is 11 April 2027.
The day immediately following is 12 April 2027.
Compare: 12 April 2027 is earlier than 20 April 2027.

Answer: The time of supply is 12 April 2027.

Exam tips

Write the dates in a small list first. Most marks are lost by comparing the wrong dates, not by knowing the wrong rule.
State the condition each time, for example 'invoice issued within 30 days' or 'reverse charge, so 60 days'. Examiners mark the provision as well as the answer.
When payment is in instalments, split the supply and decide the time of supply for each part separately.
In MCQs, check whether the supplier is a bank, insurer or financial institution. The invoice period for them is 45 days.
If a rate change appears, find the time of supply first, then apply section 14 to the rate. Say which rate applies and why.

Practice questions from Supply under GST

Time of Supply of Services in other exams

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

Time of Supply of Services: frequently asked questions

What is the time of supply of services under section 13 CGST?

It is the date on which the liability to pay GST on a service arises. Section 13 gives separate rules for forward charge and reverse charge, with special rules for vouchers and a residual case. You must apply the rule that matches the facts.

What happens if the invoice for a service is issued after 30 days?

The invoice date is no longer used. The time of supply becomes the earlier of the date of providing the service and the date of receipt of payment. For banks, insurers and financial institutions, the period is 45 days.

How is time of supply of services decided under reverse charge?

It is the earlier of the date of payment and the day immediately following 60 days from the date of the supplier's invoice. If this cannot be applied, the date of entry in the recipient's books is used. A different rule applies to associated enterprises outside India.

Is advance received for services taxable at once?

Yes. Receipt of payment is one of the dates considered for services, so tax arises on the advance to the extent of the amount received. This is different from goods.

Which rate applies if the rate of tax changes?

The rate in force on the time of supply applies. Section 14 sets out the cases that depend on the dates of supply, invoice and payment relative to the change.