Start with the contract, then calculate the deduction
For a covered government deductor, GST TDS generally arises when the taxable value of supply under the contract exceeds ₹2,50,000. Once the contract qualifies, a smaller individual payment or credit can still attract deduction. Exclude separately indicated GST and cess from the deduction base, and first test the statutory location exception. The usual combined deduction is 2%: 1% CGST plus 1% SGST/UTGST for an eligible intra-State supply, or 2% IGST for an eligible inter-State supply.
This article concerns ordinary taxable procurement by a government department already within section 51, assuming no transaction-specific notification exclusion. It does not treat every private purchaser as a deductor or attempt to catalogue all specially notified classes. Check the payer’s legal status and current applicable exclusions before applying the calculations. Law checked on 23 October 2026.
Legal framework and the order of review
Read CGST Act sections 39(3) and 51, IGST Act section 20 and CGST Rule 66 together. Section 51 establishes the deduction trigger and invoice-tax exclusion; the corresponding State/UT provision supplies the other intra-State component. IGST Act section 20 supplies the inter-State deduction rate. Rule 66 governs GSTR-7 and the related certificate mechanism.
The CBIC government-department TDS SOP dated 18 February 2019 usefully illustrates contract and base calculations. Its historical return, certificate and portal descriptions must not override later law. In particular, do not repeat an old statement that a registered TDS deductor has no return obligation in a month without deductions: the current section 39(3) expressly requires a return for every calendar month whether or not deductions were made.
| Review stage | What to test | What this prevents |
|---|---|---|
| Deductor status | Covered government body and applicable notification position | Treating an ordinary purchaser as automatically liable |
| Contract threshold | Total taxable supply value, excluding GST/cess | Testing only the current invoice or including tax to cross the limit |
| Location condition | Supplier location, place of supply and recipient registration | Overlooking section 51’s specific no-deduction proviso |
| Deduction and reporting | Payment/credit base, correct tax heads and monthly return | Using invoice tax as the TDS amount or missing a nil-month return |
The threshold is strict and contract-specific
Exactly ₹2,50,000 does not exceed ₹2,50,000. An invoice total above that amount may still fail the threshold once GST is excluded. Conversely, a qualifying contract is not broken into independent threshold tests for each instalment. Maintain a contract reference on every bill so accounts payable can connect a small bill to the complete contracted taxable value.
Where a contract genuinely includes taxable and exempt supplies, isolate the taxable value using a supported classification and allocation. The SOP illustrates why a large overall contract containing only a below-threshold taxable component does not meet the taxable-contract test. This is not permission to label taxable amounts exempt or artificially divide one contract into several purchase orders.
Two genuinely independent contracts with the same vendor are not automatically one contract solely because the vendor is common. But an administrative document number is not conclusive: examine the commercial scope, amendments and actual contract obligations. If the scope changes, revisit the threshold against the legally operative contract rather than silently preserving the original flag.
Payment or credit, tax-exclusive base and location exception
Section 51 refers to payment made or credited to the supplier. A file should therefore check book credits as well as bank releases. Do not postpone analysis until the final cash settlement. Use the supply value after excluding CGST, SGST/UTGST, IGST and cess indicated in the invoice. The supplier’s output GST rate and the GST TDS rate answer different questions; invoice GST is not itself the deduction base.
The no-deduction proviso applies where the supplier’s location and place of supply are in the same State or Union territory and that State/UT differs from the recipient’s registration State/UT. Preserve all three locations. “Vendor is outside our State” is too crude a rule: an inter-State procurement can require IGST TDS, while the particular three-location pattern can prohibit this deduction.
The numerical illustrations assume the ordinary section 51 mechanism applies, no special exemption, and no unrelated retention, income-tax withholding or contractual recovery. Their stated invoice GST amounts are assumptions for arithmetic, not a classification opinion that the goods or services bear a particular output rate.
Monthly payment, GSTR-7 and supplier reconciliation
Tax deducted ordinarily has to be paid to the Government within ten days after the end of the deduction month, and Rule 66 ordinarily requires GSTR-7 by the tenth day of the succeeding month. Check any valid period-specific extension rather than assuming one. The current monthly-return obligation also covers a month with zero deductions; it does not itself create tax on a non-deductible payment.
Reconcile supplier GSTIN, contract, invoice/credit, deduction amount, tax head, Government payment and return acknowledgement. Rule 66 provides the related GSTR-7A certificate mechanism, while the supplier’s TDS credit is dealt with through the electronic cash ledger after the applicable validation. It is not ordinary purchase ITC. Incorrect GSTIN or tax-head allocation can therefore obstruct usable supplier credit even when the deductor’s cash total is right.
Worked illustrations
These illustrations use fictional facts and expressly stated assumptions. Amounts are Indian rupees unless a different currency or unit is specified. They are independent examples, not findings about any actual client.
Illustrative example 1: Invoice total exceeds the limit but taxable value does not
A covered department has one contract with taxable value ₹2,50,000 and separately indicated GST of ₹45,000. The total is ₹2,95,000. Because the taxable contract value is exactly, not above, ₹2,50,000, section 51 TDS is zero on these facts.
Illustrative example 2: A small instalment under a qualifying contract
The taxable contract value is ₹6,00,000. An intra-State instalment invoice has base ₹1,00,000 and GST ₹18,000. Deduct ₹1,000 CGST and ₹1,000 SGST, total ₹2,000. The supplier receives ₹1,18,000 − ₹2,000 = ₹1,16,000, ignoring other deductions. The instalment’s smaller size does not remove TDS.
Illustrative example 3: Taxable and exempt components within one contract
Assume a defensible allocation of a ₹5,00,000 contract between ₹3,00,000 exempt supplies and ₹2,00,000 taxable supplies. The taxable component does not exceed the threshold, so no section 51 deduction arises on those facts. If instead taxable value is ₹3,00,000 and exempt value ₹2,00,000, the taxable component qualifies; a payment/credit of the entire taxable base attracts ₹6,000 combined TDS. Do not deduct on the exempt ₹2,00,000.
Illustrative example 4: Independent contracts with a common vendor
Two genuinely independent contracts have taxable values ₹1,80,000 and ₹1,70,000. Their aggregate vendor total is ₹3,50,000, but neither contract exceeds ₹2,50,000. GST TDS is zero under the stated facts. Retain the independent scopes; the result should not be applied to an artificial split of a single contract.
Illustrative example 5: Inter-State procurement
Supplier location is State A, place of supply is State B and the recipient’s deductor registration is in State B. A qualifying invoice has base ₹4,00,000 and IGST ₹72,000. With no applicable exemption, IGST TDS is ₹4,00,000 × 2% = ₹8,000. Net payment is ₹4,72,000 − ₹8,000 = ₹4,64,000.
Illustrative example 6: The location proviso overrides a qualifying value
Supplier location and place of supply are both Delhi, while the recipient’s relevant deductor registration is in Haryana. Even with taxable contract value ₹5,00,000, the specified section 51 proviso means GST TDS is zero. This conclusion does not decide any separate income-tax withholding requirement.
Illustrative example 7: Deduction-month calendar
A covered department deducts ₹5,000 during October 2026. Without a valid extension, the ordinary Government-payment and GSTR-7 deadline is 10 November 2026. If November has no deductions, the registered deductor still has a November GSTR-7 obligation, ordinarily due 10 December 2026; the nil-month tax amount is zero.
Ten-step verification table
| Step | Verification | Evidence to retain |
|---|---|---|
| 1 | Confirm covered deductor status and relevant registration | Constitution record, notification analysis and deductor GSTIN |
| 2 | Check transaction-specific exclusions before computing | Supply facts and current applicable notification record |
| 3 | Identify the operative contract and all amendments | Executed contract, scope and change orders |
| 4 | Reconcile taxable contract value excluding GST and cess | Value schedule and supported taxable/exempt allocation |
| 5 | Apply the strict greater-than threshold | Contract-level ₹2,50,000 eligibility working |
| 6 | Record all three locations and the proviso conclusion | Supplier location, place of supply and recipient registration |
| 7 | Inspect credits as well as payment releases | Ledger posting, invoice and disbursement dates |
| 8 | Compute the base and allocate correct TDS tax heads | Tax-exclusive base, rate calculation and bill settlement |
| 9 | Pay and furnish the monthly return, including nil months | Challan, GSTR-7 acknowledgement and deadline/extension check |
| 10 | Reconcile supplier cash-ledger credit and certificate details | GSTIN match, return reconciliation and GSTR-7A record |
Sixteen practitioner FAQs
1. Does every purchaser deduct GST TDS?
No. Deductor status is a separate statutory and notification test. This guide assumes an ordinary covered government department; private or specially notified categories require their own status examination.
2. Is ₹2.5 lakh an invoice threshold?
No. Test taxable value under the contract. A payment or credit below that amount can attract deduction when it belongs to a qualifying contract.
3. What happens at exactly ₹2,50,000?
The value does not exceed the statutory threshold. Do not convert a strict greater-than test into a greater-than-or-equal test.
4. Can separately indicated GST push a contract across the threshold?
No. Exclude invoice GST and cess for this purpose. Distinguish the tax-inclusive cash payable from the taxable supply value being tested.
5. How should an exempt component be handled?
Establish that it is genuinely exempt and identify the taxable component of the contract. Keep the classification and allocation evidence rather than relying on an unsupported ledger description.
6. Are all contracts with one supplier combined?
A common vendor does not automatically combine genuinely independent contracts. Equally, several purchase-order numbers do not establish independence if they implement one underlying contract.
7. Is deduction deferred until cash payment?
Section 51 addresses amounts paid or credited. Review the accounting credit event rather than assuming a bank debit is always the first relevant event.
8. Is the deduction 2% CGST plus 2% SGST?
No. The ordinary combined intra-State deduction is 1% CGST plus 1% SGST/UTGST. The ordinary inter-State deduction is 2% IGST.
9. Is TDS calculated on invoice GST?
No. Calculate it on the relevant supply value after excluding GST and cess indicated in the invoice. Output GST and TDS have different functions.
10. Does every out-of-State supplier fall within the exception?
No. The proviso requires supplier location and place of supply to be in the same State/UT, different from the recipient’s registration State/UT. Document the complete pattern.
11. What is the ordinary GSTR-7 deadline?
The tenth day of the succeeding month under Rule 66, subject to any legally valid extension for the relevant period. Government payment also ordinarily follows the ten-day month-end rule.
12. Is a nil-month GSTR-7 still required?
Yes for a registered TDS deductor under current section 39(3). Older guidance suggesting otherwise must be read against the amended law.
13. Does a nil return mean every payment was exempt?
No. A zero-deduction month can have several explanations. Retain the contract, threshold and location analysis for payments that did occur.
14. Does the supplier claim this as ordinary ITC?
TDS credit operates through the electronic cash ledger under the relevant validation mechanism. Do not reconcile it as ordinary input tax credit from a purchase invoice.
15. Can the department issue an improvised certificate instead?
Follow the prescribed return and GSTR-7A mechanism. A separate payment advice can explain a deduction but does not replace the statutory records.
16. Does a zero GST TDS conclusion settle income-tax TDS?
No. The two regimes have separate triggers and conditions. Show separate withholding conclusions on the bill so that a GST exception is not incorrectly extended to income tax.
Working-paper organisation
Keep the source documents, calculation and final conclusion together for the same entity and period. If using assureTax or other assureOffice tools, use only confirmed available functions and retain this evidence with the output.
Conclusion
A defensible GST TDS file links each payment or credit to the taxable contract value, the three-location test and the correct tax-exclusive base. Keep the current monthly GSTR-7 obligation separate from whether any deduction arose in that month.