GST on Works Contract: Rates, ITC Rules, and Why Builders Get It Wrong

Works contract is a composite supply of goods and services — think construction of a building, renovation, installation, or any project where both materials and labour are involved. GST treats it as a supply of service. But the rate, the ITC availability, and the TDS obligation depend heavily on who the customer is and what is being built. Getting it wrong is expensive.

What Is a Works Contract Under GST?

Section 2(119) of the CGST Act defines works contract as a contract for building, construction, fabrication, completion, erection, installation, fitting out, improvement, modification, repair, maintenance, renovation, alteration, or commissioning of any immovable property — where transfer of property in goods is involved in the execution of such contract.

This definition is wide. It covers a civil contractor building a road, an interior designer fitting out an office, and an MEP contractor installing HVAC systems. The common thread: work on immovable property with materials supplied.

GST Rates on Works Contract — The 12% vs 18% Split

18 percent GST applies to works contracts for commercial and industrial construction, repair, renovation, and maintenance. This is the standard rate for most private sector works contracts.

12 percent GST applies to works contracts for: (a) construction of affordable residential apartments (carpet area up to 60 sq. metres in metro cities or 90 sq. metres in other cities, value up to Rs 45 lakh), (b) works contracts where the recipient is the Central Government, State Government, Union Territory, or local authority for the construction of civil structures — excluding commercial purposes.

5 percent GST (no ITC) applies to construction of residential apartments other than affordable housing, sold before obtaining completion certificate.

The Blocked ITC Problem — Section 17(5)(c) and (d)

Section 17(5) of the CGST Act blocks ITC on works contract services when they are used for construction of an immovable property — even if it will be used in your business. Sub-clause (c) blocks ITC on works contract services for construction of immovable property (other than plant and machinery). Sub-clause (d) blocks ITC on goods or services received for construction of immovable property on own account.

Practical example: A manufacturing company builds a factory shed. The works contractor charges 18 percent GST. The manufacturing company cannot claim ITC on this GST — even though the shed will be used 100 percent for taxable manufacturing. This is a blocked ITC under Section 17(5)(d).

Exception: If the immovable property is itself a supply — meaning you are a real estate developer selling units or a contractor building for another — then the ITC is available. The block applies to the end-user building for own use.

TDS Under GST on Works Contract — Section 51

If your customer is a Government department, PSU, local body, or notified entity, they are required to deduct TDS at 2 percent (1 percent CGST plus 1 percent SGST) on payments above Rs 2.5 lakh for any single contract. This TDS appears in your GSTR-2B as credit in your Electronic Cash Ledger — it is not ITC. You must utilise it within two years.

HSN Code for Works Contract

Works contract services fall under SAC 9954. Sub-categories include 995411 (construction of residential buildings), 995412 (construction of other buildings), 995421 (general construction of civil engineering works). Use the correct 6-digit SAC in your tax invoice — wrong HSN attracts notices under Rule 46.

Key Takeaway

Works contract GST has three moving parts — the correct rate, the ITC availability check under Section 17(5), and TDS deduction if the client is a government entity. Get all three right. A wrong rate or wrongly claimed ITC on immovable property construction leads to demand with interest and penalty. For more GST guides and tools, visit gstvala.com. Consult your CA for project-specific advice.