GST on Buying a Flat in Chennai: When You Pay 1%, 5% or Nothing
GST hits only under construction flats, at 1% or 5% without input tax credit, while ready to move and resale homes are nil. Here is how to tell which you are buying.
A Chennai buyer comparing two similar flats in Perumbakkam in September 2026 could not understand why one quote carried a 5 percent tax line and the other carried none. Same locality, same size, almost the same price. The difference was not a discount or a scam. One flat was still under construction and the other was ready to move in, with its completion certificate already issued. That single fact decided whether goods and services tax applied at all. Understanding when GST applies, and at what rate, can change your total outgo by several lakh.
The short answer. GST applies only to under construction homes. For an under construction flat you pay 1 percent without input tax credit if it qualifies as affordable, and 5 percent without input tax credit otherwise, as set by the GST Council and effective from 1 April 2019. A ready to move flat where the builder already holds the completion certificate or first occupation attracts no GST, and so does a resale flat or a plot of land. The trade off: the headline rate on an under construction home looks small, but because the builder gets no input tax credit, that cost is baked into the base price you negotiate, so you cannot simply assume a GST free property is cheaper overall.
Do you pay GST when buying a flat in Chennai?
You pay GST only if the flat is under construction when you buy it. Under the goods and services tax framework, the sale of a completed building, one for which the completion certificate has been issued or first occupation has already taken place, is treated as a transaction in immovable property and falls outside GST. The same is true of a resale flat bought from an existing owner and of a plain plot of land, since the sale of land is outside the scope of GST.
This is why the stage of construction, not the locality or the builder's brand, decides your tax. If you buy early in a project while it is still being built, you are buying a service of construction, and GST attaches to it. If you wait until the project is complete and the certificate is in hand, you are buying finished property, and GST does not apply. Neither route is automatically cheaper, but knowing which bucket your purchase falls into tells you whether to expect a tax line at all.
What are the GST rates, 1 percent or 5 percent?
For an under construction residential flat there are two rates, both charged without input tax credit. According to the GST Council's FAQ on the real estate sector, construction of an affordable residential apartment is taxed at 1 percent without input tax credit, and construction of any other residential apartment is taxed at 5 percent without input tax credit, both effective from 1 April 2019. These are effective rates already computed after a deduction for the value of the land, so you apply them to the total consideration rather than adding a separate land tax.
The practical upshot for a Chennai buyer is simple arithmetic once you know your category. A flat that qualifies as affordable carries one fifth of the tax of one that does not, so the affordable threshold is worth checking carefully before you accept a 5 percent line on your cost sheet. The rate is set nationally, so it does not vary between Chennai, Coimbatore or any other part of Tamil Nadu.
What counts as an affordable flat in Chennai?
Affordable status depends on two tests that must both be met, size and price. The GST Council defines an affordable residential apartment as one with a carpet area up to 60 square metres in metropolitan cities and up to 90 square metres in other cities and towns, where the gross amount charged by the builder is not more than 45 lakh rupees. Both conditions apply together, so a flat that is small but priced above 45 lakh, or cheap but larger than the carpet area limit, does not qualify.
Chennai is treated as a metropolitan city under the notification, so the carpet area ceiling for affordable status here is 60 square metres, not 90. That makes the affordable category genuinely tight in much of the city, where ticket sizes often cross 45 lakh. Note that the limit is on carpet area, the usable area within your walls, not the super built up area quoted in brochures, so ask for the carpet area figure in writing before deciding which rate should apply.
Why does no input tax credit matter to your price?
No input tax credit means the builder cannot offset the GST paid on cement, steel and services, so that cost flows into your price. Under the rates effective from April 2019, developers lost the ability to claim input tax credit on under construction residential projects. The GST they pay on materials and inputs therefore becomes a cost they absorb, and in practice it is recovered through the base selling price rather than shown to you.
For you as a buyer, this has an important consequence. A ready to move flat may carry no GST line at all, but its price already reflects the builder's absorbed input taxes. An under construction flat shows a visible 1 percent or 5 percent, but its base price may be pitched differently. The honest comparison is total outgo, including stamp duty and registration, not just whether a GST line appears. For the registration side of a Chennai purchase, see our guide to Tamil Nadu guideline value and registration charges.
When is a flat completely free of GST?
Several common situations carry no GST at all, and recognising them prevents you from paying tax you do not owe. The table below sets out the main scenarios a Chennai buyer meets, the GST treatment, and the key condition that decides it.
| Scenario | GST treatment | Deciding condition | Input tax credit |
|---|---|---|---|
| Under construction, affordable | 1 percent | Carpet area up to 60 sq m and price up to 45 lakh | Not available |
| Under construction, other | 5 percent | Does not meet both affordable tests | Not available |
| Ready to move with certificate | Nil | Completion certificate or first occupation before sale | Not applicable |
| Resale flat from an owner | Nil | Sale of completed, previously occupied property | Not applicable |
| Plot of land only | Nil | Sale of land is outside GST | Not applicable |
The single most important line is the ready to move row. If a builder tries to add GST to a flat for which the completion certificate has already been issued, that is a line to question, because a completed property is outside GST. Keep a copy of the completion or occupancy certificate, since it is both your proof of a legal, finished home and the document that settles the GST question.
How do you compute the GST on your flat?
Once you know the rate, the calculation is straightforward multiplication on the price. Take a non affordable under construction flat in Chennai priced at 80 lakh. At 5 percent, the GST is 4 lakh, payable in line with your construction linked instalments. Now take a genuinely affordable flat of 55 square metres carpet area priced at 44 lakh, which meets both the size and value tests. At 1 percent, the GST is just 44,000, a difference of more than 3.5 lakh purely from the category.
Because GST on an under construction flat is usually collected alongside each payment stage, you pay it gradually as the slabs are cast, not in one lump at the start. Build the full GST figure into your budget from day one, and sit it next to your stamp duty, registration and loan costs so you see the complete picture. A GST free ready flat is not a saving if its base price is higher, which is exactly why total cost, not the tax line alone, should guide the decision. For another tax you will meet at purchase, read our explainer on TDS on a property purchase under Section 194-IA.
Your seven step GST checklist for a Chennai flat
- Confirm in writing whether the flat is under construction or ready, since that alone decides if GST applies.
- If it is ready, ask for the completion or occupancy certificate, because a completed home is outside GST.
- For an under construction flat, ask whether the builder is charging 1 percent or 5 percent and why.
- Check the carpet area against the 60 square metre limit and the price against the 45 lakh cap for affordable status.
- Remember that both the size and price tests must be met together for the 1 percent rate.
- Treat the quoted rate as final, since builders cannot claim input tax credit and will not pass any back.
- Compare total outgo, including GST, stamp duty and registration, before concluding which flat is cheaper.
GST on a home sounds complicated, but for a buyer it collapses into a few clear questions: is the flat under construction, does it meet both affordable tests, and does the builder hold a completion certificate. Answer those three and you know whether you owe nothing, 1 percent or 5 percent. In a city like Chennai, where ticket sizes and carpet areas sit right around the affordable thresholds, those answers can be worth several lakh, so settle them in writing before you sign.
Is GST charged on a ready to move flat in Chennai?
No. A ready to move flat for which the builder has already obtained the completion certificate or where first occupation has taken place is outside GST. GST applies only to under construction homes. If a seller adds GST to a completed, certificate in hand flat, question it, and keep the completion or occupancy certificate as your proof.
What is the GST rate on an under construction flat?
Construction of an affordable residential apartment is taxed at 1 percent without input tax credit, and any other residential apartment at 5 percent without input tax credit, as set by the GST Council and effective from 1 April 2019. These effective rates already account for a deduction towards the value of the land in the price.
What makes a Chennai flat affordable for the 1 percent GST rate?
Two tests must both be met. The carpet area must be up to 60 square metres, since Chennai is a metropolitan city, and the gross amount charged by the builder must not exceed 45 lakh rupees. A flat priced above 45 lakh, or larger than 60 square metres, falls into the 5 percent category.
Does the builder pass on input tax credit to me?
No. Under the rates effective from April 2019, developers cannot claim input tax credit on under construction residential projects, so there is nothing to pass on. The GST a builder pays on materials and services becomes a cost absorbed into the base price. That is why you should compare the total price rather than only the visible tax line.
Last updated 2026-10-01. PropNewz Team.
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