An under construction flat looks cheaper by a third, and the build period decides how much of that you actually keep. On a Rs 1.25 crore gap, a three year build leaves you Rs 68.6 lakh ahead. A six year build leaves Rs 24.7 lakh. GST, rent paid while you wait and interest on drawn instalments do the eating, and they scale with time rather than price. This covers the full arithmetic, the tax rules that decide it, and what a two year slip does to the answer.
Written by Mansi Joshi, Marketing Intelligence Lead, ZYN33 Investment Desk. Reviewed by Ritesh Arora, Founder, ZYN33 and Strata Capital Holdings, Gurugram. Advising on Gurugram residential capital allocation since 2023, with mandates ranging from Rs 3 Cr to Rs 50 Cr. Published 18 June 2026. Last reviewed 7 September 2026.
Disclosure: ZYN33 distributes residential projects in Gurugram and is paid a transaction fee when a purchase completes, including on projects we discuss with you. We do not give tax advice. This post is general information. Take it to your chartered accountant.
An under construction flat looks cheaper by about a third. How much of that you keep depends almost entirely on one variable: how long the build takes.
On a Rs 1.25 crore gap, a three year build leaves you Rs 68.6 lakh ahead. A six year build leaves Rs 24.7 lakh. Same discount, same corridor, four fifths of the advantage gone. Anyone answering ready to move vs under construction with a single percentage is answering a question that has a different answer every year you wait.
Between 20 and 55 percent, decided by the build period. Here is the arithmetic with every input stated, so you can change them.
Take a ready unit at Rs 3.75 Cr against an under construction equivalent at Rs 2.5 Cr. That is a Rs 1.25 crore gap, or 33 percent off the ready price. Three costs sit on top of the under construction option, and all three scale with time rather than with price.
|
Build period |
GST at 5 percent |
Rent while you wait |
Interest on instalments |
Total overlay |
Net saving kept |
|
3 years |
Rs 12.5 L |
Rs 21.6 L |
Rs 22.3 L |
Rs 56.4 L |
Rs 68.6 L, 55 percent |
|
4 years |
Rs 12.5 L |
Rs 28.8 L |
Rs 29.8 L |
Rs 71.0 L |
Rs 54.0 L, 43 percent |
|
5 years |
Rs 12.5 L |
Rs 36.0 L |
Rs 37.2 L |
Rs 85.7 L |
Rs 39.3 L, 31 percent |
|
6 years |
Rs 12.5 L |
Rs 43.2 L |
Rs 44.6 L |
Rs 100.3 L |
Rs 24.7 L, 20 percent |
Assumptions used: rent at Rs 60,000 a month, a loan of 70 percent at 8.5 percent drawn progressively so roughly half is outstanding on average, and GST at 5 percent on the under construction price. Change the rent and the answer moves. At Rs 40,000 a month on a four year build you keep 51 percent. At Rs 80,000 you keep 35.
The point is not the specific number. It is that only Rs 12.5 lakh of the overlay is fixed. The other Rs 44 lakh to Rs 88 lakh is a function of how long you wait. That is the one thing the developer controls and you do not.
5 percent without input tax credit on most residential purchases, and 1 percent only if two conditions are met together. A ready unit holding its occupancy or completion certificate attracts none at all.
For GST on under construction property to fall to 1 percent, two conditions must both hold. The gross amount charged must be Rs 45 lakh or less, and the carpet area must not exceed 60 square metres, about 645 sq ft. Delhi NCR counts as a metro here. So Gurugram gets the tighter 60 square metre limit rather than the 90 applying to non-metros.
Miss either condition and the 5 percent rate applies, even on a flat priced below Rs 45 lakh. The Rs 45 lakh test counts preferential location, parking, development and common facility charges, though it excludes stamp duty and maintenance deposits.
One timing point runs in the buyer's favour. GST is charged on each instalment as the builder raises it, so it spreads across the construction schedule rather than landing at once. An instalment paid after the completion certificate issues attracts none.
The corridor changes the discount available and the yield you earn while holding. Every rate below is an asking price on super built up area from portal data, not a registered transaction value.
|
Corridor |
Asking rate, per sq ft |
Portal reported yield |
Asking movement, 12 months |
|
Golf Course Road |
Rs 19,650 to Rs 39,650, average Rs 27,350 |
2 to 3.6 percent |
Below the 2024 peak |
|
Golf Course Extension |
about Rs 18,887 |
3 to 4.7 percent |
minus 3.3 to plus 20.3 by sector |
|
Dwarka Expressway |
about Rs 14,000 |
2 to 2.5 percent |
minus 1.2 to plus 9 by sector |
|
New Gurgaon |
about Rs 10,950 on flats |
about 2 percent |
plus 4.8 on flats |
|
SPR |
Rs 12,750 to Rs 18,350 |
about 1 percent |
minus 8.6 to plus 1.2 by sector |
Note what this does to the choice. On a corridor yielding 3 to 4.7 percent, a ready unit earns while an under construction one does not, which widens the ready case. On SPR at 1 percent that argument barely exists, as SPR investment sets out. Gurgaon corridor prices also diverge sharply inside a single stretch, so the sector matters more than the label.
Ready in most cases in 2026, and under construction only where the build is short and the discount is real. Four situations sort it.
Buying to occupy within a year? Ready, and the arithmetic above is why. Buying on a corridor with the yield to earn while you hold? Ready again. Golf Course Extension Road at 3 to 4.7 percent pays you during the years an under construction buyer pays rent.
Buying under construction with a filed possession date under three years and a discount above 25 percent? That case works, provided you can carry rent and instalments together. Buying under construction on a five year plus horizon? The discount is largely notional. If this is not you, stop here.
You can claim interest at 10.80 percent a year on everything paid, for every month of delay. That is a statutory remedy rather than a negotiation.
Rule 15 of the HRERA Rules, 2017 sets the rate. It is the State Bank of India highest marginal cost of lending rate plus two percent. SBI's highest tenor rate is 8.80 percent effective 15 August 2026, giving exactly 10.80. Because MCLR moves, check the current tenor rate before you rely on it.
Section 18 of the Real Estate (Regulation and Development) Act, 2016 gives you two routes. Continue in the project and be paid interest for every month of delay, or withdraw and recover the amount paid towards that unit with interest. On a Rs 2 Cr exposure and a two year delay, the interest entitlement is Rs 43.2 lakh.
Run your model at a two year slip rather than the filed date. A possession delay Gurgaon buyers face routinely turns a four year build into six. On the table above that cuts your kept saving from 43 to 20 percent. Our possession delays in Gurgaon read covers the full remedy.
On the date you acquired the right, not the date you took possession. That distinction decides whether a sale is long term or short term.
Long term treatment on immovable property requires a holding period beyond 24 months. For an under construction purchase the acquisition date is generally the allotment or agreement date, not the handover. A buyer who allotted four years before possession may already be long term on the day they get keys. Confirm the position for your specific documents with a chartered accountant, since the paperwork decides it.
Long term gains are taxed at 12.5 percent without indexation for transfers after 23 July 2024. One exclusion catches non residents. The option to pay 20 percent with indexation on pre July 2024 acquisitions is open to residents and HUFs only.
Six things, and the first two are where buyers get sent to the wrong place.
Verify the HARERA registration and the filed completion date at haryanarera.gov.in or hareraggm.gov.in. Guidance pointing you to hrera.in or hrera.org.in is not sending you to a government domain. That error is common enough to be worth stating plainly.
Second, read the quarterly progress reports filed on the authority's portal, and the chartered accountant certified withdrawal certificates. That is how you check project funds are being applied to that project. You cannot inspect an escrow balance directly, and anyone telling you to is describing something that does not exist for a buyer.
Then confirm whether your quoted rate is carpet or super built up. Then read the grace period and force majeure wording in the agreement. Then model the payment schedule at a two year slip. Then check the developer's delivered record on completed projects rather than launched ones.
Anyone paying rent and instalments from the same income. That combination is what turns a three year wait into a financial problem rather than an inconvenience.
NRI buyers who cannot supervise a site or press a developer in person. Anyone on a corridor where the discount is under 20 percent, since the overlay will eat all of it. Anyone whose plan depends on the filed possession date holding. And anyone buying on SPR, where the corridor yields 1 percent and three of four sectors printed negative. There is no rental offset and no momentum to wait for.
It raised the duty floor for some buyers and left about half the district untouched. This applies to both options equally, so it does not swing the choice, but it changes your budget.
The revised collector rates took effect on 1 April 2026. Per the Deputy Commissioner's statement, the average increase was 15 to 30 percent across residential, agricultural and commercial categories. About 51 percent of the district saw no change at all, and around 11 percent of areas rose by as much as 75 percent.
Duty is charged on the higher of your transaction value or the collector rate. A discount on an under construction unit does not always reduce your duty.
Time is the first Risk on under construction, and it is the one that compounds. Every additional year adds roughly Rs 14.6 lakh of overlay on the example above, against a discount that is fixed at purchase.
Delivery quality is second, since you are buying from a rendering and a specification sheet. Third, developer credit, because instalments paid into a stalled project are capital you cannot access or let.
On ready stock the risks invert. You pay the full price at once, you inherit the building's condition and its maintenance history, and you have no ability to negotiate specification. And on both sides, corridor risk applies equally: sector prints inside a single corridor run from minus 8.6 to plus 20.3.
Price based: measure against registered comparables in your own project, not a corridor average. Then net out duty already paid, exit costs and capital gains.
Event based: on ready stock the trigger is a record registered print in your own tower. On under construction it is possession plus 18 to 24 months, which is roughly how long a secondary market takes to form after handover.
Time based: hold beyond 24 months from acquisition so gains are long term. On an under construction purchase that clock may already have run through the build. It is one of the few structural advantages the option carries.
Ready, unless the build is under three years and the discount is above 25 percent. That is a narrower window than the market implies.
The honest answer on ready to move vs under construction is that the discount is real and most of it is spent waiting. At three years you keep 55 percent of it, at six years 20. The build period decides the outcome and the developer controls it. So price the slipped case rather than the filed one, and treat the filed date as a claim.
Choosing between the two on Rs 1 Cr to Rs 10 Cr, with a decision due in 60 to 90 days? Send both options with their sectors and filed dates. We return this model run on your actual numbers, plus the HARERA registration and filed completion date for the under construction option. The same schedule modelled at a two year slip comes with it.
Strata Capital Holdings tracks price band shifts, infrastructure timelines and inventory movement across Gurugram's corridors. ZYN33 brings that into every allocation conversation.
Deputy Commissioner Gurugram, public statement on the 2026-27 collector rates: effective 1 April 2026, average increase 15 to 30 percent, about 51 percent of the district unchanged, around 11 percent rising up to 75 percent
All overlay, saving and interest figures are ZYN33 calculations on the inputs stated in the body
Disclaimer
This article is general information about tax and property mechanics in India. It is not tax advice, investment advice or a recommendation to buy a specific property, and it does not account for your personal circumstances. Rates, thresholds and deadlines change. Verify every figure against the source listed above and take your liquidation plan to a qualified chartered accountant before you sell anything. ZYN33 distributes residential projects in Gurugram and is paid a transaction fee when a purchase completes. We do not act as your tax adviser or your adviser on the equity side.
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