On Friday, HDB confirmed it is reviewing the HDB conversion scheme — the rule that lets an eligible family buy the flat next door and knock the two into one. The trigger was a listing: a combined flat at Block 93B Telok Blangah Street 31, asking $2.18 million. (Note: Subsequently repriced to S$1,999,999, according to October media reports)

I have read a lot of commentary on that number over the weekend, and almost none of it did the one thing that settles the argument. So I pulled every converted-flat resale in the public registry — 415 of them since 2017, and 1,348 going back to 2000 — and priced the whole category.

Here is the short version. In the entire recorded history of this scheme, no converted flat has ever sold for $2.18 million. The highest price ever paid is $1,530,000. The ask is 42% above it. And per square foot, the ask lands eleven dollars short of the highest price per square foot ever paid for any HDB flat in Singapore — a record set at the Pinnacle @ Duxton, not in Telok Blangah.

The $2.18 million listing that put the HDB conversion scheme under review

The facts of the story are straightforward and were reported consistently by four outlets on 25 September 2026, all tracing back to a Straits Times report.

A combined flat at Block 93B Telok Blangah Street 31 was listed at $2.18 million. It is two flats that were bought separately — the first in December 2017, the adjoining unit in August 2021 — and then merged bunder the conversion scheme. Reports put it at about 1,465 sq ft with roughly 91 years of lease left. An intent to sell had been lodged. No resale application had been submitted.

HDB’s response, as carried by the Straits Times, was unusually direct for a listing it has no formal role in. It said individual three-room flats in the area had transacted at roughly $673,000 to $771,000 over the preceding six months, so two such flats at the top of that range would come to about $1.54 million. The listed price, it said, is “more than $600,000 or over 40 per cent above this amount”. It added that a transaction at that price
“will likely entail a substantial cash-over-valuation, which must be paid fully in cash upfront”, and urged buyers to do “thorough research, evaluate their housing options carefully, and plan their finances prudently so they do not end up over-paying”.

And then the line that matters most: HDB is reviewing the conversion scheme.

I am not naming the marketing agent. One outlet named an individual; three did not. That is a thin basis for putting a colleague’s name in print, and the name is not relevant to whether the price is defensible.

What the HDB conversion scheme actually is, and why I am quoting a newspaper instead of HDB

Here is something I did not expect when I sat down to write this, and it is worth telling you plainly because every other page you will read on this topic hides it.

I could not retrieve HDB’s own page on the HDB conversion scheme. The URL that Google indexes for it — the “Conversion of Adjoining Flats Scheme” page sitting under the resale planning-considerations section — returns a 404. So does the older legacy path that normally still renders when HDB’s modern pages do not. So do both
of the “Enquiry on Combination of Flats” PDF forms that show up in search results. HDB’s live planning-considerations page, which is the indexed parent of the conversion page, contains no link and no sentence with the word “conversion” or “adjoining” anywhere on it.

I do not know why. It could be HDB taking the page down while the review runs. It could be an ordinary anti-bot 404 that a human browser would not see. I am not going to assert either. But it means that the rules below are reported rules, not quoted rules, and I would rather say so than dress up a newspaper paraphrase as an HDB quote.

The only substantive text I could pull from an HDB-hosted file is a section heading in HDB’s own Estate Agent Toolkit manual: “Submitting an application to buy Two Adjoining Flats under the Conversion Scheme”. That confirms the application exists and goes through the e-Resale system. It states no criteria at all.

What follows is the Straits Times’ 25 September 2026 explainer, and it broadly matches what has been reported for years. Treat it as reported, and check it with HDB before you act on it.

The arithmetic that proves it is two three-room flats

Start with the one thing I can verify independently, and it is a satisfying check.

I pulled every transaction ever recorded at Block 93B Telok Blangah Street 31. There are 75 of them. Every single one is the same flat model — Model A — with a lease commencing in 2018, and the block contains exactly two flat sizes: three-room at 68 sqm and four-room at 93 sqm. Nothing else.

So if the listing is two combined three-room flats, the floor area has to be 68 + 68 = 136 sqm. Convert that: 136 × 10.7639 = 1,463.89 sq ft.

The reported listing size is 1,465 sq ft. My arithmetic is 1.11 sq ft away from it.

That is as close as two independent routes to a number ever get, and it confirms the composition without needing anyone’s word for it: two 68 sqm three-room flats, in a 2018-lease block, combined. It also explains the “about 91 years” of remaining lease, which is what a 2018 lease has left in 2026.

There is a second confirmation sitting in the registry. Across the 415 converted-flat sales, 136 sqm is the second most common floor area in the entire dataset, appearing 44 times — and every one of those 44 is classified as a five-room flat. Two three-room flats knocked together is not an exotic outcome. It is one of the standard shapes this scheme produces.

All 415 converted-flat resales recorded from January 2017 to September 2026. Sizes run from 92 sqm to 193 sqm across 54 distinct floor areas.

415 converted flats, priced: the table nobody has published

Every page currently ranking for this topic gives you rules and maybe one asking price. None of them gives you the market. So here it is.

The registry marks a combined flat with the flat model “Adjoined flat”. That label produces 415 resales from January 2017 to September 2026, 50 in the 2015–16 archive, 84 in 2012–14 and 799 in the 2000–2012 archive — 1,348 transactions since 2000. It appears nowhere at all in the 1990–1999 table, which is consistent with a scheme reported to have started in 1993 and taken years to produce resales.

How the market has moved, by year of sale:

Median price up 32.2% and median psf up 35.2% since 2017. Note the 2019–20 dip, which matches the wider HDB market of those years rather than anything specific to converted flats.Two things jump out of that table. The first is that roughly four converted flats change hands a month across the whole island — between 31 and 50 a year, every year, with no trend in volume. This is a genuinely tiny market, and tiny markets price badly, in both directions.

The second is that the whole category sits around $900,000, not around $2 million. The median converted flat sold in 2026 went for $915,000 at $597 psf. The median size across the dataset is 139 sqm, or 1,496 sq ft.

One structural point worth knowing before you read any “jumbo flat” statistic anywhere: the registry classifies these flats by flat type as well as model, and the split is 237 five-room, 141 Executive and 37 four-room. A converted flat does not resell as a “jumbo”. It resells as whatever type HDB assigns it — which is why the category is so hard to find in the published statistics, and why it quietly contaminates other people’s numbers.
I come back to that.

What a converted flat has never sold for

Now the test that the weekend’s commentary needed.

Of 415 converted-flat sales since 2017, the number that transacted at or above $2,180,000 is zero. Not “few”. Zero. Here is the top of the market, and it is a short list:

So the full distribution looks like this: 42 converted flats have ever crossed $1 million. 13 have crossed $1.2 million. One has crossed $1.5 million. None has come within $650,000 of the Telok Blangah ask.

The record holder, Block 50 Moh Guan Terrace, is worth pausing on, because it is the single strongest comparable the seller could possibly reach for — and it does not help them. It is in Tiong Bahru. It is a pre-war Singapore Improvement Trust block with a lease that commenced in 1973 for a building put up decades earlier, which is a quirk
I have written about before. It is 150 sqm, it is in one of the most sought-after low-rise conservation pockets in Singapore, and it took $1,530,000.

The Telok Blangah flat is asking 42.5% more than that, in a 2018 HDB block, for 14 sqm less space.

Per square foot, the ask is eleven dollars off the all-time HDB record

Price alone can mislead when sizes differ, so do it per square foot. This is where the ask stops looking ambitious and starts looking like a different asset class.

$2,180,000 over 1,463.89 sq ft is $1,489.18 psf.

The highest price per square foot ever paid for a converted flat is $947.61 — that same Moh Guan Terrace sale. The ask is 57.2% above it.

But the more useful comparison is against the whole of HDB. In an earlier piece I established that the highest psf ever recorded on an HDB flat is about $1,500, set at Block 1C Cantonment Road — the Pinnacle @ Duxton — in March 2025. I recomputed it from the raw row for this article and got $1,500.29, which reproduces that figure to the cent.

So:

The ask is $11.10 per square foot below the most expensive square foot in the history of Singapore public housing. That record was set at the Pinnacle @ Duxton: a landmark 50-storey development with skybridges, on the edge of the CBD, in the Central Area.

Telok Blangah Street 31 is a good address. It is not that. And the flat being asked to match it is not a designer sky-unit — it is two 68 sqm three-room flats with the wall between them opened up.

I tested HDB’s comparables at the block, and HDB was being kind

This is the part I was most curious about, because it is easy to nod along with a regulator’s numbers and never check them. HDB said comparable three-room flats in the area went for $673,000 to $771,000 over six months. I have the block’s entire transaction history, so let me test it at the block itself rather than “the area”.

Block 93B has recorded 15 three-room sales in total. Their range is $635,000 to $800,000, with a median of $705,000. The three most recent, all within the last twelve months, were $740,000, $758,000 and $695,000.

So HDB’s band is a touch narrower than the block’s own history at both ends. The generous reading of the comparables is not $771,000 — it is $800,000, achieved in March 2025.

Now run the seller’s best case. Two flats at the block’s all-time high of $800,000 each is $1,600,000. The ask is still 36.3% above that.

I like this result, because it cuts both ways honestly. HDB slightly understated what a three-room flat in that block can fetch. And it did not matter at all. Give the seller the most favourable comparable that exists in the block’s entire history, double it, and the ask is still more than a third above.

Worth adding the wider street for context. Telok Blangah Street 31 has recorded 559 transactions across two generations of blocks — the 80A/80B/80C stack with 2013 leases, and the 93-series with 2018 leases. Of those, 181 are three-room and 378 are four-room; there has never been a five-room sale on the street. The highest price ever
paid on the entire street, for anything, is $1,150,000, for a 95 sqm four-room at Block 80A in November 2023. The ask is 89.6% above the street record.

If a deal does happen anywhere near the asking price, the gap between price and valuation comes out of the buyer’s pocket in cash. That is what HDB was warning about, and if you want to understand how that mechanism works before you get anywhere near it, I have written up how HDB valuation and cash-over-valuation actually work.

Where converted flats actually trade, and the Woodlands puzzle

If you are hunting for one of these, the geography is not where the guides tell you to look.

Towns with eight or more converted-flat sales since 2017. Eight further towns recorded between one and ten sales; Punggol, Sengkang, Sembawang and Pasir Ris are effectively absent, which makes sense — the scheme works on old three-room stock, and those towns have almost none.Ang Mo Kio is the capital of the converted flat, with 91 of 415 sales, or 21.9% of the entire national market. That is nearly two and a half times the next town. Ang Mo Kio has the oldest three-room stock in Singapore outside the central towns, and it shows.

Now the puzzle, and I want to be careful here rather than score a cheap point. Woodlands accounts for 8 of 415 sales — 1.9%. All eight are in the same pocket of Marsiling. Yet Woodlands is routinely described, including on my own site, as holding the largest cluster of jumbo flats in Singapore.

Both things can be true, and I think they are. The Woodlands cluster is HDB-built jumbo flats from around 1989 — designed as one flat, sold as one flat. The “Adjoined flat” label I have been counting captures connverted flats: 381 of the 415, or 91.8%, have leases commencing before 1985, and 23 of them commence in the 1960s. This is old stock that got merged, not new stock that was built big.

The other reason Woodlands matters is the bottom of the table. At $293 psf, Woodlands converted flats are the cheapest big space in Singapore public housing by a wide margin — a 160 sqm median at a $514,000 median price. If floor area per dollar is your only objective, that is the answer, and it has been sitting in plain sight.

Two of the four most expensive four-room flats ever are jumbos

This is the finding I did not go looking for, and it changes how you should read any four-room statistic you see this year.

I pulled the twelve highest four-room resale prices ever recorded, out of 102,579 four-room transactions since 2017. Nine of the twelve are Blocks 1A to 1E Cantonment Road — the Pinnacle @ Duxton, Type S1. One is Boon Tiong Road. And two are the same converted jumbo at Block 50 Moh Guan Terrace: the 150 sqm unit at $1,530,000 and a 176 sqm unit at $1,500,000.

A 176 sqm flat is 1,894 sq ft. It is recorded as a four-room flat. It sits second and fourth on the four-room record board.

Which means that when a portal, a dashboard or an agent tells you “the most expensive four-room flat ever sold”, there is a real chance they are quoting you a 1,894 sq ft jumbo and comparing it to your 93 sqm flat. There are 37 four-room-coded converted flats in the current registry alone, running up to 176 sqm. The label is doing no work at the top of the distribution.

The honest version of the four-room record board:

If you want the clean version of the million-dollar story without the jumbos folded in, I keep that separately in my running count of million-dollar HDB flats, and the town that holds the national record across all flat types is covered in the Bukit Merah write-up.

A correction to my own live page

Pulling that record board caught an error on my own site, so I am fixing it here in public rather than quietly.

My live jumbo flats page says of the Moh Guan Terrace sale: “$1.53 million — Block 50 Moh Guan Terrace, Tiong Bahru (May 2026), the national 4-room record”.

That is wrong. The national four-room record is $1,550,000, set at Block 1C Cantonment Road, also in May 2026. The Moh Guan Terrace jumbo at $1,530,000 is the second-highest four-room price ever recorded — $20,000 short. Both rows are sitting in the same sorted query, and I had the wrong one.

It is a $20,000 error on a superlative, not a $20,000 error on a valuation, and it does not change the argument that page was making. But “national record” is exactly the kind of claim readers repeat, and it should be right. The page is being corrected. This is the fifth time this year I have had to publicly correct one of my own figures, and I would rather run that count in the open than pretend the number of corrections is zero.

The related claim on that page — that Woodlands holds the biggest cluster — I am not correcting, because as set out above it is about the stock of built jumbos, which is a different measurement from the 415 resales I counted here. I have added the transaction figure alongside it instead.

Who the conversion scheme actually suits

Strip out the headline and there is a genuinely good product here for a narrow group of people. The scheme has been quietly producing about four resales a month for a quarter of a century because it solves a real problem.

If you are doing the money side of this, the stamp duty and affordability maths on two sequential purchases is genuinely awkward, and the sequencing matters more than most people expect. You can run your own numbers with the free calculators at listings.sg/tools before you speak to anyone.

The verdict

All of the transaction figures in this article were computed from the HDB resale registry published on data.gov.sg, read on 26 September 2026. If you want to see the market for your own flat type rather than this one, the video library is at buyers.sg, and a free valuation is at buycondo.sg.

Frequently asked questions