The $2.18M Jumbo HDB Flat, Decoded — and How Combining Units Legally Actually Works

Two 3-room flats that sell for about $1.54M together have been joined into one flat and listed at $2.18M. That gap is why HDB is now reviewing the jumbo-flat scheme.

The flat is at Block 93B Telok Blangah Street 31: two 3-room units combined into a 1,465 sq ft corner flat with about 91 years of lease left (ST via Yahoo). No resale application has been filed yet, so $2.18M is an asking price, not a transaction.

Here’s how the numbers work, then the real rules if you’re thinking of combining units yourself.

What the two halves actually sell for

We pulled every 3-room resale in the same block cluster (Blocks 90A–93B, lease from 2018) over the past 12 months from HDB’s resale records.

That range matches the $673,000–$771,000 HDB itself quoted.

Measured per square foot, the gap is just as clear:

	Price	Size	$ psf
Jumbo flat (asking)	$2,180,000	1,465 sq ft	~$1,488
One 3-room (top sale)	$771,000	~732 sq ft	~$1,053
One 3-room (median sale)	$739,444	~732 sq ft	~$1,010

To be fair to the seller, a jumbo flat is rare. News reports put the count at roughly 2,900 out of about 1.1 million HDB flats (ST via Yahoo). Rarity is worth something. The question is how much, and who pays for it.

The gap is paid in cash

Your bank loan or HDB loan and your CPF only go up to the flat’s valuation. Anything above that is cash over valuation (COV), paid in cash.

That $638,000 is our estimate, not an official valuation. The actual valuation could land higher. But a buyer should go in expecting a large cash top-up, not hoping for one.

Can you combine two HDB flats yourself?

Yes, under HDB’s Conversion Scheme, which has run since 1993. The rules are narrow:

• 3-room or smaller only. The two flats must be next to each other. You can’t combine two 4-rooms or two 5-rooms.
• Families only. Singles can apply only when buying with their parents. If you already own one flat and buy your neighbour’s, the ethnic (EIP) and PR quotas don’t apply to that purchase. They only apply if you’re buying both flats and own neither yet (Dollars and Sense).
• HDB checks the pair first. You submit an enquiry form and HDB tells you whether the two flats can be combined before you buy.
• Clear your existing loan. If you already own one of the flats, its housing loan must be fully paid off before you take a loan for the neighbour’s flat.
• The works: you need at least one opening of 1m × 2m between the flats, and one set of utility meters removed.

Neither HDB nor IRAS clearly says whether ABSD applies when the second flat is bought under this scheme, so confirm that before you commit. The whole scheme is also under review right now, so check HDB’s latest position before you plan around it.

Combining two condo units

It can be done, but it is more expensive and involves more approvals than most people expect.

Stamp duty comes first. If you’re a Singapore Citizen who owns one unit and buys the unit next door, the second unit counts as your second residential property, so ABSD is 20%. On a $1.5M unit, that’s $300,000 ABSD plus $44,600 BSD, or $344,600, before any work starts. We couldn’t find any IRAS remission for combining units, and merging them later doesn’t reverse ABSD you’ve already paid. Check your own case with IRAS.

After that, you’re looking at a chain of approvals:

1. URA planning permission to combine the two strata lots into one (SLA). If the works add floor area, the MCST needs a 90% resolution (URA).
2. MCST approval for anything that touches common property or the facade.
3. Structural sign-off. Walls between condo units are often load-bearing, so expect a professional engineer’s assessment.
4. New share values, through an application to BCA ($1,500 per application, BCA).
5. A new strata title, lodged with SLA.

Your bank also has to agree before two mortgaged titles become one.

And landed?

SLA’s own example of amalgamation is two semi-detached owners combining their land to build one bungalow. It needs URA planning permission first, then the titles are merged, and the second plot attracts ABSD on the same basis as a condo.

If what you really want is to live near family

A lot of interest in jumbo flats comes from families who want more space close to each other. There are cheaper ways to get that without combining units:

• Proximity Housing Grant: $30,000 to live with your parents or child on a resale flat, or $20,000 to live near them.
• Family Care Scheme: priority for parents and children applying for BTO flats close to each other, plus joint balloting for two units in the same project, which replaced the old Multi-Generation Priority Scheme.
• 3Gen flats: a BTO or resale option when parents and a married couple buy together.

With two separate flats, each household keeps its own title, loan and exit.

The bottom line

Jumbo flats are rare, and the space is real. But the asking price here is 41% above what its two halves sell for, and that difference would be paid in cash above the valuation.

If you’re weighing a combined flat against simply buying bigger, I’m happy to run the numbers with you.

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Sources

• AsiaOne — $2.18m Telok Blangah jumbo flat: HDB reviewing scheme
• The Straits Times via Yahoo — HDB reviewing ‘jumbo’ flat scheme
• The Straits Times via Yahoo — What is a jumbo flat and the HDB conversion scheme?
• data.gov.sg — HDB resale flat prices
• HDB — Conversion Scheme application procedure
• HDB — Enquiry on combination of flats under the Conversion Scheme
• Dollars and Sense — What are HDB jumbo flats
• IRAS — Additional Buyer’s Stamp Duty
• IRAS — Buyer’s Stamp Duty
• SLA — Issue of Titles
• URA — Strata-titled residential
• BCA — MCST / strata management
• HDB — Proximity Housing Grant (Families)
• HDB — New Family Care Scheme (Proximity)
• HDB — Couples and Families

Transaction figures are completed HDB resale records; the $2.18M is an asking price. Scheme rules are under HDB review and may change. This is general information, not financial or legal advice. Eugene Tan · CEA R074026J · PropNex.