What Is a Dual-Key Condo in Singapore?

One title deed, two front doors. Here's how dual-key units work, who they're for, and whether the numbers actually make sense.

Answer: A dual-key condo is a single unit with two self-contained living spaces typically a main 23 bed unit plus a studio sharing one title deed. You pay stamp duty on one property, but can rent out the studio for $1,500$2,500/month while living in the main unit. Popular with multi-gen families and investors chasing higher rental yield (3.54.5% vs 2.53.5% for regular units). The trade-off: smaller resale buyer pool and two compact spaces instead of one spacious home.

Typical Dual-Key Layout

What you get behind the shared foyer

ComponentMain UnitStudio Unit
Bedrooms231
KitchenFull kitchenKitchenette
Bathroom12 (ensuite + common)1
Living areaFull living/diningCompact living
Size (typical)650900 sqft350500 sqft
EntranceOwn door from shared foyerOwn door from shared foyer
Total size1,0001,400 sqft (one title deed)

Both sides have separate utility meters. The shared foyer is part of your strata area.

Who Buys Dual-Key Units

Multi-generational families

Parents live in the main unit, adult child (or elderly parent) lives in the studio. Close enough to help each other, separate enough for privacy. One property purchase instead of two saves a massive amount on ABSD.

Owner-occupier investors

Live in the main unit, rent out the studio. The rental income ($1,500$2,500/month) offsets your mortgage. You get investment income without buying a second property and triggering ABSD.

Pure investors

Rent out both units to maximise yield. Two rental incomes from one property means higher gross yield. Studios command higher per-sqft rent than larger units, so the blended yield beats a single large unit.

Rental Yield: Dual-Key vs Regular Unit

Based on a $1,500,000 purchase price

ScenarioMonthly RentAnnual RentGross Yield
Regular 3-bed (1,200 sqft)$3,800$45,6003.0%
Dual-key studio only$2,000$24,0001.6%
Dual-key main unit only$3,000$36,0002.4%
Dual-key both rented$5,000$60,0004.0%

Estimates based on OCR condo rental data. Actual rent depends on location, condition, and market. Gross yield = annual rent / purchase price.

Stamp Duty Same as a Regular Unit

This is the big advantage. A dual-key unit is one title deed, so you pay stamp duty on one property. Compare buying a dual-key at $1,500,000 vs buying a 2-bed ($1,000,000) + studio ($500,000) separately:

ApproachBSDABSD (SC)Total Stamp Duty
Dual-key at $1,500,000 (1st property)$44,600$0$44,600
Two units: $1,000,000 + $500,000$24,600 + $9,600$0 + $100,000$134,200
You save$89,600

ABSD on 2nd property for SC = 20%. Buying separately means the second unit triggers full ABSD. Dual-key avoids this entirely.

Resale Considerations

Dual-key units have a smaller resale buyer pool. Here's why:

  • Most home buyers want one comfortable living space, not two compact ones
  • The total sqft is split awkwardly neither side feels spacious on its own
  • Banks may value dual-key units slightly lower on a per-sqft basis
  • Fewer comparable transactions makes pricing harder
  • The layout only appeals to a specific buyer profile (multi-gen or investor)

That said: In projects where dual-key units are popular (e.g., near MRT, strong rental demand), resale can still be healthy. The key is buying in a location where rental yield is the draw, not just layout preference.

Pros vs Cons

ProsCons
One stamp duty bill, two living spacesSmaller resale buyer pool
Higher rental yield (3.54.5%)Neither unit feels spacious
Multi-gen flexibility (privacy + proximity)Higher MCST fees (larger total sqft)
Counts as one property for ABSDTwo tenants to manage if fully rented
Rental offsets mortgage (live in one, rent the other)Cant sell the studio separately

Run the numbers on a dual-key unit

Plug in the purchase price and see your stamp duty, monthly mortgage, and what rental income you need to break even.

FAQ

What exactly is a dual-key condo unit?

A dual-key unit is a single condo unit with two separate, self-contained living spaces sharing one title deed. Typically it’s a main unit (2–3 bedrooms, kitchen, living room) and a smaller studio (1 bedroom, kitchenette, bathroom) with separate entrances from a shared foyer. You buy one unit but get two lockable, liveable spaces.

Is stamp duty higher for a dual-key unit?

No. Since a dual-key unit is a single title deed, you pay BSD and ABSD on the total purchase price as one property. There’s no additional stamp duty for the second key. A $1.5M dual-key unit pays the same $44,600 BSD as a regular $1.5M condo.

Can I rent out just the studio side of a dual-key unit?

Yes, and that’s the main appeal for owner-occupiers. You live in the main unit and rent out the studio. This is not subletting — you’re renting part of your own property. Rental income from the studio can offset $1,500–$2,500/month of your mortgage.

What is the typical rental yield on a dual-key condo?

Dual-key units can achieve 3.5–4.5% gross yield when both sides are rented out, compared to 2.5–3.5% for a regular unit. The studio commands a higher per-sqft rent, boosting overall yield. However, vacancy risk doubles since you have two tenants to manage.

Are dual-key units harder to sell on resale?

Generally yes. The buyer pool is smaller because dual-key layouts don’t appeal to everyone. The total size is usually 1,000–1,400 sqft split into two small spaces rather than one comfortable home. Resale typically takes longer than a standard 3-bedroom unit of similar size.

Does a dual-key unit count as one or two properties for ABSD?

One property. Since it’s a single title deed with one strata lot, it counts as one residential property for ABSD purposes. This is the key advantage — you get two rentable spaces while only “using up” one property slot.

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Last updated Feb 2026. Rental yield and pricing are estimates based on market data. Stamp duty rates effective 27 Apr 2023. This is general information, not financial advice.