Keeping Your HDB and Buying a Condo: What the Numbers Say

Plenty of HDB owners dream of keeping the flat as an investment and buying a condo to live in. After your Minimum Occupation Period, it is allowed. The question is not whether you can, but whether the numbers make sense, because keeping both triggers costs that a straight upgrade avoids. This is what keeping your HDB and buying a condo actually costs, and when it is worth it.

You can, after your MOP

Once you have met your flat's five-year Minimum Occupation Period, you are generally allowed to buy private property and keep the HDB. Before the MOP, you cannot own both. So the first condition is simply that your flat has crossed the five-year mark. After that, the question becomes financial.

Keeping the HDB versus selling it when you buy a condo.

The ABSD is the big cost

The largest number is ABSD. Because the condo is your second property, a Singapore citizen pays 20 percent, which on a $1.5m condo is $300,000, upfront and in addition to normal stamp duty. Crucially, the married-couple remission does not help you here, because it requires selling your first property within six months. If the whole point is to keep the flat, you forfeit that refund. So the $300,000 is a real, permanent cost of keeping both.

The financing gets tighter

Keeping the flat also squeezes your loan:

• If you still have an outstanding home loan, the loan on the condo is capped at 45 percent of its price, with at least 25 percent paid in cash. That is a far larger cash requirement than the 75 percent loan and 5 percent cash floor a single-property buyer enjoys.
• If your HDB loan is fully paid, a higher loan limit can apply, which changes the maths considerably.
• Either way, both the flat's costs and the condo loan must still sit within your 55 percent Total Debt Servicing Ratio.

The practical effect is that keeping both demands a lot more cash and a stronger income than a straight upgrade.

What the flat earns, honestly

Against those costs sits what the flat gives you:

• Rental income, if you let it. After the MOP you may sublet the whole flat subject to HDB's rules and approval, so check what is allowed before counting on it.
• Appreciation, if the flat holds or grows in value, though an ageing flat also faces lease decay over time.

Be realistic: rent on an HDB flat is modest, it is taxed at non-owner-occupied rates, and an older flat's value is not guaranteed to rise. Count the net income after tax and costs, not the gross rent.

When keeping both makes sense

It can be the right move when:

• You have the substantial cash for the ABSD and the larger downpayment without stretching.
• Your income comfortably carries both within TDSR.
• The flat earns a worthwhile net yield, or has strong reason to appreciate.
• You genuinely want the long-term exposure to two properties.

When it does not

It usually does not work when:

• The $300,000 ABSD and the bigger cash requirement would stretch you.
• The flat's net yield is thin once tax and costs are counted.
• You would be carrying two loans uncomfortably close to your TDSR limit.
• The capital tied up in the flat would do more for you elsewhere, including in a single, better home.

In these cases, selling the flat and upgrading cleanly is usually the stronger decision.

A considered view

Keeping your HDB and buying a condo is allowed after your MOP, but it is an expensive choice that only makes sense with real financial strength and numbers that clearly justify it. The ABSD alone is a large, permanent cost, and the tighter loan raises the cash you need. If you are weighing it, I am happy to run both paths with you, keeping both versus selling and upgrading, so you can see which actually comes out ahead.