You can only sell your existing flat after meeting its 5-year Minimum Occupation Period (MOP), counted from when you collected its keys (TOP date for an EC). If you have not hit MOP yet, you cannot sell on the open market — so the whole plan waits until you do.

Rightsizers, check this before anything else. If your current flat is recent, confirm the MOP date on the HDB Flat Portal before committing to a BTO timeline.

A BTO is a subsidised flat. If your previous flat was also subsidised (a BTO/SBF/DBSS/EC, or a resale flat bought with a CPF housing grant), you are a second-timer and owe a resale levy — a fixed sum based on your previous flat type:

2-room $15,000 · 3-room $30,000 · 4-room $40,000 · 5-room $45,000 · Executive $50,000 · EC $55,000. Halved if you used the Singles Grant.

It is cash or from sale proceeds (not from a housing loan), paid at BTO key collection. Enter it in the sale-proceeds section so your net cash is accurate. No levy if your previous flat was bought resale without any grant.

When you collect your BTO keys, HDB requires you to dispose of your existing flat within 6 months. You cannot keep two HDB flats.

Note on ABSD: A BTO is an HDB flat bought as your home, and you must sell your existing flat to take it — so there is normally no ABSD on a BTO purchase. ABSD (and the 6-month ABSD remission claim) only applies when you buy a private/condo 2nd property while keeping your first — that is a different scenario and a different tool.

For this BTO plan, the deadline that matters is the 6-month HDB disposal rule, counted from key collection. The milestone that satisfies it is the buyer exercising the OTP within that window — the exercised OTP legally binds the sale. Ideal setup: grant the OTP by Month 5 · buyer exercises by Month 6. Completion then follows in the normal resale timeline (~3 months after exercise) — keep HDB informed as it progresses.

You cannot own two HDB flats simultaneously for an extended period. Once you collect your BTO keys, HDB requires you to commit the sale of your existing flat within 6 months — satisfied by the buyer's exercised OTP; completion then follows in the normal resale timeline.

1. Booking (ballot success → flat selection) — pay booking fee.
2. AFL signing (~a few months later) — pay 10% less booking fee + stamp duty. This is an early money milestone only.
3. Construction — you pay nothing.
4. Key collection — HDB notifies you the flat is ready and gives your key collection appointment date. Pay the balance, collect keys, move in.

Which date to watch: for selling your existing flat, it is the key collection date — the 6-month disposal clock starts there, not at AFL. HDB gives an estimated completion early on, then a firm key collection date as the project finishes.

Step 1 — Booking fee: $500 (2-room Flexi / Community Care Apartment) · $1,000 (3-room) · $2,000 (4-room & larger, incl. 5-room / 3Gen) — paid at booking
Step 2 — At signing Agreement for Lease (AFL): 10% of flat price minus booking fee already paid. Can use CPF OA. BSD payable within 14 days of AFL signing.
Step 3 — During construction: you pay nothing. The progressive schedule is HDB's internal draw on the contractor — not your cash. (An HDB loan charges no interest during construction; a bank loan is disbursed as a lump sum at key collection.)
Step 4 — At key collection: remaining balance = flat price − 10% downpayment − loan amount. Legal fees payable at keys.

When you sell your HDB, all CPF principal + accrued interest at 2.5%/yr must be returned to your CPF OA. This is not a cost — it goes back into your OA and is fully reusable for your BTO or next property purchase. Check exact amount at cpf.gov.sg → My Statement → Housing.

OTP granted → exercise deadline: 21 days
OTP exercised → resale app submission: as stated in OTP Page 4 (typically 14–30 days)
HDB submission → acceptance: ~28 working days
HDB acceptance → completion: 8 weeks (HDB sets the date)
Completion → cash to your bank: ~5 working days
Completion → CPF refund to OA: 2–4 weeks
Total OTP → completion: typically 3–4 months

The resale application is submitted after the buyer exercises the OTP. For an HDB resale there is no S&P agreement — the exercised OTP is the binding contract.

Seller uploads: exercised OTP, NRIC, and marriage certificate (if applicable). The exact list appears in the HDB Resale Portal at submission. Both seller and buyer submit their own portions, within 7 calendar days of each other.

The official Temporary Extension of Stay (up to 3 months after completion) is only granted if you have committed to a completed property ready for occupation — proven with an exercised OTP or signed S&P.

Important for BTO: a BTO still under construction does NOT qualify, even though you already have an address. Only once your BTO has reached key collection (completed) can you use it as your committed onward home to obtain the extension.

So: BTO keys ready/collected → ✅ extension available · BTO still being built → ❌ not eligible, arrange interim housing instead. The buyer must also consent and a $20 admin fee applies.