Can my mother will her flat to her son and granddaughter from another son

Short answer: Yes, but only if HDB’s eligibility and ownership rules are met. Your mother can state in her will that the HDB flat (or her share) is to be given to her son and a granddaughter from another son, but the actual transfer depends on HDB’s inheritance and eligibility criteria.

Key points to check:
- Type of ownership
- Joint tenancy: If your mother co-owns under joint tenancy and she passes on, her share automatically goes to the surviving co-owner(s). A will cannot override this.
- Tenancy-in-common or sole ownership: Her share (or the whole flat if sole owner) can be distributed via her will to the named beneficiaries, subject to HDB rules.

- Beneficiary eligibility to take over the HDB
- Each beneficiary who is to become an owner must generally be at least 21 years old and a Singapore Citizen or Permanent Resident.
- At least one owner must form an acceptable family nucleus under HDB rules. If the intended owners are a son and a granddaughter, ensure they can form a valid family nucleus (for example, parent and child). If not, HDB may not allow co-ownership in that pairing.
- If a named beneficiary already owns another HDB flat or private residential property, they may be required to dispose of the other property or the inherited flat, depending on circumstances and whether the Minimum Occupation Period has been met.
- If the flat has not met its Minimum Occupation Period, HDB can require sale in the open market if beneficiaries cannot meet the requirements to retain.

- If beneficiaries cannot retain the flat
- If the intended beneficiaries do not meet HDB’s criteria (age, citizenship/PR status, family nucleus, other property ownership), HDB will typically require the flat to be sold and the sale proceeds distributed according to the will.

- Religion-specific rules
- For Muslim estates, distribution follows Muslim inheritance law. A will can only cover part of the estate, and the shares for heirs are determined under Muslim law, then still subject to HDB’s eligibility to retain.

Practical steps:
- Confirm the current ownership type of the flat.
- Review each intended beneficiary’s age, citizenship/PR status, existing property holdings, and whether they can form an acceptable HDB family nucleus together.
- If needed, consider naming a single eligible beneficiary to take ownership, with instructions in the will to distribute sale proceeds or provide monetary gifts to others, in case HDB does not allow the intended co-ownership.
- Engage a lawyer to draft the will precisely and to advise on fallback provisions if HDB retention is not allowed.
- After passing, the estate’s executor will apply to HDB for retention approval or proceed with sale if required.

If you share the flat type, ownership structure, MOP status, and the beneficiaries’ ages and citizenship/PR status, I can assess whether the son and granddaughter pairing is likely to be allowed to retain the flat or if a sale is more likely.