Bought a resale hdb, haven’t move into the house as the seller request for extension. In any event if we break up, am I possible to change my partner name to my mum that is long term pass holder?

Yes you can, but with a loss of any grants.

Also, if you are not eligible to buy a HDB on your own (due to age and single status), you may be force to give up the HDB (with subsequent financial losses).

https://www.hdb.gov.sg/cs/infoweb/residential/l...

You need to inform HDB and check with them on the eligibility under Non-Citizen Family Scheme.

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