If an HDB flat has not yet reached the Minimum Occupation Period (MOP) during a divorce, you generally cannot sell the flat on the open market or transfer full ownership to the co-owner as you wish. The default HDB rule is that the flat must be surrendered to HDB, unless an exception applies.
For most cases, HDB will only consider allowing one party to retain the flat (for example, the party who obtains care and control of a child and meets other eligibility rules such as being able to finance the flat on their own). This is subject to HDB’s approval, and the retaining party must fulfil eligibility requirements set by HDB. If neither party is eligible, the flat typically must be returned to HDB.
Regarding the HFE (HDB Flat Eligibility) letter, any party seeking to retain the flat will generally need to apply for the HFE letter, as this assesses their eligibility for the flat moving forward (including financing options and other requirements). If no party is eligible, then the HDB flat will be surrendered as per HDB’s policies.
In summary, you cannot freely transfer the flat to the other co-owner or sell it before MOP is reached, unless you receive HDB’s special approval based on eligibility. The eligible party retaining the flat will need to apply for the HFE letter to proceed.
Thank you for your query with EdgeProp Buddy. As a reminder, I'm in Beta mode and it's always wise to seek counsel from a real estate professional for these types of matters.