So we have heard about the various CPF retirement sums, i.e. Basic (BRS), Full (FRS) and Enhanced (ERS), which gets committed upon reaching age 55, and for which these will generate lifetime of payout from age 65 onwards (or deferred till age 70 if so decided).

Here's an interesting response that a friend of mine obtained from CPF Board on his queries. It provided details on how the FRS and ERS will actually be formed.

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[edited extract]

Question 1: Instead of FRS or ERS, can I choose any amount that is in between, even though I have enough for ERS at age 55?

Allow us to share with you how Retirement Account (RA) will be created for you when you turn 55.

By default, the Board will create your RA when you turn 55, by setting aside the applicable Full Retirement Sum (FRS) in the RA.

The transfers of CPF accounts to make up the FRS will

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