Why can't I withdraw my CPF before 55 if I have the Full Retirement Sum?

The CPF system is designed to help all Singaporeans save for retirement. The more you set aside in your CPF for retirement, the higher your monthly CPF payout which you can enjoy starting from your Payout Eligibility Age.

As your personal circumstances, including the means to support yourself financially in retirement besides your CPF savings, could change, it would not be prudent to make significant lump sum CPF withdrawals too far in advance of your retirement. 

Meanwhile, you can choose to tap on your CPF savings to meet expenditure needs such as housing.