There's no general public history for a certain "HDB accrued fascination 90 27." This is likely an interior reference range or tackle. Accrued curiosity is really a critical ingredient of HDB flat possession, especially for owners who made use of their CPF Common Account (OA) to finance their house. Whenever you sell your HDB flat, you must refund the principal degree of CPF employed for the downpayment, grants, and month to month installments, along with the accrued desire, back again into your CPF account. This interest is the quantity your CPF cost savings would have acquired if they had remained in your OA, calculated for the prevailing CPF OA curiosity rate (at this time 2.five% for each annum) and compounded annually. The refund is obligatory, and It is deducted from the profits proceeds. You'll be able to check the here precise quantity of CPF made use of and accrued curiosity on the CPF Web page's "Residence Possession" dashboard by logging in along with your Singpass.