This is probably on many Singaporeans minds now on what they want to do with their CPF OA above $20,000. Let's summarise the current offerings: OCBC 8 months Fixed Deposit - 3.88% vs Singapore T-Bills 6 months- 3.85-4.00% (Depends on competitive tranche results) To be honest, there is not much to compare between them. T bills are only worth if the 6 months tranche results are 4% and above. If it is too difficult to think of a magic number, just sign up for the OCBC 8 months FD with your excess CPF OA. It's definitely better than being indecisive and leaving the money in CPF OA which is the lowest interest. When to put in the Fixed Deposit with OCBC? The answer is definitely the first week of the calendar month. This is because CPF counts the the lowest account balance clocked for that particular. So do it at the first week or two of the calendar...