Is the minimum deposit for Citibank maxi gain account to open the account 10k,15k,70k? What's the daily deposit balance in order to earn the base & bonus interest?

The required daily minimum to earn the base interest is $10k. You can open the account with zero dollars but for that month will not earn any interest as as long any of the day the daily balance is under 10k, it will not be eligible for the base rate.

There is no min req for bonus interets. Bonus interest is earned when you have a positive counter. A counter is stepped up (+1) when your current month lowest balance is equal or higher than the preceding month's lowest balance. A maximum of +12 can be achieved to receive up to 1.2% rate. The bonus interest is earned on the preceding month's lowest balance.

There is no best time, open the account whenever u can. Any branch most convenient to you will do.

Yes u can just park 100k there. Just dont withdraw, depositing is always fine. Withdrawing will cause the counter to reset.

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