kayjay

I have 4 Citi Thank You sponsor accounts. One each for my wife's checking accounts and one each for my Thank You and my wife's Thank you credit card. For various reasons I merged my and wife's accounts a few years ago.

The points earned on all of the above have no expiration. If I close any but not all of the sponsor accounts the previously unused points associated with that sponsor account will expire within 30 days unless used within that period.

The checking accounts go back many years, the credit cards were opened for the bonuses.

Citi "stacks" (their terminology not mine) the points in chronological order, first in first out. Their computer system is able to track your usage across multiple sponsor accounts. However, their CS representatives claim that they cannot provide an individual with such an analysis.

I cannot provide any input as to whether expiring miles will be used first (as when you cancel one of the sponsor accounts).