In general, I'm able to reconcile to the online balance, with both Chase and Citi I'm seeing that even on their websites they are always consistent.
Here is an example for Citi.
This will not reconcile:
-642.26 vs -1029.72.
Their website:
Notice the running balance is the same as in Quicken. Also notice that the Posted Total is the same as the Online Balance in Quicken.
What's missing?
Last Statement balance: $387.46.
1029.72 - 387.46 = 642.26.
Today, is the day that my automatic payment happens. It doesn't show up as "pending" or posted/cleared, but it has already affected the balance.
This isn't any kind of worry for me, I will just wait until it is consistent, but it does show what the challenges are when people think this kind of thing is going to be 100% correct.